Installing wood floor over a slab
DouglasCochrane
| Posted in Construction Techniques on
I’m converting half the garage at our beach house to a casita for the kids and grandkids. I’d like to put a wood floor in over the slab. Any suggestions of the best way to do so?
Replies
A lot depends on how the space will be heated. Can you describe the situation?
How much height buildup can you tolerate? In a year-round house in a cold climate, with hydronic radiant heat in the slab, I was successful gluing 3/4" CDX to the slab, then doing 2-1/4" quartersawn white oak atop, fixing with shorter nail cleats than normal, so they wouldn't drive through the plywood.
Have you considered something like Pergo or Wilsonart's competitive product?
Gene Davis, Davis Housewrights, Inc., Lake Placid, NY
Gene,
The space is about 250 SF. It is well insulated and has two Cadet electric wall heaters so it heats up in about 3 minutes. It won't always be heated as it will be a guest house and occasional craft room.
The Oregon coast is fairly moderate. Temperatures range from 45-65 degrees most of the time. It rarely freezes here and only gets hot (like in the 80's) for a few days of the year.
Although it is only a converted garage, I am trying to make it really old-time cottagey. For example there will be raised panel wainscoting, crown moldings, and lots of woodwork. So I just don't think Pergo is suitable for the look and feel I am going for.
On the other hand, if the wood floor warps that probably won't get me there either.
Height-wise, the entry area has a 7' ceiling with a Crow's Nest and sleeping loft above. The rest is a vaulted ceiling. So I could lose a couple of inches but would rather not go more than that.
Thanks for your advice,
Douglas
I'm certainly not selling Pergo or Wilsonart flooring, but some of their premium products certainly look like real wood, and come without the problems. Take a look in a showroom somewhere before you make your final decision.
The major wood flooring manufacturers association approves a glue-down on a concrete slab, provided it is not "below grade." Read: basement.
A guy I know in town builds megacamps for the rich and famous. Ultra rustic, ultra expensive, costs in the $350 per square foot and up range. He is sold on a glue down method using the Sika Acoubond system. Google for it and you will see what it is in detail.
What I like about the laminate floor installations (Pergo, etc.) is the cushy feel you get when stepping and walking, a result of the foam sheet underlayment. You get the same thing from the Sika system.
Sika Acoubond is a system of perforated foam underlayment and special polyurethane (a one-part moisture curing type) applied with their special gun tips. The real wood floor is bonded to the substrate (in your case, concrete) while being cushioned by the mat and able to expand and contract with moisture content change.Gene Davis, Davis Housewrights, Inc., Lake Placid, NY
Gene,
Thanks for the advice on the Sik Acoubond product. It looks good.
I got a great deal on enough Brazilian Cherrywood to do my little project. Can hardly wait to get started. I'll let you know how it goes.
Fine Homebuilding is a great magazine and this is a great website for the Beach Bums and Wannabe's.
Cheers!
Douglas Cochrane
I am imagining that nice cushy feel of your new wood floor over the Sika installation system. Please post a followup if you use it, and tell us how it went, and include photos of both installation, and finish.Gene Davis, Davis Housewrights, Inc., Lake Placid, NY
Would you recommend the 3mm or the 5mm product for a 3/4" solid wood floor?
I have seen good results with the 3mm. You'll experience the cushion you need, and material costs will be less.
Are you doing this yourself, or will you be having a flooring contractor do it? Either way, installation will require some sort of jacking or clamping devices, the sort that are used to push or pull joints together. Jacks or clamps are used for any kind of gluedown installation.Gene Davis, Davis Housewrights, Inc., Lake Placid, NY
Gene,
I've searched high and low locally and on the Internet and can't find a supplier who sells the Sika Acoubond product. I only need about 210 SF. Can I get it from you or can you send me to your supplier?
Thanks for your help.
Douglas Cochrane
[email protected]
Check out the website for the Hardwood Manufacturers Association(Google it) they have some good descriptions and details for hardwood over concrete.
We used their reccomendations to put random width walnut floor over a concrete slab in a $2 million dollar house and it was relatively easy and turned out good.
I'm not sure if they reccomended it but seal the concrete first with a good concrete/masonry sealer and put 1 1/2" foam between the sleepers for insulation and to deaden sound when walking on it.