There are many choices still to be made once you've decided on vinyl siding for your building project. Depending on the diameter and layout of what you are building the siding comes in many different sizes. Not only does the length very, but the number of shingles per piece can vary. The size of the shingles can vary from 3 to 8 inches in length. And there can be between 1-3 shingles on each piece of siding. For large structures like warehouses you'd want large sheets with long shingles. If you have a house that has many turns and corners you may decide to go with pieces that are smaller with fewer shingles, this will give you a more professional finish.
There are different ways that the vinyl interlocks with each other depending on the type and brand. For most structures a variety of sizes will be used to help give a smooth and contiguous look. Using a greater number of the large pieces will be better off for longer wear. When you use the larger pieces there are fewer seams and vulnerable points where water and debris can seep in. Over time if water is getting underneath the siding it could break down the material and cause mildew to form. On the flip side of this using the smaller pieces in tight fitting spaces is the better way to go. You will want a nice secure fit in the small crevices to give a polished look as well as maintaining a tight seal. Having these different sizes makes cutting the siding less necessary and ultimately makes the job go faster. You will see the seams, but your final project shouldn't have any gaps or rough edges.