Xynpol AO557L provides excellent water vapour barrier performance. Formulation XSC15, (below), was tested in accordance with ISO 7783:2011. A dry film of 250 μm yielded Class 3 performance after 14 days, (Diffusion equivalent air thickness (sD) >1.4m). Typically, the membrane is applied over smooth floated concrete floors, using a roller and two coatings, the second coat at right angles to the first, to ensure optimum sealing of the concrete surface. Application of 0.2kg/m2 per coating is recommended, higher coat weights may be necessary for rough aggregate or uneven surfaces.The concrete should be fully cured and dry before the barrier coating is applied and allowing sufficient drying time between coatings according to site conditions. A colourant is often added to the formulation to ensure that complete coverage is evident.
