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Hardwood flooring over concrete

We just bought a 4500 square foot ranch built in 1940. Most of the current flooring is carpet over concrete. Can we use regular hardwood flooring rather than engineered? What type of underlayment should we use? Our ceilings are 8 ft. tall, therefore plywood seems to raise the level of the floor too much. In addition, we would love to install radiant heat under the hardwood if possible. Any thoughts or suggestions?

Re: Hardwood flooring over concrete

Hardwood flooring is a beautiful natural flooring.... however ... it is very particular to moisture.

Once upon a time the suppliers were very cautious about installing hardwood on concrete slabs on grade and below grade because of moisture wicking through the slab and being absorbed by the hardwood. This usually results in the hardwood expanding too much or cupping ( warping).
Then magically the suppliers decided it was fine to install hardwood everywhere.

Now it's not to say it can't be done but there are particular circumstances that will allow for this. The main thing is a low moisture level from the slab .... very important to check with the flooring supplier and follow the manufacturers recommendations.

The other point is your desire to have radiant heat in the floor. Since you mentioned about not being keen to a subfloor installed because it would raise the floor height .... depending on which type of radiant heat you desire could require a thicker floor than you expect.
The hydronic floor radiant heat would probably require an inch thickness under the hardwood. The other alternative would be grids of electric radiant floor heat which wouldn't be as thick.

Just some thoughts.:)

Re: Hardwood flooring over concrete

It is possible but I wouldn't recommend it at all.

I have hardwood in my bedroom installed directly on the concrete slab. I don't like it because the little boards have many many crevices for moisture to penetrate. They used adhesive as the moisture barrier on the bottom but left a leaky roof to damage the top. The wood has expanded the only way it can, up, and this has pushed splintering points out.

Unfortunately they also didn't get certain sections square when they laid it and we have cracks in very visible areas.

My brother in law recently laid tongue and groove oak in his house using adhesive to secure it. It's only been a few months and he's seen things he doesn't like about the floor, like the seams opening up in weird places. He's not going to worry about it though, he just lost his house to foreclosure. Shoulda paid the mortgage rather than bought $4500 worth of flooring. Poor dude, his wife insisted that he do all this then she left a month after it was done taking half of the income with her.

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