PREMIUM High-Strength Wall Water Sealer for Brick, Stone, Mortar, Sandstone and Granite. 25 YEAR PROTECTION Stormdry’s cream-based formulation allows it to Penetrate Deeply forming an invisible Water Repellent barrier in a Single Coat Application. BREATHABLE Allows masonry to breathe and dry naturally. Easy to Apply Penetrating Damp Treatment that maintains thermal properties of cavity wall insulation. Fully cured Stormdry brick damp seal will maintain natural appearance of the wall. INDEPENDENTLY APPROVED, TESTED & VERIFIED:?? BBA Approved (Certificate Number: 15/5198);?? Verified by the Energy Savings Trust as an energy saving method;?? Tested by University of Portsmouth.