I get this question a lot, how many stringers should I use when building a set of stairs? These questions are really easy to answer and with a bit of common sense and the ability to read a tape measure effectively, you should be able to give a clear explanation that will give you the answers you are looking for.

It is common in the construction industry for ceiling joists and floor joists to be 16 inches on center and we can also use this measurement when building a new set of stairs and calculate how many stringers we need to use.

If you have a 48-inch-wide stair and you divide your 16-inch center measurement into 48-inches, you’ll find that you need to use that for the stair stringers. If your stair is between 30 and 36 inches, you will need three stair stringers.

The number of stair stringers you actually need will also be determined by the thickness of the stair treads. If you are going to use a 4 x 12 stair tread, you will most likely only need one stair stringer at each end of the stairs, if the stair is less than 40 inches wide.

If you are using 2 x 12 treads, you can space the stringers 24 inches on center. The thickness of your stair tread will affect how many stair stringers you actually need, but you can’t go wrong with the original measurement of 16 inches on center unless you’re going to use treads that are less than 1 inch thick. .

Always check with a building professional first, before building your stair to verify the number of stair stringers you will actually need. This article is only meant to give someone a general idea, but it cannot be used in all situations effectively.