Vapor barrier

Strach · 07-12-2010, 12:59 PM

Trying to apply resilient sheet flooring on top of a concrete slab. The only catch is that I need the floor to be a little warmer on your feet. I was going to paint one side of the plywood that is facing the concrete to seal the ply. Under that I was going to lay down a 6 mill poly down. Do you think it will be sufficient for moisture control

Strach · 07-13-2010, 02:24 PM

I am working on a five year old slab on grade commercial building. I would like to put a preticular sheet flooring for my finish. Inorder to make the space warmer I thought I could put 6mil poly on the floor plus 5/8 t&g painted one side ( to seal it), then my vinyl.
Does anyone think that is retarded or should put sleepers for air flow

**Gary in WA** · 07-13-2010, 07:12 PM

Not if the vapor barrier is missing under the slab, or has any holes or unglued laps for water tight.

http://www.100khouse.com/2009/06/24/...b-air-sealing/

http://www.buildingscience.com/docum...ms?full_view=1

Be safe, Gary

stubborn1 · 07-13-2010, 08:33 PM

The extra vapor barrier and plywood seems pretty unnecessary. If you are in a cold climate, they should have insulated the frost walls and provided a thermal break at the intersection of the slab and foundation.

Strach · 07-13-2010, 09:55 PM

The building is becoming a yoga studio and having a softer and warmer floor is apperently something that the client would like. Would the sheet flooring that is going on top of the plywood be really hard and cold directly on the slab.
The studio is in a cold climate. Is there a need to put a vapor barrier between the slab and plywood due to possible moisture?

JazMan · 07-13-2010, 10:49 PM

If you try to put a poly on the floor you will have a mess in a few years. If you also cover it with ply, OSB or any other similar material you will have a royal mess. It will not work long term. Where is the moisture in the concrete going to go?

Jaz

rusty baker · 07-13-2010, 11:06 PM

Quote:

Originally Posted by JazMan

If you try to put a poly on the floor you will have a mess in a few years. If you also cover it with ply, OSB or any other similar material you will have a royal mess. It will not work long term. Where is the moisture in the concrete going to go?

Jaz

Same thing I said in the building and construction forum.

Strach · 07-14-2010, 07:08 AM

So is my only solution to put sleepers down with poly under just the sleeper then lay plywood? Or would you recommend just lay the sheet flooring down on the conrete like it is intended to be

**Gary in WA** · 07-16-2010, 05:56 PM

http://www.buildingscience.com/docum...ms?full_view=1

Be safe, Gary