Why are my new wooden treads narrower than the original carpeted treads?

Question

We just had carpeting removed from our basement stairs and oak treads put in. The length of the oak treads put in is now shorter, and only measuring at 9.5" on the treads. Our contractor is telling us that 9.5" is code for our city and we are fine, but our other stairs are 10 3/4" for tread depth and this is a noticeable difference when walking on them (my whole foot can barely fit on the 9.5" stairs).

The treads overhang the riser by about an inch. I never measured the treads before, but underneath our carpeting we had very basic "carpenter stairs" and I never noticed them being narrow to walk on, and now I do. The house was built in 1989.

What should I do? The contractor is not fully paid yet.

Answer 1

The house was built when the code allowed a 9" run with a minimum of a 3/4" overhang (9 3/4" tread) and I believe and a maximum overhang of 1 1/4" (10 1/4" total tread depth). Your stairs are presumably original to the house and for the contractor who reworked the treads, I am sure would have not gone through the trouble of shortening all the treads. The code measures the treads from face of riser to face of the next riser, or stair nose to stair nose, the same thing just taken from different reference points.

In order for the contractor to shorten all the treads would require a lot more work on his part than simply replacing the treads with oak.

11-25 Edit

I thought this may clarify the extra work that would be needed to change all treads to a smaller size. I am either missing something or the carpenter spent a lot of time to do a totally unnecessary thing.

Answer 2

OP states all the other stairs in the house have a tread depth of 10.75" but after the contractor redid the basement stairs they have only 9.5" of tread depth. Pics in comment by OP are consistent with tread depth 9.0" (not 9.5") and rise 7.5". OP should edit the question to put the link to the pics there. (Can leave the link in the comment, and just add link to the question.)

OP reports the basement stairs walk differently after the work, are cramped. OP thinks the contractor left the old risers in place and added new risers by fastening them to the faces of the old risers. The may be the accepted way to add hardwood treads and risers to a stairs which were originally built for carpet. The original 2x lumber is left in place and treated as subflooring for treads and for risers.

The original stairs had a significant overhang of the treads past the original risers which might have been 1" or a little more and would have been exaggerated due to having carpet over nearly sharp 90 deg edges. On the new treads the nosing is more rounded in cross section, is slick hardwood, and may not protrude as far. This would shorten the tread depth.

It is hard to understand how these two factors could account for the tread depth being reduced from an original 10.75" to the current 9.5".

What to do now? I would not accept a modification to stairs that presented a safely hazard that was not present in the original construction.

It could be that in some parts of the US it was common to have basement stairs that were inferior to the stairs in the regular living space, but IMHO this is not acceptable in the present day. In fine homes in the UK and maybe in the US I believe there were servant's stairs that were steeper (higher rise and shorter run) and with shorter treads than the owner's stairs in the house.

If the OP does not have measurements of rise, run and tread depth of the original stairs with carpet removed, then she should ask the contractor if he measured that and has the measurements. In any case, the contractor should have informed the homeowner that the redo as planned would reduce the tread depth and make the stairs harder to use than the original construction. Even if 9.5" is the allowed minimum, it is not as convenient as 10.5" and is significantly different from all the other stairs in the house.

There is a standard that the rise + run = 17" to 18". But it seems that in practice in using this standard the tread depth is used in place of run. This suggests that perhaps the stairs could be made more like the rest of the stairs in the house by extending the nosing to the maximum allowed. But could this be done without removing the treads?

Answer 3

What should I do?

Call your city building inspector, express your concern and ask her to come inspect your carpenter's work.

You may get an answer over the phone of the exact measurements that will meet code, or she may schedule a time to stop by and check for herself. Even if this inspection costs you some money, you'll sleep better knowing one way or the other, whether or not this meets code.

NB: I can't imagine that replacing carpet with hardwood on stairs would require a permit, so there shouldn't be any worry here. If it does require a permit where you live (and the contractor didn't pull one), then this will tell you a lot about your choice of contractors and you should maybe ask the inspector to cast a careful eye over all the work done by the contractor...

These stairs no longer match other stairs in the house.

That's a matter of what was specified in your contract with your carpenter and that's not something we can deal with here. If it was spec'd that there should be no changes in the rise/run/feel of the stairs, then the contractor is in breach. If it wasn't specified, then there's not much you can do other than ask for a change order, get a quote, and decide whether or not to pay for it.