What is a sub-slab depressurization system (also known as a mitigation system)?
A sub-slab depressurization system essentially prevents vapors beneath a slab from entering a building. A low amount of suction is applied below the foundation of the building and the vapors are vented to the outside (see figure below). Mitigation systems are inspected to insure that they are effective and that they do not cause any back-drafting. The system uses minimal electricity and should not noticeably affect heating and cooling efficiency.
