MOISTURE VAPOR MITIGATION | |||
Concreteslabs on grade that have not been poured over an effective vapor retarder are subject to high levels of moisture vapor emissions that can cause failures in flooring adhered to the concrete. For this to occur, two additional conditions must be met — the concrete must have a well developed pore structure to transport the moisture and there must be a continuous source of moisture under the slab. Concrete poured with a high water to cement ratio results in an unusually permeable slab that readily allows moisture to move through it. Sources of moisture are usually plentiful — seasonal rains, landscape irrigation, snowbanking, a broken pipe or soil that stays continuously wet through capillary rise from the water table. As moisture vapor moves through the concrete, it carries soluble alkaline materials always found in concrete such as sodium, potassium and calcium hydroxides. As these corrosive materials become concentrated in the upper portions of the concrete, they can damage the flooring systems or the concrete itself. This damage may be evidenced by disbonding, adhesive breakdown, osmotic blisters, mold or staining. Ervin Specialty Coatings can design a Moisture Vapor Mitigation system to meet your flooring needs. | |||
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