Best Vapor Barrier For Concrete Slab

She s planning to pour a new layer of concrete over the old and wonders what type of vapor barrier she should use.

Best vapor barrier for concrete slab.

Place the vapor retarder on top of the granular material and directly beneath the slab for moisture sensitive floor covering and coating applications. Best 6 mil vapor barrier underlayment by flooring type all flooring moistureblock. Recently though research has shown that the old traditional layer of 6 mil visqueen polyethylene plastic under the slab is seldom effective for two main reasons. View product where.

Consider using concrete having a w c not greater than 0 45 to hasten slab drying time. To take it one step further astm e 1745 class a vapor barriers products with less than 0 01 perms are the best approach to protecting your concrete slab and components moisture sensitive floor and iaq from moisture sources below. Uncontrolled water vapor through concrete slabs has cost building owners designers and contractors billions of dollars. The best vapor barriers for concrete floors and slabs are a new generation of poly made from high quality polyolefin resins that are designed to ensure low permeability high tensile strength and superior puncture resistance compared to regular polyethylene sheeting.

Since concrete is porous water vapors transmits from the ground through the concrete slab into your basement. It needs to dry and then stay dry to avoid flooring problems. Use of fly ash may help reduce soluble alkali content in the slab. Vapor barriers are used because while fresh concrete is poured wet it s not supposed to stay that way.

Vapor retarders have been used since the 1950s. The best way to accomplish that is with a vapor barrier under the slab. Vapor and gas barriers. That s the subject of this week s q a spotlight.

A concrete vapor barrier is any material that prevents moisture from entering a concrete slab. The use of underslab vapor barriers is the best method and most economical solution for controlling water vapor migration through concrete slabs. Block or create a true impermeable barrier. The usual solution would be 6 mil polyethylene with taped seams but a number of posters think there are much better products on the market.