Minimum 6 8 headroom height clearance for stairway.
Commercial stair tread and riser requirements.
The ibc stair codes are slightly different than the ones set by the irc.
Vertical clearance above any stair tread to any overhead obstruction is at least 6 feet 8 inches 203 cm as measured from the leading edge of the tread.
In summary osha compliant fixed stairs must have.
Width and capacity ibc 1011 2 the number of occupants on each floor will determine the required width of the stairs.
Riser and tread dimensions should be continuously uniform for safety.
International building code for stair treads and risers 1009 3 stair treads and risers.
Maximum 4 1 2 inch handrail projection into stairway width on either side.
The stair tread code requirements are also slightly different with a minimum depth of 11 inches.
1910 25 b 3 stairs have uniform riser heights and tread depths between landings.
In short the width is.
Stair tread depths shall be 11 inches 279 mm minimum.
The tread depth is the distance from the front edge or nosing a tread projection that overhangs the riser below of one step to the front edge or nose of the next step measured horizontally.
Minimum 36 inch clear width for stairway.
Stair riser heights shall be 7 inches 178 mm maximum and 4 inches 102 mm minimum.
Spiral stairs must meet the vertical clearance requirements in paragraph d 3 of this section.
Risers goings and treads dimensions.
The tread depth td is to be 185mm and it should not be more than 30mm shorter than the going g.
Any variation of risers within a flight of stairs should not be more than inch of tolerance.
Ibc stairs code requirements.
This distance must be at least 10 inches.
Commercial stair riser height the code specifies that risers should not be more than 7 inches in height and not less than 4 inches when measured vertically between the nosing of the adjacent tread.
Maximum 12 3 vertical height rise for a flight of stairs.
Headroom ibc 1011 3 riser height and tread depth ibc 1011 5 uniform dimensions ibc 1011 5 4 solid risers ibc.
Therefore let us recap on the residential stair code requirements.
The international building code sets the commercial building code for stairs.
Treads the horizontal stair element you step on that are at least 10 inches in depth and no more than 14 inches.
Risers the vertical element connecting treads that are no less than 6 inches in height and no more than 7 5 inches.
All risers and all goings in the same flight of stairs shall be of uniform dimensions within a tolerance of 5 mm.
