We’re renovating a weekend home that sits about 150 from a lake in the Northeast (CT). We have speced a wide plank oak floor (about 7 1/2″) for the ground floor. So far we have had three flooring contractors turn down the job because they are concerned that the floors will cup due to moisture based on the proximity to the lake. We have extensively rebuilt the foundation, dug out and poured new slabs w vapor barriers, new drainage, etc so we are confident that the basement and crawl spaces will be as dry as they can, even to the point of installing full time dehumidification in the spaces below grade.
The house will be used sporadically, sometimes closed for a week or more during the hot months, and with the heat turned down to minimal levels during the fall/winter months, but never closed and unheated. The house will have central AC but in practical use, we often leave windows open and only use the AC during the hottest days.
Are these contractors being too conservative or are we inviting disaster? Are there installation methods that will minimize their concerns? I had a suggestion of skip tar paper and glue down as well as nail down the planks?
Any thoughts??
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Doug,
Are the boards cupped now? how old are the boards? How are they fastened? finally what is the finish now on the floor?
Without knowing the facts, if the boards are flat now and uncupped a minor surfacing won't affect the boards.. so yes they are being too conservative, but perhaps they asen't.. I've seen some floor guys who sand the wood to the point of heating them up and then put a finish on the top that promotes cupping..
Sorry i wasn't clear. Floors have been ripped out in places through to the joists so new underlayment and brand new flooring to be installed.
Let me understand you a little better please, you are ging to nail boards that wide directly to the joists? You aren't using subflooring?
I don't think I would.. the span is too great for 3/4 inch thick boards.. now if it's going on top of 2/4 plywood or car siding or some other flooring that's another story.
Yo can use wide plank flooring without fear of cupping if you take the proper precautions.
Wood wants to move and some woods like Maple want to move a lot! you'll need to accomidate that movement.. there are plenty of ways to do so and they will all produce a nice floor without cupping but it's not just a matter of banging in a few nails like you do with 2 inch flooring..
If you'd like I'll be glad to discuss the details with you.. (yes a patient do-it-yourselfer can do it if they do it correctly)
Boards will not be nailed directly to the joists. We are installing 3/4 ply as a subfloor, then the wide oak planking. The concerns is that the planking only gets edge nailed and the width may cause some cupping. If it is installed in the next few weeks as planned, when humidity levels are at their midpoint, and finished with good quality poly, why are these installers balking?
Please share your tricks
Doug,
edge nailing won't work. the installers are correct about that. Wide plank needs to be secured in the middle in several places.. Often that is achieved with the use of old fashioned cut nails and leaving them exposed. I don't like that look since I feel that it detracts from the appearance of the wood..Alternative appraoch would be to fasten them from underneath as I intend to do.. What is done is slightly oversized holes are predrilled into the subflooring and then screws are used to fasten the planks from below. The oversized holes allow the planks to move relative to the subflooring and thus preventing the wood from splitting.. Best done whenever humidity is at it's absolute peak, Typically in June around here. Then the boards can be put together as tightly as possible without fear that further swelling will cause the boards to cup. As they dry out and shrink there will be significant gaps but to me that's part of the charm of wide plank flooring..
The good news about this approach is that you can close up the edge gaps by a significant amount since swelling will take place between boards rather than at the parameter as is the case with strip flooring..
I favor rosin paper rather than tar paper for two reasons, first you want the wood to move smoothly rather than in the creaky jerks that are typical of Tar paper and second I dislike the oder that Tar paper gives off.. If you need to control vapor do so after the floor is in and then you can put a heavy poly vapor barrier on the joists.
Do you really notice the smell of tarpaper after the floor is down. Would doubling up on the rosin paper act in anyway as a partial vapour barrier.
Wow,
That seems incredibly labor intensive (fastening from underneath) particularly in my in my case as much of the floor is over a crawl space with 2-3 foot clearance, but seems like it would do the job. Are you also edge nailing?
Doug, there is a lot of previous posts on this topic that I researched recently. I am planning on installing 6 7/8" heart pine next month. Another method (that is also time consuming) is to screw the boards down and plug them. One screw hole should be slightly oversized to allow for movement. My neighbour glued down a wide plank floor and the floor has cracked. You have to allow for movement, because you can't prevent it.
Doug,
my method of fastening is incredibly labor intensive.. Since I'm the labor and I actually enjoy this kind of work, there isn't any reason for me not to..
However you can also counterbore the screw holes from the top, install the screws from the top and then put wood plugs (cut them from the scraps of planks and they will match the wood and with careful alignment of the grain disappear almost completely).
No rosin paper is not nor will it ever be a vapor barrier. As for can you smell tar paper, on a warm day with the sun shining on the floor you will be able to smell that tar paper (oops, sorry!,.... building felt) for years afterwards..
It's debateable if the oder reaches offensive levels after a few years but that's one of those things that is easy to fixate on.
Installers like to use building felt (tar paper) but I have noticed that their own homes all seem to have rosin paper, ;-)
Now you can have some fun with this if you want to.. I mean use contrasting wood for your plugs or put a interesting pattern of plugs in or something..
Edited 4/17/2005 2:42 pm ET by frenchy
Their concern is justified. But not reason enough to avoid it. If it's plain sawn oak there'll be a lot of movement. Can you get quarter sawn? Takes a big tree to yield quarter sawn that wide, but that's the only way I'd attempt it.
It's the change of humidity that causes the problem. Turn on the AC and rh drops like a rock. Even going from a very dry winter rh to high summer rh will make plain sawn move substantially, buckling if it was laid too dry, huge winter gaps if it was laid too wet. Quarter sawn avoids these problems.
If you spend a little time with Hoadley's "Understanding Wood" (a Taunton book) you can predict how much movement, based on changes in rh and grain orientation.
PAHS Designer/Builder- Bury it!
I like the idea of quarter sawn material. However, this will only minimize movement. You cannot eliminate movement. I am not sure it would be a good idea to go with composite material. In wide boards, they are actually floating floors. Room size will play a significant role.
DO NOT glue down. These boards will move. Glue will transfer the stress to where you don't want/ expect it.
Tar paper throughout.
Screws, yes. 2 -3 across each board.
One comprimise might be to use boards of varying widths.
Wood floors this wide are best installed in the spring and fall when the humidty and temp are at an average. Use a moisture meter regardless.
Be sure to get someone who installs thes floors on a reg basis. This not a job for first-timers.
F
points about RH and wood movement are a consideration - cupping is caused by low humidity across the top of the board and high humidity underneath - sounds like you have addressed the high humidity underneath (dirt crawl spaces are the worst) - -
one thing you can do, if the material allows it, is to put the 'heart side up' - - observe the grain orientation at the end of the board and put the side that was closest to the heart of the tree to the top - - then the nature of wood movement is for the center of the board to raise, which is not as signifigant as the edges standing proud - - if it's commercial material, I'd guess that you do not have a choice, tho...
I won't get into arguemnts over all the variouys ways and manners of doing this, but it can be done. Still, I wouldn't hold it against any installer who sidesteps such a job either. it is chancy at the best. Here is my most successfull one-
I bought the wood, milled with relief dados ion a T&G flooring pattern 11-1/4:" wide pine two or three months early.
I sstickered it in the basement with a dehumidifier for a few weeks, then used shellac to seal all sides and restickered uit until tim e to install.
Unfortunately, the install happened about the worst time of year, late June or in july. i'm sure they abosrbed some in out humid coastal August.
We edge nailed over resin papre to install, and then added two rose head cut nails at each joists- about one inch to an inch and a half from the edge.
We used cardboard and drop clothes for protection while we finished the rest of the trim, then the flooring guy sanded and stained and polyed the floors. Some were over radiant heat, and some were not. One or two rooms were glued instead of free on resin paper.
All have behaved well with no cupping. Al have shrunk up to an eighth of an inch, but many only a barely noticeable sisteenth.
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as you know Paul....I experimented in my house...upstairs is not glued...just rose head nails and red rosin paper.
Downstairs IS glued with PL Premium....Its been four seasons since and I see no differance yet.
Keeping my fingers crossed.Some planks are as wide as 19" and its pine.I'll let ya know.But I do hate that tung oil crap....Poly is the way to go if ya ask me.Your floors look great by the way and my camera is busted so....
My floors (nailing schedule) ain't even close to yours....lol.
Be well bro
a...The secret of Zen in two words is, "Not always so"!
When we meet, we say, Namaste'..it means..
I honor the place in you where the entire universe resides,
I honor the place in you of love, of light, of truth, of peace.
I honor the place within you where if you are in that place in you
and I am in that place in me, there is only one of us.
One of these days, we'll walk on each other's floors
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
One of these days, we'll walk on each other's floors>>>>>>>>My guess is that's true.
Hopefully in this lifetime
Be well my brotherman
a...The secret of Zen in two words is, "Not always so"!
When we meet, we say, Namaste'..it means..
I honor the place in you where the entire universe resides,
I honor the place in you of love, of light, of truth, of peace.
I honor the place within you where if you are in that place in you
and I am in that place in me, there is only one of us.
photos
Welcome to the
Taunton University of Knowledge FHB Campus at Breaktime.
where ...
Excellence is its own reward!