Concrete floor problems building science corporationwhy a plastic vapor barrier under concrete slab mondays withinstall the proper type of vapor barrier siouxland homesunder slab vapor barriers done. Under monolithic concrete slab bsi 082 walking the plank building slab vapor barrier by professional concrete floor problems building how to carpet a bat floor the vapor barrier. Astm e 1643 standard practice for installation of vapor retarders used in contact with earth or granular fill under concrete slabs provides details but here are a few tips.
Find out where to buy vapor barriers and other problem solving products. To be effective a vapor barrier must be installed in a way that prevents any water vapor from getting to the slab. This guide says in section 2 4 1.
Aci 302 1r 11 guide for concrete floor and slab construction doesn t advocate universal use of vapor barriers but does make recommendations for their proper use. It is also possible that too much water or cement paste would be absorbed from the concrete by the sand but probably not under most circumstances. But they have also proven to be beneficial in reducing failures of moisture sensitive flooring materials adhesives and coatings caused by excessive emission of moisture vapor from concrete slabs.
Vapor barriers have been associated with certain concrete slab on grade problems including curling and cracking. The term vapor barrier is often used interchangeably with the term vapor retarder to describe all membranes used to resist water vapor transmission. A vapor barrier is an impermeable membrane primarily used to resist water vapor transmission from the soil to the concrete slab.
A vapor barrier should be used for all concrete floors and slabs that are going to receive an impermeable floor finish like epoxy laminate linoleum and wood or if the concrete floor will be used for any purpose where the passage of water vapor through the floor may create problems. Aci 302 1 guide for concrete floor and slab construction states that the minimum thickness of an effective vapor barrier is 10 mils. The other characteristic of a good vapor barrier that makes it effective is resistance to punctures and tears.
Vapor and gas barriers. The use of underslab vapor barriers is the best method and most economical solution for controlling water vapor migration through concrete slabs. Uncontrolled water vapor through concrete slabs has cost building owners designers and contractors billions of dollars.
Aci 302 1 which is an american concrete institute standard for slab construction was modified in the early 2000 s to reflect the change in the placement of the vapor barrier directly below the concrete if a low permeable membrane flooring was to be installed.
