Vapor Barrier Under Cement Slab

Chemical resistance consideration if a vapor barrier is being used under a slab to control vapors at a brownfields site the chemical resistance of the vapor barrier must be considered.

Vapor barrier under cement slab.

Reinforcing has to be supported so that it is in the top 1 2 to 1 3 of the depth of the slab throughout the pour. If heavy equipment will be operating on the vapor barrier or if the vapor barrier will be installed over an angular subbase a minimum of 15 mils is recommended. Meadows vapor barrier is called perminator it also comes in 10 mil and. To be effective a vapor barrier must be installed in a way that prevents any water vapor from getting to the slab.

In the past i ve used 6 mil poly as a vapor barrier under concrete floors and slabs and will say it is easily punctured the stego wrap is much more puncture resistant. A much better approach is a true vapor barrier with characteristics that conform to the requirements of astm e 1745 standard specification for water vapor retarders used in contact with soil or granular fill under concrete slabs. Find out where to buy vapor barriers and other problem solving products. Why and how is there moisture in concrete slabs.

Thin plastic like this is often called a vapor retarder meaning it slows the vapor down but doesn t stop it. By steve ragan director research and technical services the answer to this controversial question from both angles is a qualified yes vapor barriers have been associated with certain concrete slab on grade problems including curling and cracking. 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. Its not required for accessory structure storage rooms under 70 sf flatwork that isn t enclosed and other approved site conditions.

There needs to be a vapor retarder at least 6 mil between the base course and the slab. Should you put a vapor barrier under concrete slabs. 2 4 how to install vapor barrier on concrete floor under laminate flooring. A high performance vapor barrier once again can eliminate one of the variables which leads to the condition in the first place.

Too much moisture in concrete is a problem because it can cause ph changes that destroy adhesives. Astm international gives specific guidelines in astm e1745 17 and astm e1643 for the use installation and inspection of vapor barriers used under concrete slabs. By reducing the moisture gradient and diffusion in your slab you can virtually eliminate efflorescence caused by under slab water vapor migration. Months or years from now the water table link might rise and the water will pass through concrete in water vapors with a.

Vapor barriers under concrete floor slabs. Why is too much moisture in concrete a problem. Florprufe vapor barriers gcp lied slab vapor barrier by professional concrete floor problems building under monolithic concrete slab 10 and 15 mil underslab vapor barrier concrete vapor barriers ers.