Minimum 10 inch stair tread depth with nosing or minimum 11 inches with no nosing.
Building basement stairs code.
A prime example is the standard stair width.
Imagine having a 12 high stair in place with a riser height of 9 and a tread depth of 9.
As long as the 3 foot width standard is met you can expand the stairs width as far as you wish.
Maximum 12 3 vertical height rise for a flight of stairs.
To a maximum of 1 in.
Nosings are required to overhang a minimum of in.
The international residential code for one and two family dwellings irc and the international building code ibc address staircase railings.
From the top flight of stairs to the bottom of the stairs each individual riser cannot exceed a difference of 3 8 of an inch.
The nosing on treads believe it or not has a code minimum and maximum of how far the nosing projects over the next stair.
This stair would have 16 treads 9 deep for a total run of 11 3.
Maximum 7 3 4 inch stair riser height.
Irc stair railing code.
There may be local or state building codes for how many inches off center you can space studs such as 16 or 24 inches apart and how much clearance you need for ceilings landings for the bottom of stairs and the height and depth of the steps.
These are two model codes and are offered as suggested guidelines for local code authorities to follow at their discretion.
This becomes an issue when stairs are installed in tight locations under codes that vary greatly from today s current international building code ibc variants.
Staircase code states that stairs must be 3 feet wide or wider.