Licensed & Insured. Air Duct Cleaning Specialists 615-371-5355

Need Help Now? Call 615-371-5355

Crawlspace French Drain

Many people suffer from allergies and excessive dust and particulates in the air and need to do something to improve their indoor air quality. We can help.

French Drains To Manage Water

What makes french drains french? Did the French invent the drainage solution? What about drain tiles? Aren’t they made with corrugated plastic pipe or PVC? The truth is, these are no more French than English or Spanish drains. Henry Flagg French transformed drainage water management from a downwards sloping trench filled with gravel to the use of clay, half circle roofing tiles formed into a pipe with a ⅛ inch gap between the tiles buried in gravel to allow water to travel downhill without causing erosion. Other names they are known by is French ditch, perimeter drain, sub-soil drain, rock drain or agricultural drain.

Modern French drains are made with 4” corrugated plastic or PVC pipe. They are covered with a mesh filter fabric that allows the water to enter but filters out the soil. They are buried in gravel or foam pellets to allow the water to follow the path of least resistance to the pipe. A new “all in one” French Drain has been developed by NDS called the EZ-Drain. Tier use’s this one when there is no danger of crushing, otherwise, we recommend PVC with holes in the bottom, wrapped in a filter fabric sock, surrounded by gravel.

Professional French Drain Installation

French Drains are designed to absorb surface water or to absorb underground water from a rising water table, or both, as in the case of a perimeter drain. A perimeter drain should be installed at the bottom of the footer, below the waterproofed foundation wall to collect water that would otherwise enter the basement or crawlspace. Many perimeter drains and waterproofed foundation wall systems fail over time or were never properly installed. The best way to fix it is to dig the dirt away from the foundation wall and start over with new waterproofing membrane and coating for the wall and new French Drain, then backfill with gravel and dirt as necessary.

Interior or Exterior French Drains

A “downstream” approach is to install a French Drain on the inside of the basement or crawlspace while installing a membrane on the inside wall of the basement to allow the water seeping inside to run down to the drain. The downside to interior French Drains is that erosion can occur over time and possibly create a problem for the foundation. However, sometimes the cost and disruption of the exterior waterproofing solution make the risk of an interior drain more preferable.

A rising water table is managed only by a French Drain and sump pump system. The water is collected in the French drain as it rises and then pumped away by the sump pump. A curtain drain is a variation on the French Drain. A series of french drains are installed diagonally across a hill, from top to bottom so surface water is collected into the French drains and directed to a drain on the side thereby preventing erosion on the hill.

For a professional water management plan, call Tier at 615-371-5355.

Divisions of Tier

We can tackle most any problem you may encounter in the environmental restoration industry!

Service Areas