French Drains
What is a French Drain?
A French Drain is a subsurface gravel filled drain with perforated pipe in the interior. The drain is constructed by excavating a ditch. The ditches dimensions vary depending on the amount of water the drain is expected to control. The ditch is filled with a small layer of gravel along the bottom, then perferated drain pipe is lain in the interior. The drain pipe’s dimensions can vary between four, six and eight inch pipe. Gravel is then backfilled. The gravel can be filled all the way to the soil grade or somewhat less depending on the requirements.
What is the difference in the drain pipe?
Corrugated pipe is cheaper, and easier to work with and most often quite adequate for the job at hand.
PVC pipe is stronger and resist crushing, moves more water and is able to have a “clean-out” installed for the purpose of a drain rooter.
A typical yard drain varies from about 12 to 18 inches deep and 12 to 18 inches wide. Four inch perforated corrugated pipe is lain in the interior. If the drain is in the yard, the gravel will be back filled to a depth of about six inches below the soil grade so the soil and grass can be planted. This drain typically discharges to the street, ravine or some other discharge point. PVC carries more water and is able to have a clean – out installed.
If the amount of water to be collected is intense during heavy rain storms i.e. the area to the side of a driveway – a collection basin may be installed.
Down spouts can also be tied into this drainage system or they can have their own discharge pipe that runs to the street or ravine.
Crawl Space Drain
Crawl space drains differ slightly. Typically crawl space drains are 8 inches wide and 8 inches deep with 4 inch corrugated pipe in the interior. It generally runs along the entire interior of the foundation and the water collects at a central point. Somtimes cross drains or “spider drains” are installed to collect water from the center of the crawl space as well. The water can be discharged by one of two ways.
The first is to have the water collect and drain into a basin. A water activated pump is placed at the bottom of this basin. As water enters the pump automatically turns on and the water is dischrged to the exterior of the home via PVC pipe. On rare occasions this pump can be tied into the municipal sewer system, but this is actually discouraged.
The other is to have the water exit the home by cutting a 4 inch hole in the exterior foundation wall and running a 4 inch discharged line to the exterior.
Ventilation Fans
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12VDC Double Fans
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Internal Dead Space Fans
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Double Unfaced Fans
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Powered Louver Fans
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Series 6, High Output
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Series 5, High Output
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