Gap or not?

[Cliff Polubinsky]

The new shop is coming along. Should be about finished with the electrical tonight. Then the insulation and close up the walls. Which is where my next question comes in. I'll be using 7/16 OSB for the walls. The floor is plywood (the building was built with a wood floor on concrete pillars). I'm considering laying another layer on the floor, either DRIcore, another layer of plywood or OSB or possibly a regular hardwood floor.

Should I leave a gap between the wall OSB and the floor and if so, how much? Or should I just run the OSB all the way down and plan on butting the floor against the wall?

Thanks for your thoughts.

Cliff

[Charles Lent]

I wouldn't use OSB for the top layer of a floor. I've been to several shops with OSB floors and the floors are de-laminating, with wafer chunks of the OSB surface coming up in many places. It makes a good sub floor, but not the top surface. My floor is T&G plywood and I haven't had any problems with it in the 25 years that my shop has existed. OSB on the walls is OK if you don't mind the appearance. I would put the smoothest side out and then paint it. Since plywood and OSB size changes less with humidity changes I feel that a very small gap of 1/8" or less every 4' is all that is necessary.

Charley

[Dennis McDonaugh]

Ditto, the OSB seems fine as long as its not exposed to traffic.

[Val Kosmider]

I know people seem to use plywood and OSB interchangeably. And we probably all would agree that OSB is a 'weaker' product in many ways.

This was recently demonstrated quite harshly with a little test that they did on TOH.

The were looking at materials to put over windows and doors to prevent damage from hurricanes. They covered the window with a sheet of OSB and then launched a projectile at it. The projectile went through it like a bullet, with virtually no resistance.

They repreated the test with plywood and the projectile bounced off the surface, with no penetration.

It was a real eye opener for me as to how different the two projects really are. I cannot imagine a floor having any wearabiity with OSB.

[Michael W. Clark]

IME, the wall coverings are installed first, then the floor is installed between the walls. You can install baseboard if you want to cover the gap between the floor and the wall.

I used OSB on my shop walls in the basement, slick side toward the shop. I used a piece of the OSB to set it above the concrete floor (~1/2"). I fastened it with construction adhesive and 16ga finish nails. Anything heavy still gets screwed to the studs (lumber rack, cabinets, clamp racks, etc).

[glenn bradley]

OK, I'll chime in. I would use something other than OSB on a floor. I would leave a gap between the floor material and the wallboard for movement and cover the gap with strips of trim to keep it from catching "everything". My OSB walls have worked out great but, OSB floor surfaces delaminate.