Stormdry Is a deeply penetrating water repellent cream for brick, stone and concrete. Due to its cream-based formulation it is able to penetrate more deeply into masonry than standard liquid-applied. Water seal products. Stormdry is based on proven silane/siloxane technology and works by lining the pores of the masonry rather than blocking them – allowing the wall to continue to breath. Stormdry is easy to apply using a brush or roller and only a single coat application is required.