We installed a new hardwood floor in the entire first level of our 32 year old house. Every board cupped. We can't find any measurable amount of moisture with a meter except in two small areas in the crawl space it's 14%. Not over 6% anywhere else. We used red rosin paper (builder paper)over the subfloor before laying the hardwood. Someone suggested it wasn't acceptable. What is the acceptable cover over the subfloor before the hardwood is laid? Any advise on why the whole 2200 square feet would cup when we don't have a major moisture problem?
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it is obvious from the cupping that you do have a sort of moisture problem, but ar ejust not reading it right. Some info is missin in the tale.
Any time that you have cupping, especially this consistant, it means that the back of the floorboards has more moisture than the front.
So either the moisture has come up from below, migrating into the flooring and expanding the back sides of it while the topside stayed the same
Or the flooring was laid too soon befoire it had stabilized to jobsite conditions, was more damp than itr should have been, and the top shrunk while the underside remained the same.
or a combination of the two.
Did you use the moisture meeter to study the flooring pieces on both sides and the subfloor before you installed and finished it. Thjey should not have been moire than 1 or 1-1/2° apart in readings.
Did you sticker the wood with good air circulation for ten to twenty days before installing it
Did you change anything else since the installation, like adding an air conditioner, starting to use one, or a dehumidifier since the installation. AC acts as a dehumidifier and will dry the air, shrinking the surface.
Excellence is its own reward!
Any time that you have cupping, especially this consistant, it means that the back of the floorboards has more moisture than the front.
So either the moisture has come up from below, migrating into the flooring and expanding the back sides of it while the topside stayed the same
Or the flooring was laid too soon befoire it had stabilized to jobsite conditions, was more damp than itr should have been, and the top shrunk while the underside remained the same.
or a combination of the two.
Did you use the moisture meeter to study the flooring pieces on both sides and the subfloor before you installed and finished it. Thjey should not have been moire than 1 or 1-1/2° apart in readings.
Did you sticker the wood with good air circulation for ten to twenty days before installing it
Did you change anything else since the installation, like adding an air conditioner, starting to use one, or a dehumidifier since the installation. AC acts as a dehumidifier and will dry the air, shrinking the surface.
Excellence is its own reward!















