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Stair Rise

The code permits the "Stairway Walking Surface" to slope up to 2%. (R311.7.7)

One trick that experienced stair builders know is to slope each tread an 1/8 inch, so that the tread nosing is slightly lower than the back of the tread. Assuming the floors or landings are level, by slightly sloping the treads in a flight of stairs with 13 risers, the total rise will have gained an extra 1-1/2 inches. And the inspectors and users will not notice the slope if the treads are 11".

Most of us on this board know that stair riser height is measured from nosing to nosing. However, in actual practice, the building inspectors commonly measure the riser height from the nosing to the tread below, and never catch the 1/8".
 
The code permits the "Stairway Walking Surface" to slope up to 2%. (R311.7.7)

One trick that experienced stair builders know is to slope each tread an 1/8 inch, so that the tread nosing is slightly lower than the back of the tread. Assuming the floors or landings are level, by slightly sloping the treads in a flight of stairs with 13 risers, the total rise will have gained an extra 1-1/2 inches. And the inspectors and users will not notice the slope if the treads are 11".

Most of us on this board know that stair riser height is measured from nosing to nosing. However, in actual practice, the building inspectors commonly measure the riser height from the nosing to the tread below, and never catch the 1/8".
That is brilliant! I wonder if this would work in the IBC, not just the IRC.

The IBC 202 definition of "tread" is: "The horizontal part of a step".
IBC 202 does not define "horizontal", and Webster's dictionary definition of "horizontal" compares it to the earth's horizon, which curves.

However, if we assume the intent is "horizontal" = "level", then other codes such as CBC 202 have defined "level area" such that it "does not have a slope in any direction that exceeds 1/4" per foot (2.083 percent gradient)". Your 1/8" per foot slope would work in that scenario.
 
The code permits the "Stairway Walking Surface" to slope up to 2%. (R311.7.7)

One trick that experienced stair builders know is to slope each tread an 1/8 inch, so that the tread nosing is slightly lower than the back of the tread. Assuming the floors or landings are level, by slightly sloping the treads in a flight of stairs with 13 risers, the total rise will have gained an extra 1-1/2 inches. And the inspectors and users will not notice the slope if the treads are 11".

Most of us on this board know that stair riser height is measured from nosing to nosing. However, in actual practice, the building inspectors commonly measure the riser height from the nosing to the tread below, and never catch the 1/8".
IG,

Not sure I am understanding your point correctly, but riser height is measured from the tip of the front of each tread to the tip of the tread to the one below and above, nosing to nosing.

Slope or no slope does not get you anywhere on plan review, might on a project where the construction tolerances are given at final and let it fly at final inspection, but a no go on the measurement location.
 
IBC 1011.7.1 Stairway walking surface. The walking surface of treads and landings of a stairways shall not be sloped steeper than one unit vertical in 48 units horizontal (2% slope) in any direction.
 
IBC 1011.7.1 Stairway walking surface. The walking surface of treads and landings of a stairways shall not be sloped steeper than one unit vertical in 48 units horizontal (2% slope) in any direction.
Just because it can be sloped, it does not mean you are allowed to exceed the maximum riser of 7-inches.

One has nothing to do with the other.
 
Just because it can be sloped, it does not mean you are allowed to exceed the maximum riser of 7-inches.

One has nothing to do with the other.
Correction, The pitch of the stair tread does not have anything to do to with the Floor to Floor Rise elevation. Miss typed riser notation for floor to floor elevation.

My Bad
 
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