Adding solid risers to your stairs will not change the results of the Stair Calculator, so long as you properly attach the risers before you add the treads, as shown in the Stairs with Solid Risers and 2x12 Treads diagram below.
How to determine the width of the stairs? Depending on the use and local regulations, a minimum width of 80 cm is recommended for stairs in single-family homes, and greater than 1.00 meters in public buildings, taking into consideration the tentative number of people who will use it. As a...