I’ll be making poor man’s engineered joists to stiffen an existing bouncy floor and need help selecting glue.
The plan:
Glue and screw 2×4’s to the bottoms of existing 2×10 joists – the 2×4’s will be at right angles to the 2×10’s to form a “T” section.
While the glue is setting, I’ll wedge posts under the joists to raise them 1/8″ or so to provide some pre-tension.
Hopefully this will take away some of the bounce.
The questions:
1) Does someone have a structural grade glue to recommend? (preferably on that’s likely to be stocked at the local lumber yard or paint store)
2) Any thoughts or suggestions about a better way to solve the bouncy floor problem? (this is a first floor with joists accessible from the cellar below; joists are 2×10’s on 14 and 15 ft spans; floor doesn’t sag; but, it bouionces enough to ne annoying.
I’m a babe in the woods on this and any help or comment is appreciated
Replies
A more knowledgeable person will probably ask about solid bridging or similar. To answer your question, there aren't many structural glues. One is a resorcinal product, nasty stuff, has to be mixed (powder & goop), dries a dark maroon. I think the powder is harmful if breathed and I think it may give off formaldehyde until cured. But it's strong stuff.
Your idea would stiffen the floor quite a bit. I would just use liquid nails subfloor. the adhesive used in glulams and TJI's is made not to creep. You can't get it at HD. Since it's not structural I don't think you need to raise them the 1/8" you mentioned. Another reason agaist this is that most glues like liquid nails will creep over time and the static state of your floor will drop that 1/8" anyhow eventually. It'll still stiffen the bounce though. Ssince the bounce is only when someone is walking, there's no steady force to cause a long-term creep.
Darrell Hambley, PE
Look for an APA-01 structural approval. The one recommended to me was PL Premium. It is polyurethane based, dries by absorbing water, it will set faster if you moisten the wood first, and gives you a joint stronger than the wood itself. It is widely available at the big boxes for about $7 and comes in a standard container that fits a caulk gun. Use gloves or it will have to stay until it wears off. Once set flaming gasoline and kryptonite won't shift it.
ditto on the p.l premium the stuff is an incredible adhesive..... bear
PL Premium is the right stuff but I'm only paying $4.10/tube.Excellence is its own reward!
I just used some PL Premium to fasten foam corbels to a house...it worked wonderfully, but I couldn't get it to stop running out of the tube, any tips on that? It's okay, I can fix it!
wrap the tube in duct tape its the expansion, than returning to orignal shape that makes with wrapping tight with duct tape a couple of times keeps the flow to a minimum..........remember a minimum ...........cheers bear also if you take a film cannister 35mm cut a large enough hole so the tip fits in it another step to keep that dreaded mess to a minimum..
Edited 9/21/2002 12:02:19 PM ET by the bear
Drill a hole in the end of your hammer, take some beeswax, and...oops! Wrong threadExcellence is its own reward!
Mecho,
We have had good results by placing a hybrid bridging system between joist. For 2x10 joist cut 9" 2x4 blocks, glue and nail these vertically in a straight line on joist. Rip 3/4" cdx to 9". Cut these to fit between joist and nail and glue to both sides of 2x4. I would probably do 2 runs maybe 3.
KK