Morrison Hershfield Limited undertook to study and investigate the performance of the Rainscreen Principle applied to residential claddings on wood frame construction for the Canada Mortgage and Housing Corporation. The study included a full scale simulation, in the laboratory, of the rain penetration control performance of three cladding types with each having a sealed and leaky air barrier system. The three cladding types include vinyl siding, stucco, and a brick veneer. Ail cladding systems were mounted on a conventional wood frame wall.