Glad to see this message board up - I never got to see the previous one!

As you will soon tell, I am a complete newbie to the world of hardwood flooring - but I am learning quickly!

So here's question #1 - we are in new construction, going over concrete -
what's the better option: engineered or solid - and if solid, what is the maximum thickness you would recommend (9/16"?) PS - we are in Austin, TX - where it's hot most of the time! Is it true that we should use spacers every 10 boards or so to allow for expansion in the case of solid?

Question #2 - what is the better option between glue-down and floating - I don't know what to consider? are specific products made only for glue-down or floating or can the same product be done either way?

I guess I should take this one...


Personally, I will not install a solid wood over concrete, even if the installation instructions say you can do it. It is a very, very risky installation. The risks are too high for my reputation. I never lost money on a job I didn't do!

New construction and high Moisture Vapor Emissions are go hand in hand!

Even old slabs here in Austin can read high, because of the hills (The Texas Hillcountry!!)

As a NWFA Inspector also, I inspect at least one thin solid a week, that has been glued down to the slab. cupped and buckled is the claim

An engineered cross-ply is made for gluing down to concrete, because it is more dimensionally stable.
If it were not for concrete, I bet we would never have engineered wood flooring!

The concrete still needs to be tested for high vapor emissions.

Don't even think about floating a solid. Some of the T&G on engineered wood are not milled tight enough to get good compression, penetration and adhesion, of the T&G glue. So never assume all T&G wood floors can be floated.

Engineered is the smart choice over concrete.

If you go with something solid,it should be as thin as possible. Bruce had a solid 5/16 product called Natural Reflections. I have installed it over dry slabs. Millions of feet of parquet have been installed over concrete with success. Being only 1/4 inch thick is what allows it to sort of dodge the water bullet. The thicker the product,the more capacity it has to absorb and hold water. That is when the stuff hits the fan.

Floating over a vapor barrier can eliminate many moisture concerns. It is no panacea,though.

By the way,proper testing can only be done after the Hvac system is up and running. In a new home,even that is not as reliable as some would lead you to believe. A new slab will make a lot of vapor the first time you crank the heat up.

Happy shopping,

Chuck.

I agree with all that has been said regarding going over concrete with hardwood. However, there is one solid wood floor brand that is designed to be floated and works quite well. That brand is Junkers and it utilizes a clip system to attach the boards together . As stated before, a slab still needs to be moisture tested. If one insists on a solid wood floor over concrete, this is one option to consider. Another is to build a 3/4" plywood subfloor on the slab and install solid flooring over that. One still needs to moisture test the slab. In the past, what I've done is lay inexpensive vinyl sheet flooring as a moisture barrier, then glue (with a urethane adhesive, full spread) and nail down the plywood. This will provide a stable nailing surface for the wood flooring. I've never had this system fail. It is expensive. IMO, the easiest way is to install a engineered longstrip floor that is designed to be floated. This system was made for slabs and works very well and is cost effective.

Hi, we are also looking at engineered floors for the first floor of an older home in Maryland that is built on a concrete slab. One flooring company has recommended floating the floor since the previous owners left some laminated tiles with asbestos underneath the carpet. He's recommending that we go with Boen Parkett, but I'm having trouble finding information/ratings about this company. Any opinions, pro or con?

Boen is as good as they get. If your contractor stands behind it and you trust your contractor, then go with it. Lots of brands of floating longstrip floors, most are good. A good system for going over concrete or problem floors. Prefinished engineered floors with an enhanced urethane finish will wear a little better than those that do not have additives in the finish. Always ask to see a sample and check to see how well the boards fit together. Should be nice and flush with little to no overwood. Also check the warranty and maintainenence instructions. Did you do a google search for boen?

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