MPC-180 fast cure moisture vapor barrier is a 100% solids, a two-component epoxy coating designed for controlling moisture vapor emissions on new or deteriorated concrete floors. Apply at a thickness of 18 mils, it exceeds ASTM F3010 product requirements for vapor permeance. This coating withstands moisture vapor emission rates up to 25lbs./24hrs./1000 ft2 when applied properly.
A vapor barrier is any material used for damp proofing, typically a plastic or foil sheet, that resists diffusion of moisture through the wall, floor, ceiling, or roof assemblies of buildings to prevent interstitial condensation. Technically, many of these materials are only vapor retarders as they have varying degrees of permeability.
Vapor diffusion retarders are normally available as coatings or membranes. The membranes are technically flexible and thin materials, but sometimes include thicker sheet materials named “structural” vapor diffusion retarders. The vapor diffusion retarders vary from all kinds of materials and keep updating every day. Also some of them nowadays even combined the functions of other building materials.
Moisture or water vapor moves into building cavities in three ways: 1) With air currents, 2) By diffusion through materials, 3) By heat transfer. Of these three, air movement accounts for more than 98% of all water vapor movement in building cavities. A vapor retarder and an air barrier serve to reduce this problem but are not necessarily interchangeable. Vapor retarders slow the rate of vapor diffusion into the thermal envelope of a structure. Other wetting mechanisms, such as wind-borne rain, capillary wicking of ground moisture, air transport (infiltration), are equally important.