I am doing my own treads and risers in my house. The staircase has temporary treads and we do not have flooring yet. Without the temporary treads, the distance from the floor to the top of the riser is 7.5 inches. My flooring will be 12mm, which is almost half an inch i think. The tread is 1 inch thick. So that puts my distance from the floor to the top of the riser at 8 inches, isn’t code 7.75 max? This is only an issue on the first step, all the other steps will measure 7.5. am i missing something? Are my numbers off?
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Code is 7 3/4 max where I’m from. Also, you can not very more than 3/8” for all the risers.
To calculate risers you measure from finish floor to finish floor, so you need to know what type of finish before you cut the stringers. When you cut the stringers you have to remove the thickness of the tread off of the first riser. So if carpeted stairs with a 2x12 for tread, you remove 1 1/2”. For solid finished oak on stringers 1 1/4” (the assumption that oak is 1 1/4”). If you were to have 2x12 tread with a finish tread on top you remove the thickness of 1x12 tread and the finish tread.
Your numbers are right. What the greatest code-legal rise is depends on your location. Many northeastern states allow riser heights up to 8 1/4 in., but the rest of the country is less.
A 7 1/2 in. plumb cut on the bottom step seems wrong. Did you deduct the thickness of the tread from your layout when you cut the stringers?
Thanks for the responses. The issue is the stairs are already installed, we are just supposed to remove the temporary treads and put on our own. I'm in NC and i don't believe we are allowed over 7 3/4. Ughh
Here is the first step with temporary tread.
Assuming your code is 2006 IRC or newer. You cannot exceed 7 3/4” riser height. Also, the difference from tallest riser to shortest riser can not exceed 3/8”. So if tallest riser is 7 3/4” cannot have any riser less than 7 3/8”. I’ve had to repair stairs before to get them to meet code. It is a pain, but can be done w/out replacing stringers. It involves shimming tops of stringers to increase riser height or cutting stringer in place to make shorter riser or combo of both. Remember you can vary 3/8” of an inch, so that helps a lot. It’s hard to tell the specifics of yours without knowing finish floor to finish floor heights. From the pic it looks like the finish floor has not been installed, so you might loose some height on the first step once that is installed. You could possibly remove the amount needed from the first riser and remove 1/8” less from the first riser measurement progressively on each riser as you go up. After 3 steps it may be enough to blend into the following steps. Also, if you place a small level on the tread and find its pitching up on the nosing side of tread you can cut it level or sneak a little lower than level to make up the difference. Hard to tell w/out being there.
Thank you. That may be what we have to do- trim them or shim them to make it pass.
What's the finished floor below the bottom step going to be? Can you make up the riser height with that?
Keep in mind the rules are there to make the stairs safer, to reduce falls. So you want the rises to be near-identical if possible rather than to just barely meet the rules. Worth a few more minutes now because you'll never fix it later.
Remember to think this through as whatever you do starting at the bottom ends up affecting the next tread up. That can accumulate real fast and really mess up top.
What's your top tread looking like? If the bottom of the stringer didn't get cut to allow for the tread thickness, it's likely your top riser is going to end up too short.
Check out the Fine Homebuilding issue 168. They describe what I’m suggesting in better detail. I’m just a dumb carpenter/builder, so may not be explaining it well. There are a lot of things that effect what you can do for the repair and you may find that making up the difference in height is so great that new stringers will need to be cut. Remember you always cut the tread width off the bottom riser (concrete stair forms are only exception). I don’t believe that happened. If you provide finish floor to finish floor height along with tread thickness I or someone can tell you what you need to cut the new stringers at. Hopefully, you can do as issue 168 suggest and be done with it.