Shop Floor Sleepers

[Mike Kelsey]

After researching workshop forums, I think I'm ready to begin my wooden floor installation in the graveled barn/shop. The consensus is to lay sleepers wide side down, I assume for a greater surface to attach the floor to. Since I will be using 2X4's as sleepers & 3/4" OSB T&G, what is the recommended screw length? Originally I thought I'd go with 2" screws but I'm concerned with over driving a screw a 1/4" & puncturing the vapor barrier. Are there
1 7/8" deck screws or is 1 1/2" enough bit?

[Joe A Faulkner]

Mike, I think most folks lay the sleepers wide side down because they are putting raised floors in basements or in garages with 8' ceilings. In these applications they are trying to maximize head room. If your application is going in a barn, over gravel, you may want to consider other options depending on your ceiling height.

[Todd Crawford]

Wood is MUCH stronger in the thin side top/bottom than in the direction that you mentioned.

[Jim Andrew]

I think if you are careful, 2" screws will be fine. Just don't let the screws suck down into your plywood. Might help to drill holes through the ply. Flat boards laying on gravel should support your floor fine. It's not spanning anything. Probably help if your gravel is well packed.

[Ben Hatcher]

Anything you put on top of a vapor barrier sitting on gravel will punch holes in that vapor barrier.

[Mike Kelsey]

Anything you put on top of a vapor barrier sitting on gravel will punch holes in that vapor barrier.

Ben,

A good point I totally overlooked. I should put the sleepers down first, then the vapor barrier... Thanks

[David Gutierrez]

3/4" plywd on 1.5" thick 2x sleepers is a total of 2 1/4" of wood. 2" long screws will be fine. you would have to work at over driving the screws a 1/4" deep into the plywood. But if you are that concerned use 1 1/2" screws they should be fine if they have 3/4" of bite even if you do not over drive them.