Building Steps Up to Code? First Time Attempting Steps

Question

I recently built a paver patio and the existing porchsteps that were removed during the process no longer fit. I am attempting to research building a new set of steps and my head is spinning with how to build these things in line with code.

I am located in Western New York. I know my rise from the ground to the house threshold is 26 inches. I don't care how long the run is as the steps are running out to a patio.

My initial thought was to buy a 3 step pre-cut stringer from Lowe's as I have never attempted to cut my own before. The stringers are 6.5 inches, which would be perfect as 6.5 * 4 is 26, with the house acting as the fourth step. Then I got to thinking that the additional inch added from the decking board would throw off this math. A 7.5 inch total height step would mean that my last step, into the house, is three inches less than the other steps (factoring in the additional thread inch for each of the three steps on the stringer).

When code references step height, is it referring to the total height between the stringer and the stair thread, or just the height that the stringer is cut to? Would it be acceptable to use the 6.5 inch stringer with the standard 1 inch decking board, for a total of 7.5 inches, meaning that the last "step" into the house would be three inches less than the steps on the stringer?

Thanks, Justin

Answer 1

Building codes are talking about the height difference between each finished step and landing, once all treads and finished floors are installed.

• You are allowed a 3/8-inch difference in rise between the shortest step and tallest step.
• Also, max 3/8-inch difference in tread depth or run
• Because the stair code folks love to say 3/8-inch, the amount of tread overhang should be 3/4-inch to 5/4-inch with up to a 3/8-inch variation between the least and most overhang

If you build a staircase where one step is 3-inches different height than all the other steps, people will trip on that step sometimes, and your homeowner's insurance will put the blame squarely on you.

I bought a book about staircases called Building Stairs by Andy Engel when I was doing a few projects at a home I owned where several staircases were falling down. It was worth the money! Many libraries are full of good home improvement books too; in my area, you can search online before you even go to the physical library to look.

Answer 2

Yes, Jeff Wheeler is correct that the height of risers are measured from their finish tread height. However, handrails are also required if there are 4 risers or more.

Handrails are not required if there are 3 risers or less. (See ICC 1009.15.4)

Handrails are required on one side only. (See ICC 1009.15) It’s customary to have it on the right side descending, but not mandatory.

Handrails are required to be a uniform height between 34” and 38” above the nosing. (See ICC 1012.2)

Make sure you have a minimum of 1 1/2” clearance between the handrail and wall. (See ICC 1012.7)