I'm replacing the old carpet from my stairs with engineered hardwood flooring. The stairs are 3ft wide. Since the stairs were very, very squeaky, after removing the carpet I removed the old treads and risers and added 2 extra stringers (unfortunately I could only fit 2x10 stringers). So now I have 4 stringers with 1ft spacing between them. One of the stringers is LVL.
I would love to avoid squeaking in the future, so I was thinking that these 4 stringers would allow me to go with risers that wouldn't touch either of the treads (above or below the riser) - only serve as a backing for the engineered flooring.
Do you see any problems in the risers not supporting the tread above?
Thanks a lot,
Nick

 

How thick will your treads be and what material?

If I follow you, you want to cut the risers a little short so there is a gap between the riser and the tread below and a gap between the riser and the tread above, is that correct?

And the treads and risers will be covered with engineered flooring?

Will you be using the engineered flooring in the adjoining spaces or just on the stairs? Because if it's just on the stairs, I think you'd be better off just using solid hardwood treads and risers, since you've already removed the old ones. Squeaking is pretty easy to avoid with a little planning and care. There are lots of places that can squeak besides the riser/tread joint so you're going to have to use care anyway.

Do you have access to the bottoms of the stringers from underneath the stair?

 

Thanks a lot for such a quick reply.
You understood my question correctly.
I made the new treads out of 2x10 FIR or SPF (whatever was not too twisted - even did some planing to make it flat). I cut the new risers out of 1x8 pine. I started installing everything by installing the risers first - butted up against the treads above, but soon i realized that this creates significant squeak. I must say that I didn't glue and tighten everything - it was just a test install, if I can say so. That's why I started thinking about shortening the risers and use them only as a backing for 1/4" painted poplar. So - the engineering flooring will only end up on top of the treads. The stairs, 3ft wide, are enclosed by two walls and the flooring I want to install is the same as the flooring on the top end of the stairs (second floor).
I understand there many stair components may squeak, but I thought that having 4 stringers 1ft apart and using a lot of glue between the new treads and stringers and using good GRK structural screws may help eliminate the squeak. Just not sure what to do with this riser against the tread rubbing squeak. And of course, this is the perfect time to do it right.
Thanks again,
Nick

 

Construction adhesive and screws will eliminate the squeek. The bottom of each riser should be glued and screwed to the back side of each tread for behind. Risers and treads should also be glued and screwed to each stringer. Once the glue sets up, the stairs will act as one solid unit. Not gluing and fastening the riser to the tread would be a big mistake.

 

XSleeper, thanks a lot.
How about the top of the riser - should it be butted up and glued against the top tread?

 

Yes. All mating surfaces should be glued and screwed.

 

Agree with X. You get extra stiffness from having the risers and treads screwed and glued.

I take it the skirtboards aren't routed? The treads and risers just butt up against them?

Check each tread before you glue and screw it to see if there are any gaps at any of the stringers; if there are the stringer should be shimmed (glue the shim). With four stringers you'll probably have a few gaps.

 

You are right - the skirtboards are not routed and yes - there were some gaps between the treads and the stringers. I filled them the best I could and the treads feel very stable.
I was going to use Titebond Green Subfloor adhesive for this job. Do you have any experience with it? It is water based adhesive that apparently stays somewhat flexible.
I was thinking about using the PL Premium, but it doesn't remain flexible after curing. PL400 would be another option.