Increase Stair Tread Overhang for Safety?
The stairs in our house have narrow treads (below code min of 10″ at 8.5″), however the nose overhang is already nearly code maximum (almost 1.25″). A builder is recommending replacing the treads with ones 9.5″ wide and adding trim for support (and to make it look nicer). This would give us an inch more tread, but make the overhang ~2.25″. Aside from any code questions, does that sound like a good idea? It seems like it would make it easier not to fall down the stairs while maybe making it easier to trip and fall up the stairs. That sounds like a good trade, but maybe not if tripping becomes common. The goal here is to make the stairs safer, but they could also use new treads regardless.
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Replies
Paul,
The amount of tread available to step on when descending depends on the run of the stair, and will remain exactly the same no matter how much you extend the nosing. You will have more tread to step on g0ing up, but there is a maximum allowed because it becomes a tripping hazard if it overhangs your foot too far.
I'd avoid avoid adding more non-code elements to a stair that as already non-conforming.
Unfortunately there is no easy way to make a stair that is too steep safer. The problem is always going down the stairs and nosing length won't change this.
This is usually a problem with basement stairs in older homes, the only way is to take it out and rebuild the rise and run to code. This does sometimes mean adding a winder or re-framing to make room for the longer run. Not an easy fix but if you will be using the stair all the time but it is worth it.
Doesn't sound like much run difference, but that bit of reduced run you have really does make it annoying to walk down the stairs and much easier to slip.
Sadly there is no magic answer to fit a safe stair in a small space.
Consider expanding the foot print of the staircase. It will not be cheap or easy and the loss of floor space upstairs very painful.
Walta
Obviously you should extend the nosing on only half the step, alternating which half with each step. That will help so long as people approach the stairs with the correct foot.
(I'm joking that you should do that, but it would extend the perceived run to a down stepper.)
The issue as mentioned by Malcolm and akos is that your foot is largely in front of your leg, so the 'pocket' created by the overhang is only useful when your toes are facing into it (on ascent).
Ha, that's kind of brilliant. I'm almost tempted to try it. You know, does the code actually actually have verbiage to prevent this? I'd like to see the look on the inspector's face.
Thanks all. I had given the stairs some thought a few years ago and determined there was nothing to be done (short of lengthening the run), but when the suggestion came I got hopeful that maybe I'd missed something. But yes, of course the tread exposure going down doesn't change. And unfortunately (or maybe fortunately since it makes the decision easy) the top landing has no room to give and to extend the stairs at the bottom would just make walking through the house awkward, so I think there is nothing to be done. Well, we still have a hand rail to put in so at least that will help....
What about adding a riser that is on an angle? Gives you a smaller nosing overhang, but gives you the full (or almost full) tread depth. Might look kind of silly, and may not actually prevent the tripping hazard, but throwing it out there.