An integrated powder collection system for paint spray booths is provided for paint spray booths having a floor through which overspray and air are exhausted. The powder collection system includes at least two sloped surfaces disposed beneath the floor for defining at least one longitudinal slot therebetween. At least one longitudinal air slide is disposed beneath the at least one slot, and a pulsed vacuum source is connected to a filter cassette which is disposed beneath the floor and laterally to a side of a space defined vertically below the at least one longitudinal slot.