Outside Perimeter Drainage System
Exterior Waterproofing & Drainage Systems are the best protection for a crawlspace against ground water. It is used almost exclusively when houses are being built.
In “retrofit” situations, houses with established landscaping, connected utilities, air conditioners, patios, decks, additions, garages, etc., exterior waterproofing can be at best impractical—if not close to impossible. However, some homes are ideal candidates for our external perimeter drainage system.
Exterior Waterproofing prevents water from entering into a crawlspace. In order for a crawlspace foundation to be completely waterproof, it needs to have protection from surface and ground water for all of the below grade walls. All of this protection must span from the surface down to a depth deeper than the crawlspace floor.
The Crawlspace Company trenches around the perimeter of your home to a depth deeper than the crawlspace floor. Sometimes this depth can range from 3′ to 6′. The foundation wall are then cleaned of debris. A 20 mil cord reinforced polyethylene barrier is fastened to the foundation wall. This is the last line of defense against water. After the liner is attached, a dimple core composite drainage matting (J-Drain) is attached to the wall. This drainage matting is the material that will divert hydrostatic pressure (water table) to the footing drain. After the drainage matting, a perforated pipe is installed beside the footing and is encompassed with a rock backfill. The drainage pipe is either carried away from the home through a gravity drain or diverted into a sump pump system.
Our outside footing drainage system has been considered “overkill” by other drainage contractors, but we know that it is the only time-tested system that works. Crawlspace Foundation Sealants will only last at best 2 to 5 years. Our materials carry a lifetime transferrable warranty.