Ventilated, drained facade assemblies that manage water instead of trying to block it
A rain screen is a wall built on the assumption that some water will always get past the outer surface. Rather than relying on a single sealed skin to stop everything, the assembly is designed to catch that water, drain it back out, and dry the cavity between wetting events.
The outer cladding is the first line of defence, but it is not the waterproofing. Behind it sits a ventilated and drained cavity, and behind that a continuous air and water-resistive barrier applied to the substrate. That barrier is the actual weatherproofing layer. Water that penetrates the cladding runs down the back face, hits flashing, and exits through weeps at the base of the cavity.
This matters because face-sealed walls fail in a specific way: they depend entirely on sealant joints, and sealant has a finite service life. When a joint fails on a face-sealed wall, water enters the building with nowhere to go. When a joint fails on a rain screen, the water lands in a cavity built to drain it.
We build rain-screen facades across New York City and Long Island, on new construction and over existing masonry. The composite slat cladding on Coney Island Avenue in Brooklyn and the black ACM panels and Blueskin air barrier on the Amherst Drive house in Woodmere are the two current examples, with the ACM and canopy package at 2535 Frederick Douglass Boulevard in Harlem the commercial one. The newest is 75-65 186th Street in Fresh Meadows, Queens: ACM and wood-look rigid panels with an entrance canopy on a substructure over 3 inches of insulation. Local Law 11 facade cycles in Manhattan and Brooklyn are often where a rain screen enters the conversation; see waterproofing for how we detail the cavity.