Sleepers over concrete?

[Jim Mackell]

Friend lives in a garage apartment, over the garage. They are thinking of expanding into both floors. Creating inside stairs, kitchen on first floor, bedrooms on 2nd, etc. Would double their available living space.

The garage of course has a concrete floor. It's been suggested that they place a layer of 2 inch foam board down and then place 2 x 4 sleepers with a plywwod floor screwed to the sleepers.

Anyone have any experience with this? Appreciate opinions pro or con. Thanks1

[Jim Matthews]

I have done something similar with OrVX panels.

They're tongue and groove to fit together.
The bottom is polystyrene, the top is OSB.

You can skip the vapor barrier with these, and they knock together quickly.
You can tile directly over the OSB.

http://barricadesubfloor.com/

[Jerome Stanek]

When I was building Revco drug stores that is how we did the pharmacies and it worked out really good

[Jim Becker]

Sleepers and foam insulation is pretty much a standard way of doing this conversion...don't forget you need to compensate for the slope that most garages have in that respect.

[Lon Crosby]

Put the foam down, tape the seams and cover with T&G plywood with glued T&G's with biscuits on the ends. Forget the sleepers. You save 2" in height, a lot of work. If you like to worry, use high density foam.

[Jim Mackell]

with glued T&G's with biscuits on the ends.

Lon, not sure I understand that portion of your sentence. Could you explain just a bit more? Thanks!

[Jim Becker]

Lon, that will work beautifully if the floor is flat, but typically garage floors slope from the back to the front...

That said, if this method is used and there is any partitioning going on in the space, that should still be accounted for so that the wall is bearing on the concrete, not on the plywood that's floating on the foam insulation.

[Chris Padilla]

Ah, yes, the (somewhat) annoying sloped garage floor syndrome.... It always attacks when least (remembered) expected.

[Lon Crosby]

Jim, You want to keep the square 4' edges of the T&G aligned as well as the 8' edges. The easiest way is to do this is with biscuits.

The easiest way to level garage floors is with self-leveling cement. You could also use real cement but that is work. In a barn workshop, I am actually using plywood/insulation over a coarse sand base which is screeded. In difficult areas, I spray acrylic polymer over the sand to keep things in place until I get back to it.

[Steve Peterson]

Jim, You want to keep the square 4' edges of the T&G aligned as well as the 8' edges. The easiest way is to do this is with biscuits.

The T&G flooring that I am familiar with from the big box stores has tongue and groove on all 4 sides. A biscuit seems redundant.

Steve

[Scott Schwake]

How do you handle inward-swinging doors with this method?

Scott