We are getting ready to install 3 inch wide 3/4 inch thick cherry prefinished flooring over 3/4 chip board glued t/g underlayment.
I posted a thread a long time ago when this job first was mentioned to me as to whether we would need a layer of plywood first. The consensus was yes – now it has become reality.
Here is the question: How should we attach the layer of 1/2 inch plywood? glue and 1/2 x 1 1/2 staples? glue and screws? no glue?
I would like to go glue and air staples. There are no squeaks now and I don’t want to make any. I would appreciate benefiting from your experiences on this. thanks
Replies
I'm not a flooring guy, but generally constructuion adhesive reduces squeeks. I think i might locate the joists on the perimeter before laying th plywood and shoot the ply down with ring shank 8d nails into the joists as well. I tend to go the bomb proof method so a few staples in between wouldn't hurt either. good luck.
"it aint the work I mind,
It's the feeling of falling further behind."
Bozini Latini
If you subfloor is a product like Advantech, you really don't need to add any plywood. If you feel you do, I'd screw it, no glue.
Beat it to fit / Paint it to match
Fonzie, please clarify, you have 3/4" T&G "chipboard" glued and ? (screwed or nailed?) already installed as subflooring, right? If so you don't need the 1/2" underlayment, just lay install your cherry flooring to the subflooring
What is the 3/4" subfloor attached to?
Geoff
The last time I ran this several (as I remember) said you better put plywood on that to make sure and hold the nails. It's not Advantec - or whatever the fancy stuff is. The couple both manage lumberyards and have heard a lot of talk both ways on this issue. So about a year ago I ran this on BT and there was both views, but enough that had evidently had bad experiences that I decided plywood is the way to go. I'm wanting to take the most sensible and sure route which seems to me the plywood route. I don't know where all those guys are that were saying don't do it without the plywood layer.
Can you possibly post a link to that thread?
Can you possibly post a link to that thread?(I can't think of any word that's unique enough to narrow the search sorry)
Fonzie,
Any chipped board (partical board, whatever) will not not hold flooring nails acceptably. The mechanics are relatively simple once you understand that solid wood shrinks and swells depending on how much moisture is in it. That moisture comes from humidity or lack of it during the heating season..
Partical board, osb, chip board, wafer board, whatever you have is basically encased in glue which usually seals off thewood fibers from reacting to those moisture levels. If it's soaked under water all bets are off. You don't intend to soak the floor do you?<G>
Plywood will swell and shrink just like solid wood will and it can accomodate that relative wood movement easaier than partical board can.
Now as to gluing, it really depends, how long do you intend to remain in the house?
If it's a realtively short time, go ahead and glue if you want to.. the glue probably won't dry out enough for failure in a short time and you won't have to put up with the annoying crack, crack, crack, as you walk over glued hardwood flooring where the glue has dried up and failed..
This is a case of where a belt and suspenders isn't a good thing..
I'm not going to glue the hardwood flooring just the plywood laid over the 3/4 chipboard. The flooring gets put down with "power cleats".
we all knew that...I'm not sure if frenchy was talking about subfloor or the hardwood, hard to tell the way he worded it. in either case, I still want to know what kinda glue he is talking about.
alrightythen,
Hardwood flooring, it's standard practice to glue subflooring and I have no issue with it,, the surface area is large enough and plywood is stable enough that the wood movement present in hardwood flooring which is the cause of glue failure under hardwood flooring won't happen under the plywood..
Wont a layer of felt between the cherry and the ply help avoid the squeks?? Glueing the ply to the sub sounds like a good idea
"If it's a realtively short time, go ahead and glue if you want to.. the glue probably won't dry out enough for failure in a short time and you won't have to put up with the annoying crack, crack, crack, as you walk over glued hardwood flooring where the glue has dried up and failed.. "
what kinda glue you talking about?
You said that :
"I would like to go glue and air staples. There are no squeaks now and I don't want to make any. I would appreciate benefiting from your experiences on this. thanks."
I think that is a very good solution, in fact, it is my preferred way to install pre-finished strip hardwood flooring over chip board. I have installed it over chip board that is specifically listed as being OK for direct hardwood installation, but I've never felt good about it. You can use either narrow or medium crown staples, just so they are 1 and 1/4 or 1 and 1/2 inches long. Set your stapler to set them flush with with top of the ply.
I like to use PL premium urethane construction adhesive, 1/4 to 3/8 inch wide stripe every 12 inches on center, and make sure the seams of the plywood don't match the seams of the chip board. I staple every 4 to 6 inches on the perimeter of the ply, and every 8 to 12 inches inside the sheets. I try to put my weight where I am stapling so the ply is tight and in contact with the adhesive.
I'm one of the guys that advocated a layer of plywood.
I would glue and fasten the plywood. I pefer nails and screws over staples. I don't know that staples are inferior....I just haven't been sold on them as yet.
I would screw off the existing subfloor. Using PL adhesive to reduce squeaking I nail plywood through to joists and add screws in the "field".
You're not a forum cop, are you?
Just got a chance to scan the thread and I'm sure you have probably gone to this site but they have some helpful info.http://www.nofma.org/Home/tabid/36/Default.aspx Look under publications, you can download instructions, etc. as PDF's free. They recently redisigned the web site; the old site was much much better.I have been preparing to install Brazilian Cherry over a concrete slab and because of potential moisture issues, opted for an engineered product over the solid flooring.
Edited 1/24/2007 10:11 am ET by bobo66