French Drain Systems

French drain systems will help fix water problems around and inside your home’s foundation or crawl space.

Constant sources of water and moisture in and around your home are its worst enemies. These conditions lead to mold, fungus and eventually rot.

Water always flows down hill and seeks the lowest level. This is caused by the Earth’s gravity. We have all seen this happen every time we are around water in streams, rivers, ponds, lakes, puddles, rain-storms, ditches, etc.

In the mid 1800’s Henry French wrote a book about controlling water with drainage; hence the name French drain.

The basic concepts of french drain systems are:

Water flows downhill by the easiest route possible.
A slightly sloped trench filled with gravel and a pipe at the bottom will divert water away from a house, structure, low lying area, etc.

If you apply this to your home you can see how water flows toward your foundation or crawl space when:

Your home is built in an area that is lower than part or all of your surrounding yard.
Water from your roof and/or downspouts puddles against your foundation after it rains.
Water flows towards your home from sidewalks, driveways or streets.
Water will seep into your crawlspace if it’s lower than the area immediately surrounding your home by drainage. Groundwater also wicks under and through your foundation. Water will flow even faster if your home is also lower than the surrounding area. This outer area will “funnel” the water into your crawlspace.
Your septic field is slightly higher in your yard than your foundation.
Lower areas in your yard nearby are always soggy.
Condensation lines from your heating and cooling systems discharge next to your foundation.
Sprinkler/water systems are next to your home.

French Drain Systems will assist in creating a path for water before it gets into your crawl space.

The grade that water follows above and under the dirt toward your home can be very slight. The water is going to eventually go where natural force takes it.

Once the waters get around your foundation they wick through cinder block, brick, mortar, cement and wood. You can see the telltale white hazy lines of minerals caught/strained from the water as it passes through those construction materials.

In your crawl space, the water turns into water vapor and is sucked into the wood, insulation and eventually up into your living area.

Do your air conditioners run constantly on hot, humid days? Think of your crawl space as a cool area where moist hot air comes from the outside into contact with everything inside. The water condenses out of that air like water forming on the outside of an iced drink in humid air. (This is also the basic concept of air conditioning).

To begin to fix these moisture problems you need to stop the water from getting into the crawlspace by:

Digging and installing a French drain system around the exterior to divert large amounts of water if there is no other way to divert those flows.
Dig and install a French drain system around the interior base of the crawl space wall to catch and expel the water. If the crawl space is lower than the exterior you will need a sump pump to push the collected drain water up, out and away from your homes’ foundation.
You will also need some type of ground vapor barrier to capture the water vapor moisture coming out of the ground. That water will eventually get to the lower French drain around the crawl space perimeter.