This technical bulletin explains the importance of water management in walls and covers the ASTM E2273 standard, as well as the importance of this test in terms of the drainage efficiency of a wall assembly. DuPont recently tested the drainage efficiency of DuPont™ Tyvek® HomeWrap® at a third party and it was determined that Tyvek® HomeWrap® and Tyvek® CommercialWrap® have a drainage efficiency of greater than 90%.