What is a French Drain?
A “French Drain” is a commonly used title for what is more generally referred to as a “Sub-Floor Drainage System” (or Pressure Relief System). The primary function of a Sub-Floor Drainage System is to remove water that would otherwise accumulate under and around the basement floor. This is the water that contributes to high basement humidity and leaks. A well designed Sub-Floor Drainage System will include a filtered perforated round pipe, stone and gravel envelope, vapor barrier and cove drainage (Hollow-Kick Mold). Understanding water table levels, existing footing size, proper positioning of pipes and the replacement of concrete are best left to experienced professionals. Pumps are often utilized in Sub-Floor Drainage Systems to expel the water that would otherwise accumulate under and around the floor.
A French drain is basically a ditch filled with gravel, rock that redirects surface and ground water away from an area. Optionally, you can improve French drain by actually using perforated piping, but the traditional gravel can be effective and is easier than installing piping. French drains are common drainage systems, primarily used to prevent ground and surface water from penetrating or damaging home foundations. French drains are also commonly used behind retaining walls to relieve ground water pressure. The earliest forms of French drains were simple ditches, pitched from a high area to a lower one filled with gravel. Lining the bottom of ditch with clay or plastic pipe increases the volume of water that can flow through the drain. Modern French drain systems can be made with perforated pipe surrounded by sand or gravel and landscaping textile. French drains can lead to dry wells or environmentally friendly rain gardens where the extra water is held and absorbed by plants. If the
The French drain is basically a trench filled with gravel. This trench is meant to keep the water runoff from a sloping piece of land to be rerouted in a productive manner. It was invented in Concord by the farmer/judge Henry French (Harvard Graduate). When surface water (such as heavy rain) is invading any given area where there is a serious drainage problem, this could be the key to recovering flooded areas. The French drain first came into the public eye in the year 1859 when Mr. French first published his book on farm drainage, in Concord, Massachusetts. The whole beauty of his idea came from careful observation. For it was not his diploma in law that showed him the ways of the land, it was his keen eye for observation and the ways of Mother Nature. He knew, like all simple farmers do, that water runs downhill, and just loves to accumulate in the most inconvenient of locations. Suffering from constant flooding, Henry French kept paying attention to water behavior until he figured o
A French drain is basically a ditch lined with rocks or gravel that helps drain water away from an area. It is generally used in gardening or to protect the foundation of a house or other structure from ground and surface water. A French drain may also be used as backup for retaining walls or to drain water away from a septic tank. A French drain works on the principle of gravity, being slightly sloped down from the area to be drained to the area where one wishes to redirect the water. It is typically lined with perforated clay pipe and surrounded with a landscaping textile to prevent dirt or plant roots from clogging the system. Excess ground and surface water percolates into the French drain and is directed away. The French drain is named after Henry French, a judge and farmer, and discussed in his 1859 book on the subject, Farm Drainage. However, the French drain predates Henry French by many centuries, as a version was used in ancient Rome. The system continues to be one of the mos
There has been a lot of confusion regarding french drains and their application. A french drain is a drainage system designed to collect subsurface drainage. A typical french drain system consists of a 4-inch diameter perforated drain pipe which is placed in a trench excavated usually 2 to 5 feet below the ground surface. The drain pipe is surrounded in 3/4 inch gravel and provided with a minimum of 12 inches of compacted fill at the top of the trench. The perforated drain pipe is either connected to a sump pump which conducts drainage to the street or is connected to solid subsurface drain pipe which drains by gravity to the street. A waterproofing membrane is also often employed to help channel subsurface drainage into the drain pipe. French drains are usually not used to correct a surface drainage problem. French drains are most effective when subsurface drainage is causing problems within underfloor areas of the residence or below grade construction. French drains are usually desig
