The purpose of a French Drainage System is to carry unwanted free standing water away from a building, such as your home. French drains are commonly installed near the perimeter of a building at the lowest point or anywhere where standing water is found. Or a French drain may begin in the basement crawlspace. And the system may terminate at any point where the water will not drain back toward the house.

French drains are generally shallow drainage systems. However, as with your plumbing waste drainage, French drains operate on the principle of gravity. The drain must slope downward. If the landscape grade runs upward along the French drain path you will have to dig deeper to maintain a downward slope.

There are many variables that affect how individual houses develop water problems. Often it is a combination of factors that develop over time. French drains work by curing a symptom, not the cause. They extract the water collected in the drainage pipes to the outside. In some instances, inside French drains are used to channel water away from the house.