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Common Wiring Methods Used Concerning Wiring a Dwelling (NEC 2002)

By Warren Goodrich
Common Wiring Methods Used Concerning Wiring a Dwelling (NEC 2002)

A new word has been added in the 2002 that replaces the words “fixture or light fixture”with this new word that is seen throughout the 2002 NEC that word is “luminaire”.


Upon entering your home, and in preparation of wiring your structure you should first mark out your switches and receptacle placement that you desire and that is required to meet the minimum safety standards of the NEC.

Click the picture icon to the left for an example of marking out a house using a floor plan as an example.

This section is for marking the receptacles in living areas. Take a tape measure, with a friend, and measure from the end of a wall to 6’along the wall, from an opening [doorway] and then measure 12’from that receptacle to the next receptacle as long as that wall is unbroken by an opening [doorway]in the wall.210.52.A.1. Now continue measuring until you have reached the end of that unbroken wall. You must make sure that the last receptacle marked, is within 6’of the end of that unbroken wall, as well as no more than 12’from that next receptacle back along that same wall. As you measure, the required distances, you should mark, with an ink pen or marker, on the stud, and at eye level with an “R”, for reference along the wall placement only, not height of the receptacle or switch. This “R”marking will represent the need for a receptacle at that point. The “R”will not represent the height that you will mark later with a measuring stick. Watch out for any obstructions such as windows framed down close to the floor, or doors, or cold air ducts, or a bad place to get a wire to that position, as you mark for receptacles [you may wire crossways only {perpendicular} but not long ways {parallel} through a cold air duct]. 300.22.Exception You must not place a receptacle or switch in a cold or hot air duct. .

Click on the picture icon to the left to see an example of do’s and don’ts on cold air ducts, using a floor plan as an example

If you hit an obstruction [examples are a doorway, window installed ceiling to floor, or built in cabinet] back up to the nearest convenient position on the wall that a receptacle can be easily mounted. You must then measure 6’[from the other side of the obstruction or break in the wall the same as it was a new wall] to the next receptacle that is required, and repeat this process until you reach another door, or the end of the wall. Keep in mind that what you are doing is setting these receptacles so that you will not be beyond the maximum Code distances allowed, between the end of the wall [6’] and between each receptacle [12’], in the living areas. Living areas are as listed but not limited to, a living room, a bedroom, a dining room, the kitchen area that is not over a counter area, a den, a residential office, a play room, an enclosed sun room, etc. 210.52.A.1 Remember that a garage, a laundry, a utility room, a hallway, a closet, or a foyer are not considered living areas and are not required to be included in the 6’/ 12’rule. In these nonliving areas receptacles are installed in an “as needed bases”.

An example of a nonliving area and what may be found in that nonliving area such as a utility room can be viewed by clicking on the picture icon to the left.

The Code requires that no wall [ in a living area ], over 2; long in those living areas, can be without a receptacle. 210.52.A.1 [with the exception of behind a door or in a non-living area such as a hallway], and any wall must have a receptacle within 6’of the end of the wall [including doorways, to be considered as an end of the wall], and the distance being no more than 12’between any two receptacles along an unbroken wall. Remember that in areas such as lofts, that are also living areas, that have a long railing, half walls, etc. has the same requirements as a full sized wall. 210.52.A.2.3 These type walls may be served with a surface mounted receptacle mounted on a post or an approved floor receptacle as long as the floor receptacle is located within 18”of the wall or railing. 210.52.3 < class="c19">Any floor receptacle installed must be installed within a box approved for the purpose and listed as a floor receptacle box. 314.27.C Each receptacle will serve 6’each direction from itself. Two receptacles 12’apart will serve 6’each, towards each other, fulfilling the 12’allowance to be covered by both receptacles. Rooms such as garages, laundries, utility rooms, etc. are exempt from the 6’/12’rule. These nonliving area style rooms are considered work areas and not living areas. 210.52.A through H.

The 6’/12’rule is intended for the wiring design of receptacles along all walls within the living areas to be within 6’of any lamp, television, radio, etc. You should find that all apparatuses designed for living areas that you may buy will have a 6’cord. [designed for a light duty and low amp usage] You should also find that all small appliances designed for the cooking areas [small appliance branch circuits] that you may buy will have a 2’cord. [designed for a heavy duty higher amp usage] This 2’cord of small appliances are designed to be used over kitchen counter areas and the placement of these kitchen counter receptacle are 2’/4’rule that will be discussed when we get to the kitchen wiring designs later on in this article. Now you should be able to see the intent of the master designs in the whole picture for safety, as per the NEC minimum safety standards.


Baseboard heaters get hot and can melt down a lamp or TV type cord. The receptacles considering baseboard heater placements in relation to those receptacles must be considered so that the receptacles are placed in the areas not over the baseboard heaters. The intent of this is to limit the hazard of that baseboard heater from causing a melt down of the insulation of those lamp and TV type cords.


Next in preparation to wiring your structure, you should nail on one example of the following boxes, to set up a measuring stick for production purposes. I would nail these example boxes onto the wall at the height suggested, [“as accepted practice”, {Code mute on height of receptacles and switches} ]. A switch box 48”[in the living areas], a receptacle box 12”[in a living area], a receptacle box, or switch box, to be used over a counter 42”[in a kitchen counter area], a washer, or dryer receptacle box 36”[in a laundry area, to be installed behind an appliance]. These suggested heights are designed to be measured at the bottom of the box, from the floor to the box. All of these example boxes should be at the height that you prefer, just stay uniform with other boxes, of the same usage design. The above suggested heights can be changed to meet your desires, just stay uniform to avoid a roller coaster look on the finished product. A ¼”variation shows up on the finished product like a sore thumb, then you would get to look at that misplaced receptacle or switch for the life of the structure.

In the past, some electricians used the following as a personal rule; hammer height, chest height, eye level, etc. These are not normally accurate, and will usually show uneven boxes, throughout the structure, for the finished product. I suggest you use a certain measuring stick with a fine line marking the height of each type box used to limit the uneven box placement that can be invited with less precise measuring styles such as hammer height.

I suggest that you make a measuring stick using the above mentioned example boxes in order to set up this measuring stick for use in measuring the rest of your dwelling. Material such as a 2 X 2 board or even smaller in diameter about six feet tall should work fine as a measuring stick. Set the new measuring stick next to the first example box that you nailed on. Be sure to set the stick on the bottom plate of the wall, not the sub-floor. The sub–floor may not be level, and this sub floor may change in height, as you move through the dwelling, thus, changing the height of the boxes. The change in height can happen, without you noticing the uneven boxes, until it is too late!

An example drawing showing a measuring stick can be viewed by clicking on the picture icon to the left.

While making the stick, mark a line on the measuring stick with a fine line pen or pencil for accuracy, so that it is even with the bottom of the example box that you just nailed up. Write above that line, on your measuring stick, identifying the intended usage of that box that the line represents with an R for a receptacle, or an S for a switch, or a T for a thermostat, etc. You may desire to mark the top of the box on the stick and the stud instead of the bottom. It really is your choice which would be easiest and fastest for you while keeping accuracy in box placement. The reason for marking the top of the box on the measuring stick and onto the stud where a box is to be nailed is so that the line set that you marked is more easily seen whiled nailing on the boxes. Now proceed to mark the measuring stick with the height of the rest of the sample boxes that you nailed on previously.

You have now made a measuring stick to mark the box heights for the rest of the boxes to be installed throughout the remainder of your dwelling. You will refer to these markings after you mark the studs throughout your dwelling, reminding you as to where, and how high each box is designed to be installed, and their designed usage, later in your wiring procedures.


The kitchen is special pertaining to the maximum allowed distances between counter receptacles. They are as follows; The sink, refrigerator, oven, and cooking range will break the counter creating a new [end of counter], the same as a doorway in the living area. 210.52.C.1 through 5. To start marking your counter receptacles you should measure from the end of the counter that you are going to start measuring, and then measure along the counter to reach 24”and mark a receptacle. Then measure a distance of no more that 48”to the next receptacle, and continue marking the counter receptacles at a maximum distance between receptacles at 48”unless you reach a stove, refrigerator, oven, or sink that breaks the counter area. If you reach one of these mentioned appliances you must then start over with the 24”, on the opposite side of that appliance because the appliance made a new end of the counter. Remember to look back to make sure that your last receptacle that you marked is within 24”from the end of the counter that you just encountered. Now look for any counter space that is more than 12”long or wider, and is not part of an island or peninsular, and also mark a receptacle over this counter space. 210.52.C.1 Any counter space wider than 12”must have a receptacle serving that counter area. 210.52.C.1

Next watch for a peninsula, or island.

The peninsula or island must have a receptacle serving any and all counter space that has a short dimension {width} of 12”or greater and a long dimension {length} of 24”or greater. 210.52.C.2 and 3

An exception is present in the 2002 NEC says that where the counter top of an island or peninsula is flat and there is no back splash or dividers etc. and there is no means to mount a receptacle within 20”above the countertop of that island or peninsula such as the bottom of an overhead cabinet installed over that peninsula or island within 20”then this receptacle is still required. However the NEC then provides an exception so that you may, in order to comply with the NEC rule of receptacle placement over kitchen counter areas of main counter, island, or peninsula, you may install a receptacle below the counter area on the side of a cabinet for example to meet that counter receptacle rule in kitchens. This is only allowed if the receptacle is within 12”of that counter top and that counter top does not have an overhang 6”or larger beyond the cabinet base.


Warning, I am in horror that this exception, placing a receptacle within 12”under a counter top on the side of a cabinet or wall is still present in the NEC in any manner. I am ashamed that I am a part of an industry that provides a set of rules allowing an exception to meet those safety rules required by setting up a very dangerous condition putting our small children at risk of a life threatening and / or terrible pain and scarring from risk of burns to that small child.

I have a severe concern with the use of the above mentioned exception to 210.52.C.1 through 5 allowing a receptacle mounted below a counter space to be installed in order to meet the kitchen counter receptacle placement rule NEC 210.52. If your inspector requires you to meet that rule in order to comply with NEC 210.52.C serving kitchen counter spaces then find any method available OTHER than using that exception to the rule allowing a receptacle to be mounted within 12”below that counter on the side of a cabinet.

I enforced this 210.52 receptacle placement of counter rule allowing a receptacle to be placed within 12”of the counter area on the end of a counter area per that exception found in 210.52.C. Due to my ruling and the electrician using that exception to the rule to meet minimum safety standards set by rules of law in my state a 2 year old child spent months in the hospital burn center to the horror of that child’s parent due to severe burns when a fryer full of hot grease was pulled off the counter top by the child pulling on that cord plugged in to a receptacle installed at eye level right in front of that child’s face. This caused hot grease to pour over that childs face and body.

To me this was a horror I will never again be a part of no matter the cost to me.

Picture a kitchen counter area. Picture a receptacle placed within 12”below that counter area to meet this rule required to be met without exception even on a counter area with no cabinets above it and totally flat counter area. Picture a 5 year old or younger child even just learning to walk, pride of the parents with unlimited love for their child. Picture the level where that child’s eyes would be approaching that counter area. That receptacle with a cord plugged into that receptacle within 12”of that counter top being exactly the same height of that child’s eyes looking for a toy to play with. That cord is an open invitation for that child to play with that cord not knowing that cord is attached to a fryer with hot grease in it sitting on the counter top above that child’s head, face, and body. Picture the results if that child pulls on that cord being a perfect invitation for that child to do exactly that. I hope you never have to experience or be a part of that disaster happening to any child !!. Please think what is said above then find a different option to avoid this risk to our children. Please do not use that exception. Please do not install a receptacle below the counter top that is eye level to most children 5 years or younger.

While I have never met the parents or the child mentioned above I will always feel pain in my heart for the rest of my life. I was the inspector who allowed that hazardous condition being installed within 12”below the counter top using that exception to meet the minimum safety standards. I enforced the rule to be in compliance with NEC 210.52. All involved, unknowingly by anyone who was involved, created a risk of the pain and scarring of that child just to follow the NEC rules. All have lived with and will live with, the rest of their and that child’s lives, the pain and anguish of that child and those family members.

Please avoid using that exception to the rule to meet the minimum safety standard or counter top receptacle placement.

Please speak out for change of this rule allowing the exception to

Article 210.52.C of the NEC to be used.

Please speak as often and loud as you can to get this exception removed.

Thank you for reading this subject, it is the most horrific part of my 30 years in the electrical industry. While there are other hazards often due to unknowing electricians creating a fire hazard or shock hazard and these type hazards cause injury and death, we have no control on that lack of knowledge in our industry other than trying to promote knowledge such as by this article and our web site. Many provide methods of increasing knowledge in the electrical industry all over the world. However this accident mentioned above hit home to me and I have heard of this not being a rare accident but rather several children have been hurt terribly due to this exception to the rule of placing that receptacle at eye level to an unknowing trusting child. This exception to the rule 210.52 is in great error and in need of change.

Peninsula counter spaces 210.52.C.3

If any peninsula is shorter than 24”inches from the connecting counter’s edge to end of counter {24”from the front of the adjoining counter to the end of the peninsula}, OR if the peninsula is shorter than 12”in width from the front to rear or the counter, then a receptacle is not required to serve that peninsula.

Remember that both the unbroken width and the unbroken length of the peninsula counter space must exceed the minimum measurements before a receptacle is required

For an illustration of number of peninsula receptacles required , click on the picture to the left.

If the total length of the peninsula counter area is 24”or longer from the connecting counter’s edge, - and - if the peninsula is 12”, or wider, in width from the front to rear of the peninsula counter area and is unbroken by a stove, sink, oven etc. , then at least one receptacle is required to serve the counter area of this unbroken peninsula counter space.

Remember that both measurements [width and length ] must be unbroken counter spaces and must be more than the minimums 12”by 24”before a receptacle is required to serve that counter space of the peninsula.

Remember that any peninsula counter space can be as wide or as long as it wants to be with only one receptacle required to serve that unbroken peninsula counter space

Island counter spaces 210.52.C.2

Island counters spaces are treated the same as the peninsula counter space except that they are measured from end to end instead of from any connecting counter’s edge.

Remember that any appliance installed in the island counter creates two island spaces that are treated, separately, as two islands. These separate islands must have their own measurement which exceeds the 12”width and 24”length minimums before a receptacle is required.

For an illustration of number of island receptacles required , click on the picture to the left.

Remember that any unbroken island counter space can be as wide or as long as it wants to be with only one receptacle required to serve that unbroken island counter space

More rules of receptacle installation serving a counter space is found in Article 210.52.C.5

A receptacle must be installed above the counter space but not over 20”above the counter space. No receptacle is allowed to be installed in a face up position in or on a countertop. Receptacles that are behind an appliance or otherwise made not readily accessible can not serve the counter space as a required counter receptacle. 210.52.C.5

If your counter space is flat and there is no place to install a receptacle over the counter, a receptacle may be installed below the counter area with intent to serve a counter top requirement but only if the counter top is flat with no back splash or walls connected to the counter top, and no cabinet within 20”above the counter that a receptacle may be mounted under that cabinet and within that 20”limit above the counter. This receptacle below the counter area can only serve as the required receptacle serving the counter area, if it is installed not more than 12”below the counter top surface and only if the counter top does not extend more than 6”beyond the supporting cabinet base. If this is counter space or island counter space an no means to mount a receptacle above the counter space then the exception allows it to be omitted. 210.52.C.5 Exception b However you MAY install a receptacle below that counter space if no other means to mount the receptacle above the counter space exists.

“Special Note” Many “AHJ’s”feel that there is an inherit danger when a receptacle is mounted in the wall of a base cabinet below the counter surface. If you would plug an electric skillet, etc. on the counter area into a receptacle mounted in the wall of the base cabinet there would be a danger to small children. This danger is felt to be present even if the receptacle is mounted below the counter and within the maximum distance of 12”from the counter top. A small child can play with that skillet, or other appliance cord and pull this hot appliance, and its ingredients, down on his or her head which could cause a severe injury due to burning of their skin.

Rules of other receptacle installation 210.52.A.1 and 2

Any receptacle in the kitchen, dining, or nook, that is not over the counters shall revert back to the 6’/12’rule. 210.52.A. 1 and 2At least one laundry receptacle is required for a single family dwelling. 210.52.F At least one receptacle is required in each attached garage. 210.52.G At least one receptacle is required in each unfinished basement in a single family dwelling. 210.52.GA laundry receptacle can not serve as these required receptacles. 210.52.G Any finished areas in a basement must be treated as a living area, the same as a normal living part of a house. 210.52.A and G The finished area of a basement is a living area and must meet the 6’/12’rule. 210.52.A The finished areas of a basement that is considered as living areas do not require GFI protection of the receptacles as any unfinished basement receptacle is required to be GFI protected.

An example of a wiring design of a finished basement can be viewed by clicking on the picture icon to the left.

At least one receptacle is required in any hall with a wall containing 10’of unbroken hall length, without passing through a hallway door. Notice this is not a door entering into a bedroom or other type room but the 10’without passing through a door is a door dividing one hallway from another hallway. 210.52.H An outside receptacle is required at grade level and not higher than 6 ½’above grade both in the front and in the rear of a single family dwelling. 210.52.E A bathroom receptacle is required to be within 36”from the lavatory basin and must be installed on the wall adjacent to the basin or basin counter top. 210.52.D

Marking Switches

Switches are installed wherever they are desired, as long as the following minimums are met, as follows. At least one switch is required to be installed inside all habitable rooms at the point the of entry of each room. 210.70.A.1 A switch is required in each hallway. 210.70.A.2 Switches are required to serve stairways at the top and bottom of stairs only if with six steps or more. 210.70.A.2.C In both attached and detached garages a switch must be mounted inside at the service door controlling a luminaire both inside, 210.70.A.2.A and a switch controlling a luminaire outside serving the stoop area of that service door [vehicular doors are exempt from a switched luminaire requirement to serve the vehicular doors]. 210.70.A.2.B An exception to the stoop luminaire rule for a switch requirement is allowed to have the stoop luminaire and switch to be omitted if an automatically switched area light such as a dusk to dawn luminaire serves that stoop area. 210.70.A.2.Exception A switch is required at each attic or crawl within reach of the entrance, only if the attic or crawl is used for either storage or contains equipment, [the luminaire must be mounted near the storage area or the equipment area. ] 210.70.A.3 A switch is required at all exterior doors to control exterior luminaire serving outside that entrance door. 210.70.B A switch is required at the entrance in each unfinished basement and utility room. 210.70.A.3

As you mark the receptacles for installation throughout the dwelling, also mark the switches, including three to eight way or more switch system designs, these switch systems are designed, as you may desire as long as the above minimums are met. There is no maximum number of how many switches that can control the same luminaire. {multiple –switch system wiring methods will be explained later in this section} Be careful not to gang more than four switches in a single box combination without special consideration, as to obtaining switch covers needed on the finish product. Switch plates for more than four switches may not be available the way you might want them. You may mount two or more multiple ganged switch boxes mounted over the top of each other, if needed. {Be careful to leave enough room between the stacked boxes, for the cable entrances into those stacked boxes, as needed}. If you mount two boxes side by side, take extreme care to be exact as to the height. A ¼”off in height between the two boxes mounted within inches of each other would stand out like a sore thumb on the finished product.

I will try to explain the reasoning of some of the accepted practices. I want to state that this is only an opinion! If you put five qualified electricians together to do the same project you would have eight or more different opinions concerning different ways of doing that same project, and they could all be within the minimum Code requirements. This is why they call it the art of electricity.

The receptacle height, for the living areas could be placed at [hammer height, 12”to the bottom of the box, or even 12”to the top of the box, ETC.] There is no required height for any receptacle except as logic requires. Just be careful to make that height of your receptacle and switch boxes uniform, and accurate throughout the dwelling areas, for each use type of the receptacle. [counter, living, appliance type receptacles or switches] There is a maximum height for receptacle to serve the 6’/12’rule of 5’6”high as a maximum, any receptacle mounted above that maximum height can not be counted as serving the 6’/12’rule. 210.52 Any receptacle that is a part of a luminaire can not be counted as fulfilling the requirements of receptacle placements meeting the 6’/12’or 2’/4’rules. 210.52 [This includes any switched receptacles that are not constant on. This switched receptacle can not serve to fulfill the 6’/12’rule]

Be careful as to your accuracy while mounting receptacle or switch boxes, because ½”difference in height of two adjacent receptacles in any given room will stand out like a sore thumb and be an eye sore to you throughout the life of the dwelling. I use 12”to the bottom of the box from the sub-floor as a normal height of receptacle boxes for living area type receptacles.

There is no height requirements for switches either. I use 48”to the bottom of the box for switches. I place receptacles behind the refrigerator, and the washer at 36”to the bottom of the box. [easy to reach from over the appliance without standing on your head to unplug the receptacle yet hidden behind the appliance] This 36”seems to hide the receptacle, and it keeps them within easy reach behind these appliances. In bathrooms over vanities you should use the 42”just like over kitchen counter tops even if the receptacle is on the side where there is normally no back splash. Some houses will have what is called a side splash that is the same height as the back splash installed on the sides of a vanity. If you used the 36”height on this type vanity with a side splash, your receptacle would be half covered on the finished product. Floor receptacles are allowed by the NEC, but they take a special installation requirement, and are normally expensive to install as the Code requires. {floor receptacle or switch boxes must be designed for the purpose and UL approved for use as a floor receptacle or switch box}314.27.C

It is my understanding that the reason for the 6’/12’rule 210.52.A.1 in the living areas, and the 2’/4’rule over the kitchen counter areas 210.52.C.1 are approximately as follows; The living areas are served by equipment, normally of light duty in amperage load, and are found with a 6’cord length. The kitchen counter areas are served by equipment normally of heavy duty in amperage load, and with a 2’maximum cord length. The goal is to eliminate the use of extension cords.

At least one wall switch controlled lighting outlet [switched receptacle or luminaire] shall be installed in every habitable room, bathrooms, attached garages, detached garages only if that detached garage is with electrical power, all exterior door entrances, utility rooms, rooms or areas with equipment to be served, rooms or areas used for storage 210.70.A Switches are required at all attic and under floor areas that contain equipment to be serviced or used for storage. 210.70.A.3 These switches are to be located at the entry to these areas and the luminaire must be in the area of the equipment or stored material. 210.70.A.3

Watch your height of switches on stairway landings. I suggest that you install these switches at a midway point measuring 48”from the first step and from the landing floor height, then mount the switch box midway between these two measurements. This makes a fair comfort zone whether you are going upstairs and reach for the switch from the landing or going down the stairs and reach for the switch from the first step. Where there is more than 5 steps on a set of stairs, you must install a 3 way switch controlling a luminaire for that set of stairs, located at the top and the bottom of the stairs. 210.70.A.2.C There is an exception to the switch requirement, on a set of stairs entering a basement with no other outlet for personnel. This switch would be required at the point of entry which would be the top of the stairs. In this occasion a 3 way switch would not be required unless a bedroom, etc. is involved where you would stay in the basement living area. 210.70.A.3

Watch the height of your receptacles over the side of your bathroom vanities. I put these at 42”at the bottom of the box from the sub floor, from the bottom of the box. Reasons for concern of this height is that sometimes there is a side splash on the vanities, and you will need the 42”height to clear these side splashes, which are the same height as the back splash of that counter. If you put these receptacles at 36”high over the vanity, you will be half covered by the back splash or if present the side splash. This also runs true over kitchen counters. In the kitchen, over the counters, I put both the switches and the receptacles at 42”from the bottom of the box, measuring from the sub floor to the bottom of that box. This allows for an even placement along the counters, upon the final product.

In the garage, I put the receptacles at 42”above the bottom of the wood bottom plate of the garage wall, and the switches at 48”above the bottom of the wood bottom plate of the garage wall. There is no minimum height in residential garages, but commercial garages require 18”minimum height from the finished floor to avoid any gas fumes accumulating in the garage. 511.3.B.1 These gas fumes will lay low to the garage floor and you should consider this commercial minimum when deciding on your own home garage. This minimum is not a requirement but should make good sense even in a residential garage. The only reason you would want to push that 18”in my mind would be if you plan to remodel that garage into a living area at a later date where you would want lower placed receptacles.

Outside I put the receptacles above the grade of the yard, enough to be safe so that water is unlikely to reach the receptacle in severe flooding. The required outside receptacles may be placed above the inside floor level. This would be fine as long as you do not exceed the maximum height for outside receptacles of 6 ½’210.52.E Remember that you must install an outside receptacle both in the front of you home and in the back of your home as required in Article 210.52.E You must also install what is commonly called bubble shields on all receptacle installed in wet locations that are 15 or 20 amp rated. Any receptacle installed outdoors such as is required in Article 210.52.E in the front and rear of a dwelling is considered as wet locations. This is new in the 2002 code. Article 406.8.B.1 This rule applies to all 15 and 20 amp rated receptacle mounted outside whether a cord is plugged in unattended or not.

As you mark the devices, as you are required [6’/12’{living areas}, or 2’/ 4’{kitchen counter areas} rule], (and more , if you desire) You might consider measuring all of the rooms, with your buddy [ if you want ceiling luminaire in them] as to the width and length dimensions of these rooms, and divide these measurements by two, for one luminaire, and three for two luminaire, etc., and mark these numeric figures on the door header of that room, for future use, in order to center the luminaire at a later time, marking an arrow pointing up for the opposite wall dimension, and an arrow pointing horizontally for the distance side to side of that room. This may speed your wiring effort in future procedures, for mounting luminaire boxes, in the ceilings.

As you mark the switches on the wall, with your pen, then also mark what they are to be used for, below the “s”that you previously marked, representing a certain switch. Then if this switch is a three, or four or more way switch system, then mark the number of switches in this switch system, then subtract one from that total number of switches, and mark a little number under the corner of the “s”letting you know in the future that you designed this switch to work with that many other switches, in unison, to operate one luminaire [such as a stairway or hallways or entrances].


The switch system example, just above, tell us that we have a foyer on a single pole switch [reminding us that there are no other switches controlling that foyer luminaire] A downstairs hall, with 2 switches on a 3 way switch system [reminding us that there is another switch somewhere in the dwelling controlling that downstairs hall luminaire]

Try clicking on each of the picture icons to the left to show a wiring schematic of a three way switch that may be of some help.

Another good link to 3way switches can be found with drawings at your choice drawn by my partner Don Kerr. "3 WAY SWITCHES"

A dining room with 3 switches, on a 4 way switch system [reminding us that there is two other switches somewhere in the dwelling controlling that dining room luminaire] an example of a four way wiring schematic link with several different wiring options of a 4 way switch "4 WAY SWITCHES" and an upstairs hall with 7 switches on an eight way switch system [reminding us that there are 6 more switches somewhere in the dwelling controlling that upstairs hall luminaire]. An example of wiring a five or more way switch would be the 4 way link above and adding as many four way switches as is required between the two three way switches wired the same as the one four way switch in the schematic found at that same link above. "4 WAY SWITCHES" This will help you when you start stringing the Romex needed to operate these specialty switch systems. [There is a two way switch system, but it is only used as a specialty switch system, to protect a gas pump, etc.] A two way switch system must have both switches in the on position in order for an appliance to run, creating a security type switch system. An example of a two way switch that is not commonly used except as a form of security style switch system described above is "2 SWITCHES IN SERIES" This is why you subtract one from the total actual number of switches so that you can know how large the particular switch system is that you plan. [ A three way switch system is only two switches / A four way switch system is only three switches, etc.]



Now count the number of boxes, for each type, that you will need. Keep in consideration that you should not gang more than four switches, or two duplex receptacles in the same box, due to the lack of availability, of larger switch, and receptacle covers. You may stack multiple-gang boxes over each other, but leave space between them to provide the room needed for the cables entering the boxes. If you stack boxes, then split the 48”height in order to get these boxes stacked as evenly to the 48”mark as possible.

Now you have to decide on the type of boxes you want to use, the following are some of the pros and cons to the different type of boxes, as I have experienced using them.

Plastic versus steel, the steel box is a conductor of electricity. The plastic or fiber box is like the double insulated effect you get with the new type of electric tools we use daily. [less chance of the plastic causing a fire or shock hazard due to the conductivity of a steel box]. The steel box, some consider to be best, due to the durability of the steel construction. The steel has pre-cast threads allowing ease in inserting the screws on the finish, allowing a minimum of breakage when you miss the nail, and hit the steel, or the plastic box, with your hammer, while nailing on the boxes, versus a high probability of breakage with the fiber box, which seems to become brittle, in cold weather. The yoke screws of a device are harder to insert the screw, on the finish, when using plastic, or fiber boxes {not bad though}. The plastic box tends to be the toughest of all of these type of device boxes. As an experiment buy one of these blue plastic receptacle boxes and then try to rip, cut, burn, hit, or otherwise attempt to destroy, that plastic box without using heavy duty tools such as a blow torch. You may find this box to be quite a foe when trying to distort or tear or burn with a cigarette type lighter. The plastic box tends to be impervious to weather, moisture, and corrosion. The fiber box has the same double insulating effect as plastic, and has the same screw characteristics of the plastic, but is known to be brittle in cold weather. {You may experience breakage as you nail fiber boxes to the studs, in the winter} You must choose the type of box yourself. Each has the pros and cons. In my opinion the plastic or fiber are my favorites due to the properties of non-conductivity that they provide, as extra safety. Some say that the steel is strongest, therefore better. I feel that once you drywall, and bury the box, what is going to break it? Chances are once it is buried flush with the drywall, it will seldom, if ever be touched again.

Before you buy your boxes, consider the following; Paddle fans weighing less the 35 pounds require a special fan box approved for the purpose, or other mounting considerations. 314.27.D & 422.18.A Paddle fans weighing 35 pounds or more must be supported independent from a box.422.18.B Fan boxes come in metal, or plastic boxes. Fan boxes can be found in any type of design such as a deep nail on type box, a shallow pancake type box, and a plastic or steel box that straddles the ceiling joist. You will find the steel fan box to have the tabs that normally have the threads for the 8/32 luminaire mounting screws on a fan box will have the hole in the tabs enlarged expecting a long 8/32 screw to pass through that tab as a stabilizer and then threading into a threaded screw hole in the back of the box. When looking at the plastic fan box, you will normally find a threaded steel nut molded into the back of the plastic box. Any of these boxes mentioned above should do fine to support a paddle fan as long as that box is listed and labeled as a fan box approved for the purpose.

The normal light boxes [not for use to install a fan] can come with a bracket to between the joist spaces, or you can cut wood to the joists, and then nail the box onto the wood header that you installed between the joists. Any light box must be capable of supporting a luminaire that exceeds 6 pounds but not more than 50 pounds, and with a maximum luminaire diameter of 16”, 314.27.B I suggest the light box should have an 8/32 size screw [not receptacle style boxes with 6/32 size screws] to mount the luminaire. The receptacle type box with the 6/32 screws can be utilized only if mounted in a wall or ceiling for the installation of a porcelain keyless or a porcelain pull chain type lightweight luminaire weighing less than the 6 pounds. These porcelain type luminaire and the like weigh less, which would allow you to use the lighter duty boxes with the 6/32 screws found in receptacle style boxes. 314.27.A. Exception Take special consideration of any heavy luminaire, more than 50 pounds, requiring special mounting needs. The heavy luminaire 50 pounds or more shall be supported independently of the box, unless the box listed for use with that weight of luminaire. 314.27.B Several examples of wiring schematics for wiring paddle fans can be viewed at the following link "FAN / LIGHT COMBO WIRING"

Are you using recessed tanks for lighting, if so, they need to be installed on the rough-in before drywall is installed, normally. Watch to get the proper recessed luminaire designed for the purpose you are using it. Are you going to have a direct contact with the insulation, or are you using insulation chimneys instead, and accept the heat loss? Direct buried recessed luminaire in direct contact with the insulation must be approved for direct contact with insulation or other combustible material, type “CT”recess tanks. Refer to the manufacturer’s recommendations printed inside the recessed luminaire. These no clearance approved for direct buried in insulation recessed luminaire usually have a recessed tank inside a recessed tank. Double insulation affect with an air space between the two luminaire tanks.

How many bathroom exhaust fans are you going to need? If you have a bathroom window that opens, then a fan is not required. If no window is present that opens, an exhaust fan will be required in that bathroom. This is a rule found in the CABO Building Code. If you are mounting the fan over a tub, or shower, you must have a fan approved for the purpose, and it must be protected by a GFCI control. 410.4.A and manufacturer’s recommendation, product’s listing and labeling. Several example wiring schematics of installing a bathroom fan is "FAN / LIGHT COMBO WIRING"

Are you going to use closet lighting? If so, remember that you must meet the following clearances.

An incandescent luminaire must be with a cover, or lens, and must meet the clearance measurements of two points as follows; 24”from the back and side walls, and 12”from any shelving [regardless of whether the shelving is there or not]. You must clear the total luminaire including the bulb, globe, and luminaire itself. 410.8.A & 410.8.D.1

A florescent luminaire must meet the clearance measurements of two points as follows; 18”from the back, and side walls, and 6”from the shelving [regardless of whether the shelving is present or not]. 410.8.A & 410.8.D.2 Remember that you must clear the total luminaire including the edge of the trim for the luminaire, not just the rough–in tank. 410.8.A & 410.8.D.3You must also have a closed lens on these recessed tanks enclosing the incandescent bulb. 410.8.B.1

A drawing depicting the clearance requirements of clothes closets can be viewed by clicking on the picture icon to the left.

You are allowed to mount a luminaire on the header above the closet door if you like. Please keep in mind that if mounting a surface mount incandescent luminaire, this luminaire must also have a closed lens containing the bulb, and a clearance of 6”must be maintained from that incandescent luminaire and any adjoining walls due to the heat a bare bulb puts out, plus meet the 12”and 24”clearances of the back and side wall and the shelving.

If designing your wiring for a fluorescent luminaire, you might consider drilling a hole at an angle from approximately 6”off center of the header side to side and then center up and down on the header. Drill this hole at an angle from the surface of the header to enter within the above stud or attic space above that header. You may then run a Romex from the closet light switch through the attic and down through the hole you just drilled in the header leaving a pigtail Romex hanging out waiting for the finished product, after drywall has been installed and when you mount the florescent luminaire on the header. You will find the ballast to be in the center of the florescent luminaire and a knock out for a Romex connector and a wire about 6”off center of the florescent luminaire. This knock out should now land over the wire that you previously installed. This mounting on the header type of installation is about the only way of meeting the minimum safety standards of the NEC, while installing a luminaire in a normal by–pass style shallow clothes closet. Upon your finished product of the structure, the wiring would be totally hidden, and the luminaire would be illuminating what you are trying to see in the closet, because the luminaire would be lighting directly over your head upon your entry into the closet.

Are you installing any of the following, even in your future plans? If so, they can be roughed-in now, with a minimum expense, and finished years later, saving you “bunches of money”; central vacuum, whole-house stereo, cable television, phones surround sound television, CAT 5 computer wiring, etc. The cost of the rough-ins may only be minor to rough-in now compared to a later installation, fishing the wires through closed wall as existing work.

When you buy materials to wire your home, the following may be a fair guess, as to what you might need, if you have a dwelling of around 2,000 square feet, with your designs at a minimum standard wiring design. The NEC requires that receptacles “only”in the kitchen, nook, dining, and pantry to be wired with 12 Awg. conductors. Accepted practice for wiring in a dwelling is to use non-metallic sheathed cable (may be known as Romex).

The rest of the dwelling may be wired in 14 Awg. conductors, with the exception of heavy use dedicated circuits such as water heaters, ranges, and the like. If you decide to use a mixture of 14 Awg. and 12 Awg., then I would guess that you would need about 1,000’of 12/2wGrnd Romex, and 2,000’of 14/2wGrnd Romex, and 250’of 14/3wGrnd Romex. You might want to add 6/3wGrnd or 8/3wGrnd Romex as a minimum for the range, if electric, 10/2wGrnd Romex as a minimum for the water heater, if electric, 10/3wGrnd Romex as a minimum for the dryer, if electric, 14/2wGrnd Romex for the water pump feeder if used, 14/2wGrnd Romex for the gas furnace if used, 12/2wGrnd Romex for the washer, 12/2wGrnd Romex for the dishwasher, 14/2wGrnd Romex for the garbage disposal, if single circuit. The sump pump may be fed by a 14/2wGrnd Romex 430.148 and 430.22

Both the range and dryer must have an insulated neutral in its cable to meet minimum safety requirements. These two appliances use both 120 volt and 240 volt in their internal design, thus creating a need for a current carrying neutral. This conductor must be insulated. Both of these appliances must use a 4 prong receptacle, using a red, black, white and a bare/or green wire contained within that cable 250.134 & 250.138. An example of wiring a four wire dryer or range receptacle, also inside the range or dryer, and the cord connections can be viewed at the following link. "DRYER CIRCUIT WIRING AND HOOKUP"

Remember that a dryer must be 30 amp rated 10/3wGrnd with an “L”shaped neutral connection in the receptacle and a range must be at least 40 amp rated 8 or 6/3wGrnd with a straight neutral connection in the receptacle. The reasons that an insulated neutral conductor must be used with ranges, ovens, and dryers is that in dryers the heating elements are 220 volts not needing a neutral conductor however the motor is a 120 volt motor requiring that neutral to be a current carrying conductor. The range and oven also has 220 volt heating elements that don’t need a neutral conductor yet both of these appliances do have 120 volt light bulbs and electric clocks etc. that must use an insulated neutral conductor.

Existing Ranges, Dryers, Counter mounted cooking units, Wall mounted ovens, Clothes dryers, and junction boxes serving only those listed in this sentence may be wired in a manner as per explained below:

An explanation of the term existing can be found at the following link;


Article 250.140 allows an exception to the 4 wire branch circuit required for new branch circuit installations that are serving those listed existing appliances in the header above if served by an existing branch circuit. If you have an existing three wire branch circuit serving those listed in the above heading such as electric cooking units and electric clothes dryers may remain wired as existing three wire branch circuit, if certain wiring methods match your existing branch circuit serving that certain appliance. You must have an existing branch circuit serving that certain appliance listed above that contains in its wiring design a combined 120/240 volt single phase power source, a grounded conductor that is at least 10 Awg copper or 8 Awg aluminum or larger. The grounded conductor is insulated {with the exception of a service entrance cable [SE cable] which may have a bare grounded conductor.} and only if the branch circuit originates in the main service rated panel {panel containing the main disconnect that controls the entire structure, and not a non service rated panel (sub-panel) and only if that branch circuit remains unchanged as existing wiring. The grounded [neutral] conductor has a bonding jumper connecting the non-current carrying metal frame of the appliance to the neutral connection where the appliance cord connects.

The free standing range and electric dryer is designed to use both 120 volt and 240 volts within its component parts such as light bulbs and motors being 120 volt rated and the heating elements being 240 volt rated. This means that the grounded conductor is a neutral that is carrying the unbalanced return load of both hot conductors. This fact makes the grounded or neutral conductor to be a current carrying conductor. Special safety considerations are required while using this electrical design.

A new range or dryer should have a bonding jumper removed inside the range or dryer located between the center screw of the terminal block where the cord is attached so that the non-current carrying metal frame of the appliance is not in contact with the neutral or grounded leg when a 4 prong receptacle, 4 wire pigtail appliance cord, and a 4 wire branch circuit conductor is installed as required for new installations of this branch circuit as required in 250.134 & 250.138. This bonding jumper will be a metal jumper installed connected from the center screw of the terminal block inside the dryer or range and the connecting to the metal shell of that range or dryer. However if this new electric dryer or electric range is installed in an older home that has an existing 3 prong receptacle, a 3 wire pigtail, and an existing 3 wire branch circuit then it is allowed under the existing rules 250.140 In this new range or dryer installed in existing three wire branch circuit type home wiring then the jumper must either be installed or left installed if already present. Remember this three wire and bonding jumper in the dryer or range only applies with installations of these new appliances in existing older homes. An example of an existing three wire connection allowed can be viewed at the following link "DRYER CIRCUIT WIRING AND HOOKUP"

Special Notes”Remember that if you install more than one motor or motor with other loads on a circuit, whether 14 awg. Or 12 awg., in a dwelling, then any single motor load, by itself, on that multi-motor or multi-use type circuit can not EXCEED 50% OF THAT CIRCUIT. 210.134.A.2

Special Notes” Remember that any circuit, whether 14 awg. Or 12 awg., even in a dwelling, that contains a single motor load on that circuit with no other load must not be with a load exceeding 80% of the maximum rating of that circuit. This rule applies to circuits WITH A SINGLE MOTOR LOAD, ONLY, ON THAT CIRCUIT. 210.23.A.1

All other non-continuous loaded circuits within a dwelling and without any motor loads may be loaded up to 100% of the total amp RATING OF THEIR CIRCUIT’S CONDUCTORS.210.20.A

Special Notes” Remember that you may use a 14 awg. 15 amp, or a 12 awg. 20 amp, rated circuit to feed a single dedicated motor circuit if your motor with no other loads do not exceed 80% of the total amp rating of that circuit. 210.23.a.1. If you are installing a cord and plug piece of equipment then you still may load that cord and plug equipment as long as you do not exceed 80 % of that rated 15 AMP OR 20 AMP RATED CIRCUIT. 250.23.A.1

If you are installing a fastened in place utilization piece of equipment on that same circuit then not fastened in place utilization equipment may be rated and more than 50% of the ampacity of that 15 or 20 amp BRANCH CIRCUIT. 250.23.A.2

Remember a 14 awg. 15 amp rated circuit is even allowed to be installed in the kitchen, nook, pantry, or dining room as long as that 15 amp branch circuit does not serve any receptacles in those room. This 15 amp branch circuit may serve receptacles in other rooms, but this 15 amp branch circuit must not serve any receptacles in the nook, pantry, kitchen or dining rooms. The receptacles in those rooms must be 12 awg and 20 amp rated and are considered as small appliance branch receptacle circuits 210.11.C.1 & 210.52.B.2

If you decide to use all 12 Awg. Wiring , then I would guess about 3000’of 12/2wGrnd Awg. Romex, and 250’of 12/3wGrnd Romex, and 6/3wGrnd or 8/3wGrnd Romex as a minimum size required for a range, if with electric range, 10/2wGrnd Romex as a minimum for the water heater, if electric, [explanation of the workings of an electric water heater can be seen at the following link; "BASIC HOT WATER HEATER OPERATION" 10/3wGrnd Romex for the dryer, if electric, 12/2wGrnd Romex for the water pump feeder, if with water pump, 12/2wGrnd Romex to the furnace, if with a gas or oil furnace, 12/2wGrnd Romex for the following, a washer, a dishwasher, a garbage disposal. Wire sizing may be found for Romex in Table 310.15.B.6for feeders and service entrance conductors and Table 310.16 for all other conductors. Be sure to read the requirement in 110.14.C.1.A concerning all conductors 1 Awg or smaller or less than 100 amp rated to use the 60 degree column found in Table 310.16. You also need to check out 240.4.D concerning ampacity ratings of smaller conductors of 14 Awg rated 15 amp and 12 awg rated 20 amp and 10 Awg rated 30 amps in those smaller sizes of conductors.


The air conditioner equipment should be sized by the manufacturer’s name plate rating, and the conductor size is set by the name plate {minimum circuit ampacity}, as the load rating of the circuit for the air conditioner. The breaker may be sized by the name plate {maximum over-current} as the overcurrent [breaker or fuse] sizing, even though the breaker is larger than the conductor rating in ampacity. This is allowed because the overload of the air conditioner’s hermetic motor is allowed to protect the circuit conductor more accurately. 440.52. If you have question in this area refer to my pass out for HVAC and refrigeration name plate rating, for explanations, and code references seen at the following link; HVAC An explanation about the workings of an Air conditioner can be seen at the following link; "BASIC AIR CONDITIONER OPERATION" If the A/C has no 120 volt usage then this wire may be a two conductor Romex with grounding conductor [black, white, bare] or {black, red, bare} or even a cable with a black, red, white, and bare with the white tapped off as unused.

Any 220 volt appliances that use 120 volt in it’s design, even a single light bulb in that appliance, must have an insulated neutral {white}. All appliances must have an insulated neutral, if there is 120 volt component being used within that 220 volt appliances, such as a 120 volt clock, luminaire, timer motor, etc. utilized within that 220 volt appliance 310.2.A


It was previously suggested that you make a measuring stick by marking the desired height line on that measuring stick with all the different uses of each type of electrical boxes to be mounted. It was also suggested that you use the example boxes that you should have previously nailed on. You should have made a fine line on that measuring stick at the top of each example box, previously nailed on as suggested heights [12”,48”,36”] throughout the dwelling, thus marking that measuring stick with each box usage height.

As we discussed previously, you should have marked each stud that needed a box with the usage of each needed box on that stud with an “R”or “S”throughout the structure. Now using this measuring stick, mark a fine line on each stud needing a box with the box height as needed in matching the box usage. Mark a line on each stud equal to the height representing the usage “R”or “S”that was previously marked. Mark this height line of the type of boxes needed on each stud, throughout the entire structure with its required height.

You are now in need of the electrical material required to wire the house as you desire and also meeting the minimums of the NEC. Once you have the material on the job site, then begin spreading the boxes throughout the dwelling, where they were previously marked for each usage type “R”or “S”. Just go around the structure, and pitch the right style box, as needed [single gang, double gang, triple gang, round light boxes, etc], towards the approximate areas, so that they will be within reach when you attempt to mount them to the structure.

Then mount the boxes as they were marked equal to the height and usage [single gang, double gang, triple gang boxes as needed]. Be careful to be exact matching the thin height line marked equal to the top edge of the box and even with the thin line marked for height. Precise installation is needed in mounting the boxes to avoid a roller coaster affect in the horizontal line of these boxes on the finished product. If the boxes are not exactly on the marked lines and a roller coaster affect happens, then these uneven boxes would stick out like a sore thumb upon the finished product.

Remember to hang the box out to the distance required but just short of the finished wall surface. A ¼”maximum gap is allowed, 314.20 between the wall surface, and the face of the box. Be careful not to stick the edge these boxes out beyond the finished surface, or you will have severe trouble in mounting the receptacle, and switch plates, flush to the finished walls. If you try to grind the box down in order to be flush again with the drywall, you will most likely remove the threads in the screw hole part of the box that your device’s mounting screws use. Be careful, also not to mount the boxes “angled to“the surface of the finished wall due to the above mentioned reason. Remember, you previously set the measuring marks on the studs [height] for the top of the box for ease of mounting the boxes. Set the boxes for the switches, and receptacles, if using ½”drywall, just short of ½”out, straight and even with the drywall surface yet to be installed and even with the pre-marked height. If you are using bakelite boxes take care not to accidentally strike the box, they may shatter on impact. Once all the receptacles, and switch boxes are set, mount all of your light boxes holding them out in the same manner that you did the switch, and receptacle boxes equal to just short of the thickness of the drywall. Remember that you marked the center measurements of the room’s ceiling on the headers of the doors previously in order to speed this process. Now mount the exhaust fans, and recessed luminaire at this time, remember to hold them out just short of the ½”required for the ½”drywall. 314.20

Special Notes”In the bathrooms, this is a small area, and if you are only 1”off center over the bathroom vanity with your light box, that box will stand out, and stare at you, upon the finished product as not being centered. Be exact here ! This exact accuracy is not as important in larger rooms, 1”either way in larger rooms is not normally noticeable on ceiling luminaire, in those larger rooms.

Once all the boxes, and recessed equipment have been mounted, then you are ready to start designing the wiring system. Designing the receptacle circuits take a special amount of calculations. I will try to explain how to do that calculation as follows;


All receptacles in a dwelling are general lighting type receptacles. This is true except those receptacles installed in a kitchen, nook, dining, pantry, or laundry and any appliance circuit that pulls more that 50 percent of the circuit feeding it power. All wiring in a dwelling may be wired with 14 awg copper conductors with exception to the following; Any dedicated circuit or utilization equipment that is rated more than 15 amp rating or exceeds the 50% limit for any one utilization equipment or any receptacle with special 20 amp rating requirements such as any receptacle in a kitchen, dining, nook or laundry that are required to be considered as small appliance branch circuits [few exceptions to the rules apply to these small appliance branch circuit requirements and any receptacle in laundry or bathrooms. These receptacles must be dedicated as laundry receptacles or bathroom receptacles and must be 20 amp rated served by 12 awg conductors.



20 AMP MULTIPLIED BY 120 VOLTS = 2,400 Va @ 100%. ON A 20 AMP CIRCUIT



15 AMP MULTIPLIED BY 120 VOLTS = 1,800 Va @ 100%. ON A 15 AMP CIRCUIT


Measure the outside dimensions of your dwelling living areas, not including the garage [ but be sure to include the finished part of a basement in your total square foot measurements]. Multiply the length times the width of each living area that you measured, and add the total square feet area of each of these living areas together to discover the total square footage of your living areas. That total gives you the total square feet of living space in your dwelling. Now multiply that answer times 3 volt amps. [ approximate watts ]. This total gives you the volt amps [approximate watts] that you will be required to provide for your general lighting receptacles and luminaire. TABLE 220.3.A

Now divide that total volt amps required to serve the living areas general lighting [including convenience receptacles] in your dwelling by either 2,400 Va. if wired by 12 Awg. Romex, or divide by 1,800 Va. if wired with 14 Awg. Romex. The answer you get from that division gives you the total number of general lighting branch circuits, the National Electrical Code requires you to have, serving your dwelling. 210.11.A and .B and TABLE 220.3.A

Now add all of the general use receptacles [this means all receptacles not including dedicated circuits, and any receptacles in the kitchen, nook, dining room, pantry, or laundry].210.11.C

Now take the total number of general use receptacles, and divide that total by the number of general lighting branch circuits that you figured, as required. This will tell you the maximum number of general-use type receptacles that you may put on each general-lighting branch circuit. 211.B


Special Notes” If you meet the 6’/12’rule 210.52.A.1 as a minimum in a bedroom, you might average around 5 or 6 receptacles per bedroom. Of those 5 or 6 receptacles you probably would only actually use 2 o3 receptacles. The average loads in the bedroom would probably be maybe a television, stereo, alarm clock, table lamps, etc. these are very light loads. The total receptacle load in the average bedroom would not normally be over maybe 4 amps.

Now let’s install a receptacle on every stud in that average bedroom we now might have 50 to 75 receptacles or more. How many receptacles would you use now ? Maybe the same 2 or 3 ?

This is why the NEC allows the calculations mentioned above as the method of calculation to find the receptacle circuitry design.

Those extra circuits you were planning on serving the bedrooms may be of better design usage if installed in the kitchen or laundry areas. These areas are where the heavy loads are normally found.


The above type of wiring design method is not acceptable in the kitchen, nook, pantry, or dining rooms. These rooms have requirements “special to their own use”as I will explain in the following;

The kitchen, nook, pantry, and dining room receptacles must have 12 Awg. wiring. 210.11.C.1 All receptacles in the kitchen, nook, pantry, and dining rooms may be intermixed with each other, and are considered as the small appliance branch circuits. 210.52.B.1 Small appliance branch circuits include all general food use type receptacles in all of these food rooms, whether they are over a counter, or not 210.52.B.1 The refrigerator, or the receptacle device that ignites your gas range or cook top , or a clock receptacle may be installed on the small appliance branch circuits, without further load calculations. 210.52.B.2. Exception 1 and 2 No other outlets whether lighting, fixed appliances or anything in any other room may be installed on the same circuit with any receptacle located in the kitchen, nook, dining, or pantry. 210.52.B.2

You must have at least two small appliance branch circuits {serving the small appliance branch “use food type”receptacles}, available over the kitchen counters. 210.52.B.3 and 210.11.C.1 You may mix these small appliance branch “use food type”receptacles over the counter, with the small appliance branch “use food type”receptacles in the kitchen, nook, dining, and pantry that are not over the counters. 210.52.B.3

Keep in mind that the cook will probably not cook in the dining room, nook, or pantry, at the same time that they are cooking in the kitchen. This also, is expected to be the same scenario in the nook, dining, and pantry. 210.52.B.3 When they are serving in those rooms, they probably will not be using the receptacles in the kitchen, at the same time. The cook will most likely unplug the appliances in the kitchen and move them to the nook or dining room in order to make serving time more efficient.

The two small appliance branch circuits are left to the design of the electrician. Keep in mind that a cook will probably be cooking, centered tightly, in one certain area. I would like to advise that you might want to rotate these circuits in a wiring pattern such as every other receptacle on a different small appliance branch circuit. A example of this alternating style wiring would be the 1st, 3rd, 5th, 7th receptacle on circuit “A” and the 2nd, 4th, 6th, 8th receptacle on circuit “B”. This design would serve any tightly centered cooking arrangement centered over the kitchen counter with two separate small appliance branch circuits available, within reach, of the person cooking in one spot on the counter. This style of wiring of alternating receptacles on a circuit is not required by the Code, but should make good sense.. Remember that the NEC is the minimum safety standards required to be met. I doubt that I would want to wire my home just meeting the minimum, but that is your choice. You have to just meet the minimum safety standards set forth by the NEC. An example of wiring by the minimum safety standard which I would accept, but would not advise, are as follows. The Code implies that if you put all of the small appliance branch “use food type”receptacles in the kitchen, dining, nook, and pantry on one small appliance branch circuit, including the refrigerator and all of the receptacles over the kitchen counters, except one counter receptacle. Then if you put that one other receptacle over the kitchen counter on a second 20 amp circuit, creating the second 20 amp circuit as required, you would successfully meet the minimum safety standards. This style of designing the small appliance branch circuits would meet the minimum safety standard, but I would not advise this design. 210.52.B

An example of an alternating receptacle circuitry can be viewed by clicking on the picture icon to the left.


Any fixed appliances, usually direct connected with a Romex connector, and / or any lighting, and / or anything in any other room, except the receptacles in the kitchen, nook, dining, and pantry as mentioned.


Small appliance branch circuit is any readily accessible receptacle installed in the kitchen, nook, dining, pantry rooms whether over the kitchen counter or not. 210.11.C.1 and 210.52.B Dishwashers are not allowed to be installed on the small appliance branch circuits. Garbage disposals are not allowed to be installed on the small appliance branch circuits. Sink luminaire or any other type of lighting are not allowed to be installed on the small appliance branch circuits. The exhaust fan over the range is not allowed to be installed on the small appliance branch circuits. Any of the following; any permanently mounted appliances such as a trash compactor, microwave in a microwave cabinet, etc. are not allowed to be installed on the small appliance branch circuits. Remember that a small appliance branch circuit is any convenience receptacle, anywhere within a kitchen, nook, dining, or pantry. 210.52.B and 210.11.C.1 Remember that you have a few exceptions allowed to be on the small appliance branch circuits and are as follows; the receptacle serving the receptacle providing power to the devices that ignites range burners built into a gas range, a clock receptacle, and a refrigerator. 210.52.B.2 Exception 1 and 210.52.B.2 Exceptions 1 and 2 Remember that you can install a single circuit to serve the refrigerator, and dedicated as a refrigerator circuit, on a 15 amp dedicated circuit. 210.52.B.1. Exception 2

There is an exception allowing a switched receptacle from a general lighting circuit to be on a 15 amp circuit in the kitchen, nook, pantry, and dining room. This receptacle is allowed to fulfill the requirement of a switch controlled lighting outlet, luminaire or switched receptacle, in the dining room, but must not be accredited as the required small appliance branch receptacles.210.52.B.1 210.70.A.1 This 15 amp receptacle used as a switched receptacle does not fulfill the requirements of the 6’/12’rule requirement for the small appliance branch circuit in the dining room. 210.52.A A small appliance branch circuit must not be switched. 210.70.A.1 and 210.52.A


Your garbage disposal pulls approximately 9.8 amps, and may be installed on a 15 amp rated circuit with other loads or as a dedicated circuit, even if found in a kitchen. This is true with this motorized fixed appliance, or any other motorized fixed appliance, even though it is found in the kitchen, or bathroom, or laundry, or anywhere else in the dwelling, as long as this motor type circuit does not include any small appliance branch circuit receptacles, laundry receptacles, or a dedicated bathroom receptacles circuit serving all the bathrooms. 210.23.A. Exception and210.11.C.1 and 430.22.A These same 15 amp rated circuits may possibly be on a circuit with other loads, such as lighting, just so long as they are not a small appliance branch circuit receptacle 210.23. Exception and 210.11.C.1, and not the laundry receptacles, 210.23.A.2 and210.11.C.2 and not dedicated bath receptacles circuit serving all of the bathrooms. 210.11.C.3 You can put any fixed appliance containing a motor on a 15 or 20 amp rated circuit with no other loads as long as this fixed appliance does not exceed a load of 80% of that 15 or 20 amp rated circuit,210.23.A.1 and 384.16.D and the conductor is rated at least 125% of the full load amps of the appliance. 430.22 You can put any fixed appliance containing a motor on a 15 or 20 amp rated circuit with other loads, on the same circuit as long as any one motor installed on that circuit does not exceed 50% of the total rated load of the circuit. 210.23.A

An example of motors and other loads could be as follows. You could install the range hood, or any other motorized appliance, on a general lighting branch circuit from a living room or bedroom, such as receptacles or luminaire in these habitable rooms, even on a 15 amp rated 14 Awg branch circuit, as long as that motor did not exceed the 50% maximum motorized appliance load for any one motor on that circuit, and did not mix receptacles in the kitchen, dining, pantry, laundry, or bathrooms, on the same circuit. 210.52.B and 210.23,A

Your dishwasher pulls approximately 17 amps, and must be a dedicated circuit on a 20 amp rated circuit, because it exceeds the 50% maximum load of a motor on a circuit designed to be with other loads on that same circuit. 210.23.A There is a rule that allows the “Authority having Jurisdiction”, your Inspector to rule two motors such as a garbage disposal and that dishwasher to be on the same circuit. It is called a non-coincidental load rule. This rule allows your Inspector to allow special consideration to a specialty circuit. I allow the garbage disposal and the dishwasher to be on the same circuit because the garbage disposal would not usually run long enough to affect the overcurrent device protecting that circuit. I feel that a garbage disposal would only normally run approximately 30 seconds. This would almost not be noticed at all. Please check with your “Authority having Jurisdiction”before utilizing this non-coincidental load rule. 210.21

Remember that a 10 Awg. conductor can be loaded to a maximum of 30 amps, a 12 Awg. conductor can be loaded to a maximum of 20 amps, a 14 Awg. conductor can be loaded to a maximum of 15 amps. 210.40.D.3 The loading of the circuits in a dwelling may be rated at 100% for everything 220.3.B.10 but motor loads which are rated at 80% on a dedicated circuit. 210.23.A or 50% load of any one motor on circuits with motors and other loads 210.23.A The “if specifically otherwise permitted”statement in the NEC refers to motors only. 240.3.E through G. If you are serving a motor, then you may use the chart in Table 310.16 or Table 310.15 if a feeder in a dwelling allowing 20 amps on 14 Awg., 25 amps on 12 Awg. and 30 amps on 10 Awg. This is true with motors regardless of the temperature rating of the insulation of the conductor due to the terminal limitations of 60 degrees centigrade of the terminals used in the circuits, unless the conductor is rated over 100 amps. 110.14.C.1 If the conductor is rated over 100 amps then you may use the 75 degrees centigrade column because of the 75 degree rating of the larger 100 amp rated terminals. 110.14.C.1


An explanation of voltage drop calculations can be viewed at the following link;


Remember, as a rule of thumb; Do not go over approximately 125’of wire without considering a voltage drop for 120 volt circuits, and approximately 250’of wire on 240 volt circuits throughout the property. Now in order for you to meet the minimum safety standards set by the Code, you shouldn’t have to worry about voltage drops of general lighting circuits and / or several receptacles on a circuit that are inside a dwelling. This is due to the inherent design requirements of the NEC concerning dwellings and their detailed loading design requirements of the NEC as a minimum wiring design. It may however, be to your advantage in regard to your future Utility bills, whether inside your dwelling or outside your dwelling, to consider voltage drop on certain circuits. You might want to consider voltage drop affects for any of your automatically operated or continuous usage equipment throughout your property concerning your wiring designs. This voltage drop concern and unknown future loads being plugged into the general use convenience receptacles is why often times people will install 12 awg wire throughout the general lighting branch circuits. This tends to avoid dimming of lights when future heavy loads are used on convenience outlets such as irons or hair dryers, etc. The minimum size conductor required for general lighting style convenience receptacles and luminaire is 14 awg. Most commonly people oversize to 12 awg as a minimum wire size. 12 awg copper conductors are not required to meet the minimum safety standards for convenience outlets and for luminaire for general lighting, but seems to make good sense.

Voltage drop is a controversial minimum requirement in the NEC. It is generally accepted that voltage drop requirements are “advisory only”with the exception of the following requirement. You must increase the grounding conductor where the branch or feeder conductor is increased in size due to a voltage drop that is present in a circuit. 210.19.Exception and 250.122.B and 210.19.A.4 and 215.2

I feel that we should interpret the NEC as if it allows for no voltage drop. 210.19.A.4 The way that I feel is that we should interpret the NEC by reading this section as if the conductor must be capable of carrying the load. This should be interpreted as no voltage drop allowed, at all. The FPN note could then be used as an allowance in your wiring design that can be approved by allowing the 5% voltage drop. The FPN Note which is advisory in Indiana will advise for a limited allowance of 3% on a branch or a total combined voltage drop of 5% for both the feeder and branch combined.

Where voltage drop is calculated, voltage drop must be calculated from the serving transformer to the end of line of a feeder or branch circuit conductor or both combined, whichever section that you are calculating. I guess the decision is up to you, as to whether you should worry about voltage drop or not. As long as you stay within the 5% suggested in the FPN note then I feel you should be all right. I feel that anything over the 5% should be a concern to you. Just keep in mind that voltage drop is electricity that we pay for, but do not get to use.

Also consider that the higher the voltage drop equals the lower the voltage available to run your equipment. If the voltage is less than the equipment is designed as needed for the equipment to run, then the amps needed to run the equipment will increase when motors are concerned. The lower the voltage the higher the amps concerning motors. If concerning resistance heat the lower the voltage the less heat produced by that heating unit. Concerning motors the higher the amps the higher the heat of the equipment. The life expectancy of the motorized equipment will decrease equal to the lower the voltage due to the fact that motor will have to work harder to do the same work required of it causing excessive heating of that motor. This lower voltage will cost you more money to run your equipment, and the lower voltage causes excessive heat which can damage your motorized equipment and shorten the life or your motorized equipment.

An example of the affect of voltage drop on your pocket book would be the following, in approximation. If you have a 125 volt ½ horse power rated motor designed to operate with a full load amps of 9.8 amps Table 430.148, and if you had a voltage drop of 20%. This wiring design would equal approximately100 volts available to serve the motor designed to run on 125 volts, causing excessive heat . Then instead of the motor pulling the expected 9.8 amps, the motor will now be pulling approximately12.25 amps while considering the lower voltage available to do the same work product that the motor is designed to produce.

If we take the same motor at 125 volts with a load of 9.8 amps and with an approximate charge of 10 cents per Kw. usage from your power company, and running the motor 24 hours a day, for 30 days of the billing cycle. You would be charged approximately $ 88.20. If we ran that same motor with 100 volts with a 20% voltage drop the same amount of time at the same rate per Kw cost, you would be charged approximately $110.50. This would be an increase of electric usage cost of $22.05 per month or $264.60 per year for the same motor to do the same amount of work. This increase of cost is caused by loss of the electricity that you paid for but did not receive due to a voltage drop inherent in your electrical design.

As you can see just increasing the conductor size one size larger to address your voltage drop could save you money. This one time increase of cost during the initial installation of your larger wire during your initial installation could save you more on your electric bill in one year’s use of your equipment, than the increased cost that you experienced to pay for the larger wire initially installed. Then you could experience this same annual savings every year during the life of your home. An example of this type of excessive inherent cost that you should consider due to your wiring design causing an excessive voltage drop in your home would be your furnace, your pool pump, your heat pump, your refrigerator, your electric water heater, etc. You would experience different savings on each appliance, but the calculations of voltage drop in your wiring designs should be worth your time. This is due to the automatic running of your equipment, off and on, 24 hours 7 days a week, whether you are there or not, or like a pool pump running non stop 24 hours a day 7 days a week.

I wrote the above paragraphs hoping to paint a picture in your mind as to how a voltage drop can be reduced and how addressing a voltage drop could save you money. I also wanted to show where you may design a circuit addressing your voltage drop causing cost savings well worth your time to investigate.

You also could use a step-up transformer in order to reduce the voltage drop present at end of line, instead of increasing the conductor size. Any means of adjustment in your wiring design should be acceptable that is above the minimum set by the NEC.

Now you should see why some people pay more per month on the electric bill than others do. The life style of your family, leaving coffee pots on, increasing the thermostat of your water heater, furnace, air conditioner, etc. can cause you to pay more than your neighbor that has the exact same house. Voltage drops present in your original wiring design will cost you more money on your electric bills than your neighbor pays for a house that is exactly like yours but wired by a different electrician with voltage drop considered when they wired your neighbors home. You could pay more on your electric bill than your neighbor and be more frugal on your equipment usage then your neighbor, just because you didn’t consider voltage drop when you wired you home.

The formula to calculate a voltage drop concerning single phase wiring in your wiring designs is

Voltage Drop = 2xKxLxI


The “2”stands for the wire going from the panel to the equipment {hot}, and the second wire returning the path back to the panel {grounded} for 125 volt circuits. For 240 volts circuits the “2”stands for the two hot conductors running to the equipment. No return path would be required for 240 volt circuits with no neutral conductor carrying the unbalanced load. If you have a circuit that has two hot conductors and a white or gray conductor then you would have a 240 volt multi-wire circuit. A 240 volt multi-wire circuit would be calculated as two 125 volt circuits, because the white or gray conductor is no longer just a grounded leg {return path}. This conductor is now a neutral conductor that carries the unbalanced load between the two hot conductors. In most occasions you would not experience a three phase circuit in a dwelling setting. If you do have a three phase circuit then you must substitute “1.732”in place of the “2”to calculate a three phase voltage drop. The “1.732”stands for the square root of the three hot conductors used in a three phase circuit.

The “K”stands for the resistance of your conductor per 1000’found in the NEC Chapter 9 Table 8. To find “exact K”you would calculate the resistance of your conductor size and type then multiply times the circular mill of your conductor then divide by 1000. This would be “exact K”. “Approximate K”would be 12.9 for copper or 21.2 for aluminum.

The “L”stands for the distance one way from your power source {transformer} to your equipment.

The “I”stands for the load in amps of your equipment. Then divide this answer by the circular mill of your conductor found in the NEC Chapter 9 Table 8. Examples of voltage drop calculations can also be found in the NEC handbook in Chapter 9 Table 9.

You might plan to reduce your wire size in a circuit that you are wiring to save money {cost}, or voltage drop {using the larger conductor at the beginning of a circuit then reduce the size at the end of a circuit. You could use the following as an example of a conductor being reduced, in size, in a circuit. You might run into this different conductor sizing in the same circuit if you tried to run 12 Awg. from a panel, then run 14 Awg. to your switch legs to save money. If you do reduce a wire size in a circuit, you must reduce the overcurrent device size to meet the maximum allowed overcurrent device {breaker or fuse} to meet the maximum ampacity of the smallest conductor in the circuit. Be careful doing this type of design. You may not meet the minimum ampacity required on a circuit such as a 15 amp fuse or breaker on a 20 amp circuit that is required in the kitchen, bath, and laundry. 210.3


You may make a junction almost anywhere you like, keep in mind that you must keep that junction accessible. 314.29 Junctions must be contained within a box. 300.15, and must be with a legal connections {compression style connection} 110.14.A Be careful about using junction on resistance heat, and heavy motor loads. These are trouble areas due to deterioration caused by the excessive heat of larger or continuous loads.

Remember that you must not use conductors smaller than 14 Awg for structural wiring. You must not use voltages above 120 volts to ground, in a dwelling. 210.3


Watch that you don’t overfill the junction boxes. 314.16 such as switches, receptacles, or junction boxes, etc.



We must first find the maximum numbers of conductors allowed in the box that you are using.

When you are calculating the total number of current carrying conductors in a box, in addition to counting all actual current carrying conductors as one current carrying conductor for each conductor {any color of conductor except, green or bare}, you must add the following as current carrying conductors as follows; Article 314.16.B Each device {switch or receptacle} found in the box must be counted as 2 more current carrying conductors, all grounding conductors in that box must be counted as a total, as one more current carrying conductor, and all clamps must be counted with the total number of clamps found in the box as one more current carrying conductor. Keep in mind that you are not supposed to count conductors that neither enters your box nor leaves your box. [pigtails only, these are ignored].

If you are using a steel box that is listed in the NEC chart 314.16.A, then the chart should give you the maximum current carrying conductors allowed in the steel box. A further calculation of adding up the number of current carrying conductors that you must count as being in that box, by your wiring design must be calculated. The total number of current carrying conductors that you designed to be in that box must be compared to the maximum allowed in that box. The total number of current carrying conductors that you designed to be in that box must not exceed the total number of current carrying conductors allowed in that box.

You may also use the following method of calculation if you don’t have a Code book, are using a size of steel box that is not listed in chart 314.16.A, or you are using a plastic or fiber box. If you are using a type of box that is not listed in the NEC chart 314.16.A, then you must measure the box, then multiply the height times the length times the depth of the box to find the cubic inch capacity of that box. Now you must look in the NEC chart 314.16.B to find the cubic inch required per conductor rated by the size of the conductor that you are using. The chart mentioned says that 14 Awg. = 2 Cu. In. per conductor, 12 Awg. = 2.25 Cu. In. per conductor, 10 Awg. = 2.5 Cu. In. per conductor, 8 Awg. = 3 Cu. In. per conductor, 6 Awg. = 5 Cu. In. per conductor. 314.16.B If you are using all conductors of the same size in your box, then you must count the number of current carrying conductors [all colors including white but not counting green or bare] entering your box. Also do not count conductors that neither enters your box nor leaves your box. [pigtails only, these are ignored].

Now add to your number of current carrying conductor list, by counting all of the grounding conductors as one conductor [green or bare], no matter how many grounding conductors, just add the one conductor to your total number of current carrying conductor list. All grounding conductors [green or bare] must be counted as a total of one current carrying conductor.

Clamps are also counted the same as grounding conductors, one current carrying conductor must be added for the total of all clamps found in the box. All clamps found within your box that are entering the box at least ½”, no matter how many, count as one current carrying conductor, only, for all of these clamps. Now add this one conductor count to your total number of current carrying conductor list, if any of these clamps are present. A single gang plastic or fiber box will have no clamps to consider. They are exempt from a clamp requirement.

Devices must count as 2 conductors for each device. Count the number of devices {switches or receptacles}. Multiply the total number of devices times 2. The answer from multiplying the total number of devices by the 2 is the total number of current carrying conductors you must add to your total number of current carrying conductor list.

Now this final total of your current carrying conductor list is the answer to the total number of current carrying conductors installed in your box.

Now multiply the cubic inch required for the size of conductors in your box found in the 314.16.B by the answer that you found in your total number of current carrying conductor list. This is the total cubic inch required for all of the conductors, equipment, and devices in your box. Compare this total cubic inch required to the total cubic inch capacity of your box. You must not exceed the capacity of your box with the total cubic inch required by your conductors, equipment, and devices that you installed in that box.



If you are using different size conductors in the same box. You must perform the same conductor count and calculation as if using all of the same size conductors in your box as described above except the following. You must change the current carrying conductor calculation into separate calculations for each size conductor times the assigned cubic inch required in the 314.16.B. You must also change the counts calculation for your devices and clamps calculating them as if they were the largest conductor in the box, when you use the 314.16.B. Ignore any smaller conductors for the device and clamps calculations section. Only consider these equipment and devices as the largest size conductor present in your box to calculate the current carrying conductors that you must add to your list for these equipment and devices. You must also change the one conductor count for the total number of grounding conductors using the largest grounding conductor size found in the box, when you use the 314.16.B.

Then add all of the cubic inch requirements from your list, all added together, for the total cubic inch required and compare that total cubic inch required to the cubic inch capacity of your box. You must not exceed the total cubic inch capacity of the box by the total cubic inch required for the conductors, equipment, and devices present in your box, as you have calculated.


If you have boxes with conductors larger than 4 Awg. that are installed in a box, then you must calculate in a different manner. In short, a box with 4 Awg. or larger conductors with “U”or angle pulls the box fill must be calculated by adding the diameter of all of the conduits on the same side of the box and in the same row for the first total. Then add each row installed on that same side of the box. Now pick the largest one row total, of each of the rows, and use that in your calculation. Ignore the other rows on that side of the box not in that same row. 314.28.A.2 Now pick the largest conduit in that largest row and multiply that conduit diameter times 6. 314.28.A.2 Now add the total diameters of all of the conduits in that same row to that times 6 multiplication answer. 314.28.A.2 Ignore all of the other rows on that same side. This answer is the minimum distance in inches that the opposite wall of that box must be from that side that you calculated. 314.28.A.2 Now calculate each side of the same box for the answer to the distance required to the opposite wall of the box from each side that you calculate. This is the size of box required to contain the 4 Awg. or larger conductors. 314.28.A.2

There is a minimum distance allowed between the conduit on one side of a box that contains a conductor going to a conduit on an adjacent side of the box in an angle pull, or the same side of a box in a “U”pull. You must take the largest of the two conduits containing a conductor of an angle or “U”pull and multiply that conduit by 6. 314.28.A.2 The answer to this multiplication would be the minimum distance between two conduits containing the same conductor in an angle or “U”pull. 314.28.A.2

If you are using nonmetallic sheathed cables with 4 Awg. or larger in them then you must measure the widest point across the nonmetallic sheathed cable and treat this measurement as the diameter of a conduit in your calculation. The intent of the nonmetallic sheathed cable widest point is to find the size of conduit required to contain than nonmetallic sheathed cable. The calculations to discover the size of a box with 4 Awg. or larger conductors gets more complicated but it should give you a general idea on the subject.314.28.A.2


You must have 18”clearance from the back and side walls of a clothes closet from the nearest edge of the recessed tank trim. You also have to meet another clearance requirement of 6”from any shelf in the clothes closet to the nearest edge of the recessed tank trim of the luminaire.410.8.D.1

You must have 18”clearance from the back and side walls of a clothes closet from the nearest edge of the florescent luminaire. You also have to meet another clearance requirement of 6”from any shelf in a clothes closet to the nearest edge of the florescent luminaire. 410.8.D.2

You must have 24”clearance from the back and side walls in a clothes closet from the nearest edge of an incandescent luminaire. You also have to meet another clearance requirement of 12”from any shelf in a clothes closet to the nearest edge of the incandescent luminaire.410.8.D.3

Any incandescent luminaire whether surface or recessed must be with a closed lens enclosing the incandescent bulb or bulbs. 410.8.C

A drawing depicting the clearance requirements of clothes closets can be viewed by clicking on the picture icon to the left.


You must install a fan to a box approved and listed for use in supporting a paddle fan. Any box listed and approved for the purpose, should be built like the following; The Code does not want you to rely on the tabs normally threaded to accept the 8/32 support screws. Instead, that tab will have a larger hole letting that 8/32 screw slide through to the back of the box to threads in the back of that box. This box will be threaded in the back of that box, if steal, or the box will have a nut molded in the back of the box, if it is plastic. This type of box, listed and approved for a fan, may be available in plastic or steel. These fan boxes may even be pancake boxes listed and approved for use supporting a paddle fan. 422.18 and 314.27.D


Smoke detector requirements are found in the CABO Residential Building Code Book. These smoke detector requirements were adopted by the State of Indiana as the rules to govern by the Authority Having Jurisdiction. The smoke detectors are required to be installed in a permanent manner. The smoke detectors are required to be 120 volt powered, and with battery back up. These smoke detectors are required to be installed within each bedroom, in the vicinity of each bedroom area {hall}, and at least one on each floor including a basement. These smoke detectors must be 120 volt powered with a red or yellow conductor that ties all smoke detectors together on a third wire so that if one smoke detector sounds off then they all must sound off. When it comes to the smoke detector rule, the term existing does not apply. This smoke detector rule applies to all dwellings.



Cabling is when you run several nonmetallic cables {Romex} together in a group for a distance of more than 24”. 310.15.B.2

Normal holes drilled in a floor joist with several cables running through a series of floor joist holes is not considered as cabling requiring any de-ration calculation because these cables lay loosely in between those joists. Now if you installed the same cables using wire ties to bundle them tightly together then you WOULD be considered as cabling requiring the ampacity de-rations as described above.


Check the writing on the side of the pump wire. This wire must be marked as listed for use as a pump wire. If the pump wire is rated as type XHHW, THW or TW, the conductor is approved for a wet location. 310.8.C This pump wire is not approved to leave the protection of the earth without being protected by a conduit. This pump wire is allowed to be direct buried, if marked “pump wire”. The pump wire designation says it is approved for direct burial without a conduit protecting it while in the earth. Type XHHW, Tw and Thw that are approved for use as a pump wire, is approved in a wet location but must be protected by a conduit if leaving the protection of the earth. Otherwise, without the pump wire designation, you must use a wire marked with a “U”designating approved for direct burial. Table 310.15 If you use a pump wire, the wire must be protected by a conduit, all of the way to the load after its leaving the protection of the earth. Table 310.15 You may transfer the pump wire to a Romex cable {type nonmetallic sheathed cable} upon entering the crawl space and leaving the earth. You may then continue on to the pressure tank without protection if you change to Romex upon entering the crawl space. The type UF cable if used instead of the pump wire is equal to the pump wire and the Romex cable {nonmetallic sheathed cable}. Type UF cable can run from the submersed pump motor in the well under the water to the pressure tank without protection at any point unless subject to physical damage. Subject to physical damage would be if you surface from the trench outside then pass into the dwelling from the outside. 340.10 and 340.12 While it is down low to the ground and outside it is considered as subject to physical damage and must be sleeved in a conduit. Type UF cable must be supported as per the NEC requirements for Romex upon entering the structure. {every 4 ½ feet}334.30 The pump wire may not run unprotected once leaving the earth or in the crawl space unless it is type UF with an outer covering like a Romex cable in design.

Check to see if the capacitor bank is built into the motor. If the capacitor is in the pump and not in the dwelling, near the pressure tank, then you may run only two insulated conductors to the pump. If the capacitor bank is remote from the pump itself, then three insulated conductors must be ran. All current carrying conductors including neutrals and grounded leg conductors must be insulated. 310.2


You may run your wires within the studs, within the attic, within the crawl space, within the areas between the first floor ceiling, and second story flooring. 334.10 You may even run the nonmetallic sheathed cable on the surface as long as there is not a danger of physical damage. 334.10.A.1 If you run surface on the wall, most people consider above 4 feet or behind an object protecting such as a large plumbing pipe would be not subject to physical damage. Behind a large appliance is consider subject to physical damage because the appliance itself could damage the Romex. There is no limit stated in the number of stories high you may install nonmetallic sheathed cable anymore with the thought in mind that 334.10 limits you to wood structures that are limited to a maximum of 5 floors in height above finished grade. 334.10

When running within the walls, and between the ceiling, and flooring, you must keep the holes beyond 1 ¼”from the surface 300.4.A.1, or protect that wire, from damage, with a 1/16”steel plate. 300.4.A.1 You may run your wires within a cold air duct, only if running across it {perpendicular}, and not along it {parallel}, while within the duct.300.22.C.Exception You may run more than one wire per hole, anywhere you normally would run one, but be careful not to create a cabling effect. If a cabling effect happens, then you must de-rate the wire, according to 310.15.B.2, counting each conductor, within each cable, with the exception of the grounding conductor. If cabling happens {cabling = several Romex cables running through a series of the same line of hole, for more than 24”} then you will de-rate the ampacity of these cables quickly. A 20 amp circuit will quickly become a 5 amp circuit or less, even though that wire was originally rated at 20 amps. Table 310.15.B.2.A Do not use cable ties to bundle Romex for a distance of more than 24”because you would again be creating the cabling effect again. An example of calculating ampacity of a conductor can be viewed at the following link: "AMPACITY" A short short article that may also help you in calculating Romex in conduits and cabling can be viewed at the following link that a friend of mine wrote named John Nelson. My thanks to John Nelson for allowing me to link to his article. MULTIPLE NM-B CABLES THROUGH A 2" EMT CONDUIT"


If you plan to wire running, up the studs, and through the attic, then I suggest that you use an auger bit, around 7/8 to 1”size. I suggest that you drill one hole through the top plate, over each receptacle and single switch box. Now, drill two holes, over each double switch box. Then drill three holes over each three or four gang switch box. This is a nice wiring style, and I suggest that this style of wiring should be considered, if possible

If you plan to wire through the crawl space, then drill the same number of holes through the bottom plate. I don’t suggest this type of wiring style because it creates a lot of crawling, and a lot of supporting of the wires, in the crawl space that will hang like sway back clothes lines, without the required support. This style of wiring creates a lot of extra work supporting the hanging wires in the crawl on running boards. 334.15.C You must install the Romex running along the framing members or on running boards. 334.15.C

If you plan to wire through the studs, then I suggest that you place the drill against your hip, both for support, and even hole placement. I suggest that you drill one hole per stud, unless you know that a lot of wiring will be installed across a certain wall, and adjust as necessary. You should drill your holes as straight as possible, for ease of pulling the wires through those holes. You will need to take special consideration, at the corners. You can turn a corner by drilling both directions making the holes meet within the corner studding. When you pull a wire around this type of corner, you must bend the wire to a form a curve in the wire, then wiggle it through the holes drilled in that corner. It get easier the more often you install a wire through the holes in the corners.

Joist and rafter must not be notched in the middle third of a framing member, and the notch must not exceed 1/6th the depth of the framing member. CABO 3902.1 and 502.6 Joist or rafters must not be drilled within 2”of the surface of the framing member and the hole must not be drilled with the hole larger than 1/3rd the width of the framing member. CABO 3902.1 and 502.7


Please keep in mind that you must size your breaker in the panel protecting that circuit to the maximum ampacity of the smallest conductor found in that circuit

As you design your “switch system”wiring pattern, you should consider running the power runs from the service panel or other box into switch boxes. This will allow you to make it more convenient to split off in a wye pattern to feed other boxes. Receptacles, in single receptacle boxes, take up too much room in the box to run more than one power out from that receptacle box to other boxes. Also, running more than one power out from a receptacle box also requires wire nuts not needed if no power outs exist in that box, except the wire nut for the grounding conductor. Putting power ins and power outs in the switch boxes will allow you to be able to, more easily, keep within the maximum box fill requirements, and still not have to fight to install the devices of that box. This is especially true in multi-ganged boxes such as triple and four gang boxes which have more cubic inch capacity. 314.16.B

An example of using switch boxes can be viewed by clicking on the picture icon to the left.

You should consider designing a three, or more way switch system, by the following suggestions. These suggestions will allow you ease in remaining within the box fill maximums. Run a cable with two insulated conductors in it as power to one of the end switch boxes, of the three way switch system. Consider this the start of the system. Then go from that box to the next switch box, within the same switch system, using a cable with three insulated conductors. This will be the other end, of that three way switch system. Now run a two conductor cable from that end switch box to the luminaire. This will be the switch leg box which is the box at the opposite end of the three way switch system that you ran the power into.

An example of wiring in this manner can be viewed by clicking on the picture icon to the left.

Now to repeat, in short what we just said; From power source to the first switch box , then from the first switch box with the power cable in it to the second switch box , then from the second box with the three conductor cable in it to the light box , then from the first light box to the second light box, if more than one luminaire is controlled by the same three ways switch system. Congratulations ! You wired your first three way switch system. Remember that in this wiring design on this switch system the white wire in a 12/3 or 14 / 3 cable, that contains a black, red, white, and a bare, must be used as the grounded conductor only and the bare or green conductor must be used as the grounding conductor only. 310.2

If you wire nut the white wire of your power source going into the first box to the white wire in the 12 /3 or 14 / 3 cable, then the white wire of the 12/3 or 14 / 3 cable entering into the 2nd box to the white wire of the 12/2 or 14/2 cable going to the luminaire, you would just be extending the white wire of the power source from the first box through the 2nd box to the luminaire.

This will leave you two blacks and one red in each box to connect to your three way switch. You should take the black of the 12/2 or 14/2 cable supplying the power coming into the first box and connect this black of the 12/2 or 14/2 cable to the common screw. {black screw} Then connect the black and red of the 12/3 or 14/3 cable coming into that box to the two traveler screws of the three way switch. {two copper screws} These two travelers may be installed on either of the two copper screws on the three way switch that is not marked common {black screw}. 200.7.C.2

If the switch system is a four or more way switch system then run a two insulated conductor {12/2 or 14/2} cable from a power source to the first switch box of a four or more way switch system, then come from that first box and go to the next nearest switch box, within the same switch system using a cable with three insulated conductors {12/3 or 14/3}. Now go to the next nearest switch box again using a three insulated conductor cable {12/3 or 14/3}, and repeat from the switch box to switch box with three conductor cables {12/2 or 14/3}, until you have reached the last switch box designed for the switch system. This last box should be nearest to the luminaire. You should, then, run a cable with two insulated conductors {12/2 or 14/2} from the last {other end} switch box, of this certain switch system, to the luminaire, as a switch leg allowing all of the locations, of this certain switch system, to control the luminaire in an unlimited manner. An example showing wiring of a four way switch system can be viewed at the following link [you may add more four way switches as you like if you desire more than three places to control a light by wiring the added four way switches same as the middle switch in the schematic. "4 WAY SWITCH WIRING"

Most single gang plastic, and fiber boxes will hold three 12/2 cables or two 12/2 cables and one 12/3 cable. and be within the Code’s maximum box fill requirements, even with a receptacle or switch in that box. Use this “Rule of Thumb”method, in your design to maintain ease of design or refer to Table 314.16.B of the NEC. I suggest that you use your double, or larger switch boxes, if you want to branch off into two or more directions. These larger boxes allow more conductor fill, thus permitting you to branch in a “wye pattern”with your power ins and power outs in more than one direction on the circuit. You may also use a light box as a junction box, if necessary, but I suggest that you run power to the switches, and then a switch leg, only, to the light box. You should experience less confusion, if you keep your power ins, and power outs, at the switch box locations.

In 2,3 or 4 gang switch boxes you should mark what the wires are to be used for in that box. You should mark at the boxes of a three, or more way switch system, where you are running power, and which ones will be switch legs, and then mark all of the rest of the switches within a four or more way switch system, as a 4 way switches. You can do this by marking a small “p”over each switch system yoke {holder of a device} that will be the power end of the system, and a “S/L”over each switch system yoke, that will be going to the luminaire, and a “4w”over each yoke that is in the middle of a four, or more, way switch system. Then mark a big “P”with a red crayon, telling where you will be starting each branch circuit from the panel {Power Run}


When inserting the cables into a switch box, I suggest that you make a pattern of keeping all power ins, and all power outs, inserted “closest to the stud”, then the switch legs, in the order that they will be used, as you have marked previously on the studs. This method of identification will help in the dressing of the boxes, by letting you know what wire is what.

When inserting the cables into a box, you should pull the cable to the box, and grasp it with your thumb, and forefinger, then lay your strippers against the cable, that is beyond where the cable meets the box. You should measure around 6”, 300.14 then cut the cable off, after the 6”tail is allotted. Now strip the sheathing from the insulated wires where the cable met the box. Now insert the wire into the box. The holes in the boxes must be effectively closed, if not in use by a cable 110.12.A and 314.17.A If you are using a steel box 314.17.B or a double gang plastic, or fiber box 314.17.C, then you should clamp the wire at this time. Some plastic, and fiber boxes have screw type cable clamps, and some have automatic cable clamps like Chinese fingers style claps molded into the plastic box. All steel boxes must clamp the cable into place, within the steel box. 314.17.B all double or larger, ganged nonmetallic boxes, must be clamped within the box.314.17.C Single plastic, and single fiber boxes, are exempt from cable clamp requirements. 314.17.C Exception The steel boxes have no such exception. All steel boxes must be grounded using an approved grounding screw, installed in the back of the steel box where a threaded hole is made, by the manufacturer, to fit the green ground screw. 250.126

Examples of boxes wired can be viewed by clicking on each of the following picture icons:


You should dress all of the connections within all boxes, before you insulate, or drywall. If you don’t know what a cable is for, or where it came from, then you can easily back trace it, if the insulation and drywall has not been installed and the framing is still open. Be sure to either crimp or wire nut each connection, including all of the bare grounding wires within the dwelling. 110.14 I require, within my jurisdiction, that all connections, within a box, to be dressed {with wire nut or crimp} upon rough-in inspection. This local requirement will allow me, to easily see, these finished boxes, minus the devices, to be correct, without removing the devices, on the finish. This local requirement will provide us with less of a chance of staining the walls, with finger prints during an inspection. This local requirement will allow me to see more while the walls are still open 90.4 {Authority having jurisdiction} You should wait for the drywall to be hung, and finished before you install the devices, {switches and receptacles}.

You may now ask for a rough-in and power to panel inspection. I allow power to the panel, once the rough-in has been approved, and the service has been built, and the meter base installation has been approved, within my jurisdiction. Some areas require occupancy approval, before, the power is allowed to be permanently connected, by the Utility company. You must not insulate, or cover any electrical work, without prior rough-in inspection approval, from your local inspector’s office.

You should install all of your devices, and all of your luminaire, and all of your equipment, after the walls are finished, and installed have the drywall. You may use the screws of the devices if 12 Awg. and / or the plug in slots if 14 Awg. provided on the devices while installing your luminaire, and devices, if so designed.

Remember that you must have all of the following protected by a ground fault circuit interrupter, all of the receptacles in the bathrooms, 210.8.A.1 all of the receptacles outside, 210.8.A.3 all of the receptacles over the kitchen counter, 210.8.A.6 all of the receptacles in the garage within approximately 8’{readily accessible} of the floor area {with the exception of behind a large appliance such as a refrigerator, freezer, washer, or other large appliance, receptacles with single outlets on a dedicated circuit and not readily accessible}[behind the large appliance] 210.8.A.6 All of the receptacles in unfinished basements must be GFI protected with the same large appliance exception that would apply here also. 210.8.A.5 All receptacles in a crawl area including sump pumps 210.8.A.4 All receptacle within 6’of the wet bar 210.8.A.7

An example of wiring a GFI receptacle that protects other normal looking receptacles on that GFI’s load side can be by clicking on the picture icon to the left.

Remember that the bathroom, kitchen, dining room, nook, pantry, and laundry receptacles must not be mixed with anything else on those circuits. 210.52.B.2 An exception to the above statement is that the kitchen, nook, dining and pantry may be on the same circuits with each other but nothing else is allowed on those small appliance branch circuits. 210.52.B.1

You must provide a 20 amp receptacle adjacent to each bathroom lavatory sink bowl, but not more than 36”from the bowl, and on a 12 Awg., 20 amp circuit. 210.52.D This circuit must be GFI protected. 210.8.B.1 The bathroom circuit may be wired with two different designs at your choice. 210.10.C.3

An example of placing bathroom receptacles in relation to vanity basins can be viewed by clicking on the picture icon to the left.

CHOICE # 1 - If you run a dedicated circuit to each bathroom and keep that dedicated circuit within that certain bathroom, then you may run everything in that one certain bathroom on the same circuit, including a whirlpool bath and that bathroom’s receptacles and that bathroom’s lighting. Remember that the bathroom receptacles on that dedicated bathroom circuit must be GFI protected. You may run everything in that bathroom on the dedicated circuit and then install a GFI receptacle at the end of the circuit to protect the bathroom receptacles only. 210.11.C.3. Exception This is true only if without a whirlpool tub. The whirlpool tub must be GFI protected. 680.71

Another design for the bathroom dedicated 20 amp circuit is to install a GFI breaker in the panel, or install a GFI receptacle in the bathroom on the first device in that circuit to protect everything in that bathroom, then a whirlpool tub may be installed on that circuit because it will be GFI protected. 210.11.C.3. Exception and 680.71

CHOICE # 2 –If you run a dedicated 20 amp bathroom receptacle circuit and install a GFI receptacle on the first receptacle on that dedicated bathroom receptacle circuit, or a GFI breaker in the panel serving that circuit, and only install bathroom receptacles on that dedicated circuit, then you may install all of the bathroom receptacles in all of the bathrooms on that dedicated bathroom receptacle circuit. 210.11.C.3 Remember no other device would be allowed on that bathroom receptacle circuit, not even in the bathrooms, if you use option #2 and run a dedicated bathroom receptacle “only”circuit.

If you decide to install all of the bathroom receptacles in all of the bathrooms on one 20 GFI protected circuit, then anything in those bathrooms must not be on the dedicated bathroom receptacle circuit. If you decide to use option #2 in your wiring design of the dedicated bathroom receptacle circuit, then you may run the lighting in those bathrooms on the receptacle or lighting circuits in the bedrooms or living rooms. 210.11.C.3 and 210.8.B.1

You may run the GFI protected receptacles in the garage, basement, outside, and crawl all on the same circuit. Do not mix those mentioned in the prior sentence with the small appliance branch receptacles in the kitchen, nook dining, or pantry. Do not mix those receptacles mentioned in this paragraph’s first sentence with the bathroom receptacle or laundry receptacles, either. 210.11.C Remember that the sump pump and all other receptacles in the crawl space must also be GFI protected 210.8.A.4

Remember no structure may be occupied until all final inspections have been approved by the “Authority Having Jurisdiction”as follows; Building, Pluming, Electrical Inspectors and the Board of Health and then You must have received a letter of “Occupancy Approval”from the Planning Commission Director’s Office

The 2002 NEC now requires that all branch circuits serving receptacles, light fixtures or smoke detectors or any other type of electrical outlet inside bedrooms must be protected by a new device called an ARC FAULT BREAKER. This includes any circuit serving a bedroomand the requirement is requiring that the entire branch circuit to be ARC FAULT PROTECTED by an arc fault breaker !

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