Bela Abolfathi, D. S. Aguado, Gabriela Aguilar, Carlos Allende Prieto, Andres Almeida, Tonima Tasnim Ananna, Friedrich Anders, Scott F. Anderson, Brett H. Andrews, Borja Anguiano, Alfonso Aragon-Salamanca, Maria Argudo-Fernandez, Eric Armengaud, Metin Ata, Eric Aubourg, Vladimir Avila-Reese, Carles Badenes, Stephen Bailey, Christophe Balland, Kathleen A. Barger, et al (328)
Stair Stringers (7) Stair stringers form the backbone of a set of stairs. By code, stairs need to be at least 36 wide. Although it's usually possible to get away with just using two stringers, we recommend you add a third one down the middle. This extra stringer will ensure your stairs are exceptionally rigid.
Because of this you should never space your stair stringers more than 16â on center. This means you will need to install a minimum of four stringers on any stairway wider than 36â. Always check the maximum span for your decking material as it applies to stair treads. Some composite materials and lower grade 5/4 wood decking may require you to reduce the stringer spacing to 10â on center. Always read the composite decking installation instructions for stair treads before building your stairs.