How far apart should stair stringers be?

How far apart should stair stringers be?

Cut stringers can be spaced no more than 18 inches on center, so a 3-foot-wide staircase needs three stringers, and a set of slightly wider stairs (say 3 feet 6 inches) needs four stringers. The maximum 18-inch spacing presumes treads of 5/4-inch wood decking or 2-by stock.

What size lumber is used for stair stringers?

Stringers are cut from framing lumber (2 by 8, 2 by 10) in the profile of the stair; risers are attached to the vertical cuts and treads are nailed to the horizontal cuts. Stringers cut to the proper dimensions are essential for building a solid set of stairs.

How do I support a stair stringer?

The angle is based on the amount of space available, but is commonly determined by the rise and run of a stair. With a 7 inch riser and an 11 inch tread (this is usually a minimum) you get an angle of arctan(7/11) or 32 degrees. Most carpenters will simply use a framing square to figure this rather than doing trig.