Hello. I’m building a house of my own design, and today I realized that I’m not at all sure about length of fastener to use to attach subfloor to joists. (I know about adhesive, etc.)
My engineer spec’d 10d ring shank or screws. I’m betting screws will be better… but I will be putting a DIY sandwich for radiant floor heat over the first 3/4″ layer of subfloor… so maybe nails are ok?
Tell me what you think, and in either case, what length. Aren’t 8d more common for this?
Thanks for yout help.
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Replies
8cc is what I have always used along with gluing the pwood down.
sully
BDohrn
I used 3 & 1/2 inch 12 penny nails on my subfloor (along with PL premiuem)
Oh, did I mention my sub floor is made of 2x12's (actaul not demensional) ?
12D nails are usually 3 1/4". I would use #8 ring shank in a nail gun.
8 or 10d ring or spiral plated..
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Forget the primal scream, just ROAR!!!
8d ring shanks!
I also vote for 8 ring shank and be sure they are not over driven.
I use 8D galvy ring shanks out of the nail gun and tap with a hammer to snug them into the glue.
We just discovered this new subfloor adhesive that is way better than PL premium. It's called Bostick and Stock building supply sells it. Instead of having paint thinner in it it works on the same principle as gorilla glue, it's activated by moisture, so you can use it in the rain and it doesn't shrink as it dries. Plus it's not smelly and it's not flammable and it gets you green points if you play by NAHB green or LEED rules. Workable to well below zero too. I won't be using anything else anymore.
I have no financial or otherwise connection to this company, just like their product.
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"You cannot work hard enough to make up for a sloppy estimate."
The guys who have gotten neurotic about squeaks use 1¼"x#8 flooring screws and PL premium for a ¾" OSB subfloor sitting on TJI's.
The rest use 2-3/8" air nails (clipped or FRH, depending on what kind of guns they run). The few hand nailers left generally use 2½" ring-shank. They may or may not use glue as well; depends on the crew.
Dinosaur
How now, Mighty Sauron, that thou art not brought
low by this? For thine evil pales before that which
foolish men call Justice....
1.25" screws are a tad short aren't they...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!Forget the primal scream, just ROAR!!!
Typo. I meant to write 1¾". Thanks fer catching that.
I actually prefer 2" but I'm an overachiever....
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
Weyerhaeuser says not to use polyurethane glue for subfloor. They spec ASTM D3498 (AFG-01) min dry shear 350 psi. Looking at a tube of PL it says meets or exceeds APA AFG-01 and ASTM 3498 and HUD UM60a.
Weyerhaeuser says not to use polyurethane glue for subfloor. They spec ASTM D3498 (AFG-01) min dry shear 350 psi. Looking at a tube of PL it says meets or exceeds APA AFG-01 and ASTM 3498 and HUD UM60a.
It would appear that Weyerhauser and Lepage don't agree on this. I would be curious to know what Big W's problem is with polyurethane glue.
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
they're not owners, all or in part, of PL....
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!Forget the primal scream, just ROAR!!!
I knew that. I was just wondering what the official excuse was.
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
Twenty five years ago we used Liquid Nails and 8p nail gun. I'm still living in one of the houses we built and the floors have a number of squeaks. I used to know a framer that glued floors down with Elmers Glue. I've always wondered how that worked out, anyone ever hear of this? I'm planning on building one more home to live in and I'm leaning towards a slab. Mostly because I like the appearance of the low roof line.
I looked for a 10D ringshank but couldn't find any to nail down the 1 1/8" warmboard because I was worried that 8d's were a little short.No 10D to be found but the 8D x .148 were fine. Used GE 400 and it is almost impossible to remove.So far so good...
Used PL and plain old spiral 8D gun nails, same as for the sheathing. Just like my brother taught me 25 years ago- except we weren't using guns in those days. Subfloor is 5/8" T&G ply. It spent lots of time in the weather (did the whole job myself so it took a while to get it dried in!), and it stained a bit but there was very little swelling and no disbonding.
Had to take up a piece of subfloor later to plane out the subfloor of my addition relative to the (crooked) existing house- one joist was just a little too proud for my liking. Man, that PL grabs! Took a chisel to get that plywood off the joists. If you use PL and ring shank nails, the only squeaks you're going to get are from bad bridging or blocking between joists etc.- can't imagine the subfloor ever working loose from the joists!
You can reduce the height of a framed floor to the same height as a slab by notching the top of your foundation wall to let in the floor joists. Last time I did it for a handicapped client whose racing wheelchair was very sensitive to the small variations in level common in slabs. I let in a treated 2x and used hangers for the I joists. More often it's done by notching the concrete back 4" accommodate a 2"x4" sill plate.
I live on a slab and while it doesn't bother me, my wife has begun to mutter about a more cushioned floor surface as we get older.
All you need is glue and 2-1/2" ring shank nails.
Unless it is a small area or you are in love with screws, I'd go for nails, 8d or 10d rings, I've used both depending on job/engineer specs.
Biggest advantage of screws is their resistance to pulling out and rubbing, which is where your glue and ring shank come into play.
Thanks everyone!
I have been screwing my sub floors down for many years now, also use PL and deck mate 2 1/2" screws.