Description Using negative pressure to simulate and test resistance to wind induced uplift on a membrane roof system.
Test Summary Test pressures are obtained from the structural engineer and/or governing agency. These usually include field, perimeter, and corner test pressures. The apparatus is installed and pressure is gradually increased to the test pressure in 7.5 psf increments (held for one minute) while simultaneously recording the deflection of the membrane. Failure is 0.25 to 0.94 of an inch deflection (FM) and one inch (ASTM).