Fastening Retrofit Stair Treads
Installers discuss how to fasten replacement oak stair treads to an existing old stringer so as to minimize squeaking. September 5, 2006
Question
I am redoing stair treads, risers and railings for a client. The treads are oak that I am prefinishing before installation in order to keep dust in the house to a minimum. The client mentioned that they would prefer that the treads be fastened with screws to prevent squeaks. However, I would be forced to face screw the treads as there is no access behind the stringers. Then I would be left trying to cover the screws with (prefinished?) plugs. I’m not sure how invisible I could make the plugs. I was going to use construction adhesive on the stringers anyway. I don't work on stairs regularly, but wouldn't construction adhesive plus 15 gauge nails provide a squeak free option. I've heard that firing the nails at opposing angles into the stringer instead of straight in also helps to prevent squeaks. Any help would be much appreciated.
Forum Responses
(Cabinet and Millwork Installation Forum)
From contributor A:
The construction adhesive should hold the treads nicely. Make sure you allow enough to hold the treads in place. 2500# psi adhesive should be good enough.
From contributor B:
I have rebuilt a lot of stairs like this and I found that most of the risers in old stairs were installed first and the thread butted up against the riser. I usually start at the bottom and replace two treads at a time, always leaving the one above off. I screw from the back of the riser in to the thread all the way up the stairs, use lots of liquid nails and shoot some 2" pins at the front. Also if you want to cover the risers in 1/4" oak veneer ply, you might have a little scribing to do but with some liquid nails behind, you will be very surprised at how much this stabilizes your stair. With the new threads and veneered risers it’s like you just installed a new stairs. The best way I think to remove these old treads with the least amount of damage and vibration is to cut them in the centre with a sawzall.
From contributor C:
Construction adhesive and 15 gauge nails should work fine. It's what I use and I haven't had a problem with squeaks at all. Use a thick bead of glue, about 1/2" on the stringers. And glue every wood on wood surface to eliminate squeaks. You could also use trim head screws if you wanted. This makes a larger hole than a 15 gauge nail, but wood filler is all that is needed to fill hole.
From contributor D:
Even though you’re not a full-time stair man, you seem to have a good handle on carpentry. Your customer is paying for your expertise and knowledge. You shouldn't let them tell you how to do it. Explain to them politely that your methods are sound. I'm getting cranky in my old age and it is beginning to show.
From contributor E:
Drill stringers for pocket screws near back of tread. Put tread on with pocket screws and glue. Now put sub-riser on - it's drilled for pocket screws too. Screw it to stringers and tread, and then attach riser face (1/4" material) to sub-riser. This works with a right angle drill or my favorite, a small air ratchet. I don't like putting holes in things that can be seen. The riser face is all you'll have holes in and lots of times they're painted so puttying is okay. No matter how you do it, try to avoid big nail or screw holes in the tread. Having no putty holes makes a much more professional looking job.
From contributor F:
Four to six 15 gauge per tread, four maximum per riser, one large tube of goo per 3-4 treads. If you rabbet your riser so it slips behind the tread you'll have a better joint and if you dado the tread, nose to the riser, it will really be bomb proof.
From contributor G:
One option is to use trim head screws. Fill the holes with color putty. They leave a larger hole than finish nails but I think screws provide a stronger hold and some pulling power.
From contributor H:
Any finish nail will eventually squeak, no matter how much glue you dope it up with. Stairs are the most abused thing in a home. Trim nails are designed for holding up a one pound piece of base, not something that’s going to get pounded on. Glue and screws equal no blues.
From contributor I:
I'm putting 3/8" engineered wood planks (with stair-nose trim) on my stair treads, with painted white risers. I'd prefer to not nail and to only use construction adhesive. I can't seem to find any information if this will hold without the nails. Has anybody put in tongue and groove planks on treads without using nails? Does the stair-nose and planks behind it stay put? What kind of construction adhesive? There are many different kinds, such as heavy duty, sub-floor, sub-floor and decking, etc.
From contributor J:
I would just use the liquid nails and a couple of nails. I think the adhesive is plenty strong enough to hold them. I just shoot a nail or two to keep them from shifting before drying, but if you want the extra nails, shooting at opposing angles does give a better grip, and I would imagine reduces squeaking, but that’s just my way of doing it.
From contributor I:
One of main questions is which kind of liquid nails? On the Heavy Duty Liquid Nails, it says, "Not for flooring". On the SubFloor Liquid Nails, it does not mention that it meets the AFG-01 or D3498 certifications, but perhaps that doesn't matter. I want to use the best and strongest adhesive, since they only vary about $1 each tube. One person recommended "PL1". I found the PL brand. I assume the PL1 is the "Polyurethane Premium Construction Adhesive"? It says, "3 times stronger than ordinary adhesives" and meets the above certifications. Is the Polyurethane better than the Heavy Duty or Sub-floor adhesives? Then I worry that one might be stronger, but bad for high traffic areas, such as stairs. Perhaps the constant foot traffic will cause it to crack or something? I'm sure I'm being too paranoid.
From contributor J:
Sorry for not specifying. I always use what the supplier sends. We have a long relationship - basically I meet her at the house and we go over materials together. I usually just tell her to send flooring adhesive, liquid nails is just my generic term for it. I’d say any heavy duty flooring adhesive that doesn’t directly state that it’s not for hardwood would do. I would suggest you go to a contractor supply warehouse and ask someone there. Around my area we have a place called The Contractor Yard and another called Holston Builders. They supply probably 60-75% of materials on the houses I work in. I would say there would be some very helpful associates at a place like this if there are any in your area. I would guess any construction adhesive that is for flooring would work, but I’d play it safe and call someone who sells it everyday.
The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).
Comment from contributor A:
In regards to proper adhesive for 3-4 tongue groove, gorilla glue is widely used and recommended for stair parts. As for nailing, nail into the tongue. Use nail set if needed for clean shot. Construction adhesive will work fine as well.
Comment from contributor B:
I removed old yellow pine treads and placed a heavy bead of subfloor adhesive on the stringers and riser edge. Then I placed the hardwood tread down and nailed with 2.5" nails. It was very quiet for months and now has started to squeak. I'm sure the adhesive has hardened and shrunk somewhat. For me, I would counter-bore and place flush-plugs over the screw heads, but I'm not unhappy with the squeaks I have.
