Installing a French drain is an effective method to divert water from getting into your crawlspace or basement. It involves placing a French Drain along your foundation footer.

Tools and Materials

Before we begin, let's gather all the necessary tools and materials.


  • Trench shovel


  • Non-woven Landscape fabric
  • 4" Perforated Drain Pipe
  • Round River rock

Step 1: Dig the Trench

Dig a 6" to 12" wide trench along the foundation wall. If you do it in sections, this will reduce the chance of undermining the foundation wall. It is recommended to dig 12" - 24" deep so that you are at or near the bottom of the foundation footer. These variances in the trench width and depth are due to the local area codes that require different depths depending on the soil and frost line.


Step 2: Compact the Soil

Compact any loose soil in the bottom of the trench. Either use a hand compactor or a 6-foot 4x4.

Step 3: Insert Landscape Fabric

Put unwoven landscape fabric in the trench to form a burrito. I used 6' wide fabric so it would extend up a few feet on each side.

Step 4: Add the First Layer of Rocks

Install a 2 or 3-inch layer of round rock on top of the fabric.

Rock Layer

Step 5: Lay the Drain Pipe

Lay the 3" or 4” diameter perforated drain pipe on top of the round rock. The holes need to face DOWN.

Drain Pipe

Step 6: Add the Second Layer of Rocks

Put in another 2"-3" of round rock on top of the drain pipe.

Step 7: Wrap the Fabric

Wrap the fabric so it covers the rock.

Step 8: Add the Final Layer of Rocks

Add 2"-3" of round rock on top of the fabric. Alternatively, it can be covered with sod or other topsoil.