French/Perimeter Drain

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French Drain, Damp Proofing Specialist Contractor in Johannesburg, Pretoria and Cape Town


French drain or weeping tile (also blind drainrubble drain, rock drain, drain tileperimeter drainland drainFrench ditchsub-surface drainsub-soil drain or agricultural drain) is a trench filled with gravel or rock or containing a perforated pipe that redirects surface water and groundwater away from an area. A French drain can have perforated hollow pipes along the bottom to quickly vent water that seeps down through the upper gravel or rock.

French drains are primarily used to prevent ground and surface water from penetrating or damaging building foundations.

Water always flows downhill, and by the easiest route possible. That’s the basic concept behind a French drain, a slightly sloped trench filled with round gravel and a pipe that diverts water away from your house. By the way, the name doesn’t come from the country. It’s from Henry French, a judge and farmer in Concord, Massachusetts, who promoted the idea in an 1859 book about farm drainage.

How a French Drain Works

French drains provide an easy channel for water to flow through. Water runs into a gravel-filled trench, then into perforated pipe at the bottom of the trench. Water travels freely through the pipe, which empties a safe distance from the house. The trench bottom should be sloped about 1 inch for every 8 feet in the direction you want water to flow. Depending on your situation, the water can be diverted to:

  • A low-lying area of your property
  • A drainage ditch
  • A dry well
  • The street

When You Need a French Drain

  • When you have a problem with surface water, such as a soggy lawn or a driveway that washes out
  • If water is getting into your basement
  • If you’re building a retaining wall on a hillside

If Your Problem is Surface Water Install a shallow French drain. Also called a curtain drain, it extends horizontally across your property, directly uphill of the area you want to dry out. It intercepts water and channels it around the soggy spot. This type of drain doesn’t have to be very deep — a common size is 2 feet deep and 1.5 feet across. Where the drain passes through areas with trees or shrubs, switch to solid pipe (not perforated) to reduce the risk of roots growing into the piping and clogging it.

SA Damp, an established damp proofing specialist in Johannesburg and Pretoria, provides premium quality damp proofing solutions in Johannesburg and the Pretoria area to the residential, industrial and commercial property sectors.

Our quality damp proofing materials, exceptional standards of service and professional team will guarantee that you receive the high standard of workmanship that you expect from a damp proofing specialist contractor.

We use the best products on the market along with over 20 years of experience. We have a close working relationship with our suppliers including, XYPEX and STONCOR.

Contact us today for a FREE professional consultation.

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Call us now on 011 467 7600 | 011 791 0925

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