I recently installed approximately 5000 SF of 5 1/2″ tounge and groove oak flooring in a home. The floors have been installed now for about 8 months and one room in the house is cupping rather severly while the rest of the house is perfectly flat. This room is an addition over a crawl which is sealed and very dry. We checked the moisture levels in the crawl and house today and they range from 68% in the crawl to 60% throughout the entire house. I have not checked the moisture content of the floor but I am going to assume it is on the high side for this room. The flooring was installed at the same time and this room was the last to be installed. All of the material sat in the house for over 2 weeks. The flooring was installed onto a 3/4″ sub floor over a moisture barrier. I have no idea what could be causing this problem. My solution is to cut a return in the crawl to increase air flow below the room. This crawl is about 800 cubic feet with foam on the 3 outside walls and a plastic vapor barrier over the ground. It is dry and shows no signs of moisture.
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The flooring was installed onto a 3/4" sub floor over a moisture barrier.
What was your moisture barrier?
Between the plywood sub floor and wood floor we installed a vapor barrier that was supplied be the vendor which is a heavy duty plastic material which was supposed to be a better alternative than felt or rosin paper.
I have no idea.
Best of luck
what is the temp dif between crawl and the room, condensation must be forming on the vb ..
not much consolation now, but the wide plank flooring is all the designers rage, there is a reason why they switched to narrow boards as soon as sawmills came into their own ..
"The floors have been installed now for about 8 months and one room in the house is cupping rather severly while the rest of the house is perfectly flat. "
Something is happening in the crawl space below the cupping floor-before you cut the vent...look carefully...hotter/colder/more moisture in this crawl area??
or it could be in that room-hotter/colder/more moisture-heat source??
windows open??
silver
This is in Louisville KY. Very humid this time of year. The owner does not use the room a bunch and it is zoned with its own thermostat. I advised them to leave the fan on. All exterior walls are 2x6 with closed cell foam. I am going to place a commercial dehu in the crawl and attempt to pull what moisture is down there out.
You're only having a problem in the one room-it's localized...the other rooms are ok so drastically changing all the crawl space humidity may not be the answer.Does the room with the problem get more sun?I'm pretty sure there is an other factor besides crawl space humidity-why aren't all the floors cupped-did you change the paper/vapor barrier in that room? slightly different product?I had a problem in a similar situation once and it was a temperature problem-raised temp in crawl space-no problem.good luck-silver
spray foam or cut/nail/ seal foam sheets to underside of floor. Floor will lay back down. Same thing happened on one uninsulated section of my house. It is fine now.
I thought about this yesterday when I was on a bike ride...the room with the problem has been closed off-and probably overheated...ventilate the room-no problemsilver
68% moisture is not dry
This room is an addition over a crawl which is sealed and very dry