We will be building a home that sits 5 feet off the ground on a crawl space foundation and are considering a 2 x 6 T&G pine flooring.
Our builder tells us that we will not have to use a subflooring on this floor. Our neighbor’s daughter just moved in a new home constructed the same way. After a week of constant air conditioning, the floor has begun to cup. Air is coming up through the floor as though a window has been opened.
My question is how do I know that I am getting thoroughly dried wood and would a subfloor help this sort of situation?
Replies
I made a lot of money one year by finding a group of homes that something similar was done. Replaced over 90Ksqft of wood flooring, replaced sub-floors.. even had one house that had the joists move over 5" over a 15' span due to improper fastening.
To answer your question... yes.. it is POSSIBLE. BUT, you need to have someone who REALLY knows what they are doing to be able to pull it off. However, the question is... Why?
A sub-floor is cheap (much cheaper than the cost of an installer that can lay the floor correctly)... makes installation of the wood floor 150 times easier... and I could show a monkey with a hammer how to do it! LOL
If the floor ever needed repair... ugggh! The entire floor would have to be replaced (do to the installation technique required to do it right).
My suggestion would be to go with a standard sub-floor construction and install 5/4 wood flooring. Total cost will be about the same (if not cheaper), the wood will be much more stable (easier to dry 5/4 than 8/4), and the floor will have a much better life (let alone the better life that you will have).
I'm ordering about 1700sq feet of Eastern White Pine flooring in the next day or two. Straight edged not T&G.
I'd never put it directly over floor joists which I could have.
The cost of a plywood subfloor will not only strengthen your new pine floor but help asure you of no cupping as long as your wood is sufficiently dry. Buy or rent a moisture meter and check it before installation..
Your new floor should have the same mositure content as your subfloor the day you install it.
I'm not sure which company I'm getting it from....Carlisle or Timberknee.
The people at Timberknee wont let you off the phone when you ask for advice....they go on and on and on, so you may wanna give them a shout.
1 800 720-9823.....Theyre strating to get under my skin for a few reasons but none the less they have good advice and lots of it.
Good luck
and Be well
andy
The secret of Zen in two words is, "Not always so"!
http://CLIFFORDRENOVATIONS.COM
how do I know that I am getting thoroughly dried wood All wood is stamped with a grade stamp ... there have been several quickie articles in FHB and other mags about how to read grade stamps ... one of the marks will be something like KD19 ... which means the wood was kiln dried to 19% moisture content. If you get kiln dried wood, and as long as it has not been soaked by rain during shipment, it will be dry enough.
There may be other problems built into the house, like improper drainage, or excessive soil moisture, or whatever ... more than I know about. The simple addition of a sub-floor may not solve the problem.
Where are you building?
Whenever you are asked if you can do a job, tell'em "Certainly, I can!" Then get busy and find out how to do it. T. Roosevelt
Edited 7/28/2004 8:20 am ET by Ed Hilton
Ed,
I usually agree wiuth you but we have to part company on this one.
KD19 is kiln dried to 19% moisture content on the surface, which mean s that it can still be more like 22+% on the inside. That can be fine for framing materials but even at that, drying studs accounts for most of thje nail pops in sheet rock as they shrink.
Finish trim materials used on the interior need to be dried to more like 9-12% and tested on site with a moisture metere. It will vary according to actuall site conditions.
To the original poster - I would never dream of putting this sort of material over a crawl wqithout planning a vapour bar/draft stop/insulation package to back it up. That info is scetchy in your Q.
We have used flooring like that in log homes with open beamed cielings and you can count on drat coming through, even with nearly equal temp and humidity differential between floors. Given a cool damp crawlspace, the diff is greater and the draft is gauranteed. shrinkage will happen and there will be spaces big enough for insects to crawl through.
Get typical and use a subfloor.
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would never dream of putting this sort of material over a crawl
Only if it were a conditioned space, like the one recommended by Building Science. That condition exists only in a small portion of the U.S. though.
Even then, I'd be leary of skipping the subfloor (and more so of a contractor so recommending). Why? Because what are you putting the tile on, or the carpet? How will it be thresholded?
A solid, 8/4 floor-suitable, floor? It's not (likely) tongue-and-groove, so no blind nailing. Does that mean it gets exposed fasteners? Blind nailed (or blind deck screws) from the crawl space?Occupational hazard of my occupation not being around (sorry Bubba)
The conditioning of the lower space is what I meant as one option with the rest of that sentence - "wqithout planning a vapour bar/draft stop/insulation package to back it up. "
The first poster did say that the 2x6 pine would be T&G, so blind nailing is possible. I tend to doubt it would shrink enough to allow water moccasins in, but it would probably lose a loose knot ir two.
The biggest use I see for that product around here is floors of shops and garages built uplifted on pier foundations and for the secoing floor in cabins. Even in that later usage, there are complaints, the biggest of which is that the sawdust that gets trapped in the joint during construction continues to filter down through the joint onto the TV and dinning room table for years after wards, as the joint gradually opens up.
My FIL has the 2x6 T&G on the floor of his shop and when he is heating it in winter with the wood stove, the draft is always noticeable
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Actually, we agree on this more than you think. I was giving an example of a grade stamp and happened to choose KD19 cuz I was watching channel 19 onthe cable. The original post asked how he could tell if he was getting dry lumber.
And I mentioned that there are other factors involved ... and I know for a fact that my knowledge of damp crawlspaces etc is very minimal, so I wouldn't even try to make an intelligent comment about that. Why do you think I live in the land of concrfete slabs? We aint got no damp crawlspaces here.
Whenever you are asked if you can do a job, tell'em "Certainly, I can!" Then get busy and find out how to do it. T. Roosevelt
Lived in an old house once with 2" wide t&g pine floor on top of joists. I liked it because I could talk to my wife in a normal tone from upstairs while she was doing laundry in the basement. Also, I could look down in quite a few spots and see if she left the lights on down there. I think the centipedes liked it too.
use a subfloor, 3/4" t&g ply is best nail base, and top it w 1x pine (3/4" thick) which will be more stable than 2x material... use a t&g flooring grade material (kiln dried) or plan on using same w/square edges but drill, screw and button along seams to avoid movement, both now while sanding and later w edge raising and making "footcatchers" over 5" in width, glue also but no rosin paper....... the 2x6 t&g pine is made more for utility purposes like roof sheathing on cathedrals w insulation board placed placed over it ...have seen it used for flooring, have sanded it, but always w a lot of movement, twisting, shrinkage, cupping, cracking etc.
use a moisture meter, but try to leave the stock crib stacked/stickered in house at least a week use proper vapor barrier in crawl space couple weeks before bringing material into house don't know your area, but there's some pretty nice SYP and CVG available, manufactured as flooring, both kiln dry and t&g, would better suit your purpose
Thanks to all for your input. I think I am going to have to respectfully disagree with our builder on this one, particularly after Piffin's comments. I have been thinking of the energy efficiency aspect and not what could crawl in between the cracks.
We will be building about 150 feet from a lake. Any subfloor that keeps the moccasins out (and I don't mean shoes) is well worth the money.
NWFA, NOFMA, NMFMA does not permit wood flooring to be installed without a sub floor.
Here are the codes: (NOT BOCA)
3/4" t&g ply nailed and glued is preffered.
3/4" non t&g ply nailed and glued, permitted
3/4" t&g osb screwed and glued, permitted
5/8" t&g ply screwed and glued (minumum requirement.)
End of story.
Ditch