[photolew]

I moved to this home about 15 years ago and converted an old garage into living space. One of the issues that would have been MUCH easier to deal with was the fact that the floor was poured in multiple sections, that don't line up all that well.

The ultimate goal is to install a laminate hardwood floor in the space. My current thought process is to use some self leveling underlayment to take care of the majority of the uneveness (we are talking under 1/2" issues) and then put down a layer of plywood before the laminate flooring.

My question is how to affix the plywood to the concrete? I would think glue would be a very poor choice (jsut guessing), I could use tapcon screws, but I'd prefer not to have to do all that drilling....but if I have to I have to

Any other options that might be less labor intensive?

 

[SteveSmith98]

Total amateur here, so beware. But:

1) If you put the plywood right on the concrete, it will rot. Concrete will wick moisture out of the ground into the wood. You need a vapour barrier in-between.

2) Consider using something like a Dricore panel and leveling kits.

3) If you are fastening to concrete, you might want to consider a ramset tool.

But I don't believe any of this should be necessary. If you can level out with the compound, then the laminate can be installed directly on top of a vapour barrier (which the underlayment should act as).

Depending on your climate, you might want to put the effort in to insulate the floor with rigid foam.

 

[photolew]

I guess I should add that one of the other side benefits of added the additional subfloor is that and adjacent room has a floor level that is close, but not quite the same height....the new subfloor is to help address that issue as well

Im thinking the ram set may be the way to go.....

 

[Grampa Bud]

ORRRR you may have answered your own question in the first place. Any self-leveling cement applied in adequate quantity will find its level plane from 1/8 in. to as deep as 1 1/2 in. If you have the time and mix a real watery slurry as in Gypcrete for radiant floors you can actually go from 0 in. to 1 1/2 in. The extra time involved is to let all the moisture evaporate out. At this point you would not need any 'underlayment' at all if you put down the thin foam pad rolls or sheets for the snap and lock wood flooring systems. Just be carefull to lightly butt the foam edges up to your walls and use duct tape to join all the seams in the rolls or sheets. You would have your vapor barrier -which you do need- and your hardwood floor which you want and no plywood underlayment.

 

[Bronx]

Slpit drive anchor

I have fastened plywood to concrete on a couple of jobs and both times I used a split drive anchor. It is easy to use and has a countersunk head that will be flush with the wood. First you drill a 1/4 inch hole through the wood into the concrete. Next you drive the anchor into the concrete with a hammer. There is a installation video on www.confast.com You will still have to drill a hole but it is less time consuming than a tapcon.

 

[Scuba_Dave]

Why not build a 2x3 floor, shim & insulate?
You will find that concrete will be very cold in the winter

 

[RegeSullivan]

If your up for something unconventional - here's what I did on and enclosed porch that was constructed on a concrete patio. The owners (relatives of mine) wanted the floor level with the entry way and were concerned about a cold floor since this would be used as a sitting-reading room. It needed to be done really quickly for a party that was planed for the coming weekend...

I needed to make up just over 2 inches so I put down2 inch foam insulation with vapor barrier , taped the seems with foil tape and put a cheap floating floor right over it and immediately iced down 8 cases of beer in coolers. I was afraid it would be temporary... that was Christmas 1999. Last year the floor need replacing and when it was pulled up the foam looked like the day it was put down. We just put down a new floor but better quality this time.

Rege