Hey all.
Quick subfloor issue here. I am updating our 1920’s bungalow and am replacing a floor in an upstairs bedroom. I removed old vinyl and ply. Subfloor is random width boards running perpendicular, not diagonal, to the joists (@16 oc). It is in generally good condition, with a few splits in one board.
I plan to install 3/4″ T&G 2 1/2″ pine floor. Do I need to replace the existing subfloor? Just the split board? Other suggestions?
Thanks in advance for your help.
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Replies
I just ripped out the subfloor in a job and replaced it with 3/4" plywood for this very reason. (I'm assuming that your subfloor and finish floor are running parallel.) I ripped out the old ship lap 4" boards because I was worried about the finish floor moving both up and down and laterally at those joints. Being that the subfloor boards were so narrow, alot of the 2-1/4" joints were going to be near or on top of those sub-floor joints. If you don't have stair or adjacent floor height issues, I would consider laying down 1/4" plywood over the subfloor and then the new oak flooring.
two things -
I don't think the OP said oak - he is using pine for new floor.
And 1/4" will not provide any nail base. It will help smooth the suace, but it is not enough to hold a fastener from the new flooring.
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It will help smooth the suace, but it is not enough to hold a fastener from the new flooring.
I think the smoothing of the surface is all he's looking for, so long as the existing subfloor is stable.
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Right, pine, I wasn't paying attention. I still think 1/4" is enough. First, there will be plenty of nail (or staple) holding power with the existing subfloor below. The fasteners are driven at an angle through 1" of material. Second, I'm most concerned about any cupping of the subfloor telegraphing through at those parallel joints where they occur at the same breaking point. Third, I'm concerned that seasonal shrinkage will tend to be worse at those same joints, especially if those stacked joints occur at a wide subfloor joint. Lastly, I was trying to raise the floor as little as possible above the surrounding floors. I don't know if this is a concern or not, but it could be a factor.So, that's what went into my thoughts on the matter
Thanks for all of the input guys.
Wife says no to the diagonal finish floor...neat idea though.
I'm already looking at a 3/4" step up into the room with the finish floor (the rest of the upstairs is pine on joists with no subfloor--not ready for that project yet.) An extra 1/4- 1/2" may make it seem too disjointed, and when I eventually redo the rest of the upstairs..it will still step up.
I think I'm gona repalce the subfloor with new 3/4". The old boards may make some really nice "reclaimed" table tops, and I could use the exercise:) Plus I might find some bags of money or other treasure hidden in the floor.
Thanks for helping me think this through. I didn't want to do the extra work if it wasn't going to help the finished product.
Considering your elevations, that's probably your best solution. I would be tempted to screw the existing down and go from there, although, I don't know how bad the cupping is. You might consider 5/8" ply. for the sub. Dropping the elevation 1/8" at the door would be noticable.
As for the bags of money, best of luck. 30 yrs. and the best I found was one 1899 Indian head penny. That's it, I keep hoping though.
The half inch "step up" really wouldn't be much of an issue with a saddle or reduction strip at the transition.
But I do believe it was I who suggested replacing the subfloor altogether, so I should be entitled to a portion of any "bags of money", no?
Good luck man.
Democrats.The other white meat.
Another option is to just run the new flooring perp to the subfloor and parrallel to the joists - if the subfloor is solid.
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Piffen-
Thanks for that suggestion too. I ask the wife, but my bet is no. It won't match the rest of the house.
Everyone-
Thanks again guys.
I'll offer a 20% cut of all hidden treasure found during this project to the group for the help you've given here.
It is certainly better to have it diagonal, butin all my demo work, I would say that half of the subfloors I've seen run perp like yours.
If it is generally sound you can leave it. If you have the elevation dimension to be able to, it is better to add a 3/8" or 1/2" ply glued and screwed over this to provide a smooth and solid nailbase.
Welcome to the
Taunton University of Knowledge FHB Campus at Breaktime.
where ...
Excellence is its own reward!
Why not just nail your pine strip floor on the diagonal? It looks more interesting, gives you your extra stability, and - inexplicably - is the easier and cost-free solution to your dilemma. (OK, laying on the diagonal takes a bit more material and time, but not much.)
Good idea as a problem solver...not sure I'd wanna see diagonal flooring in a 1920s bungalow though.
jmac....Ideally removing the original subflooring and replacing with ply would be the way to go.
My second choice would be to laminate a layer of 1/2" ply atop the existing subfloor....glued and screwed....so long as finished floor height is not an issue.
But honestly....a bedroom doesn't see a tremendous amount of foot traffic. If the existing boards are as stable as you are suggesting, you'll likely be safe to screw them off and replace the damaged boards. (Not seeing what exactly you have, I'm envisioning a need for a layer of 1/4" so that flooring and subflooring seems don't fall together all to often.)
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Not common in a bungalow, but then neither are microwave ovens. I suggested it bec it seemed the OP was reluctant to pull up the good existing boards. Just running the boards perpendicular to the subfloor seems like it would be plenty braced and bridge any gaps. It'd depend on which direction the subfloor runs, if that would look OK. Or herringbone it, or...or...or...
No argument with the method.....certainly answers the stabilitly issue.
Democrats.The other white meat.