How Do You Install a French Drain?

Installing a French drain requires digging a sloped ditch, lining it with landscaping fabric, adding gravel, laying perforated pipe, adding more gravel up to grade to increase the drainage and covering the trench. The process takes up to a day to complete, depending on the drain size.

  1. Dig the trench

    Determine where to put the French drain, then dig a trench approximately 2 feet wide and 2 feet deep. Clear away roots and rocks. Slope the bottom of the trench to direct the water away from important structures.

  2. Line and fill the trench

    Place landscaping fabric over the trench. If needed, cut the landscaping fabric to fit into the trench, making sure that the fabric covers the sides. Pour enough gravel to cover half the depth of the trench. Be mindful of the slope while pouring the gravel, as it can complicate the pouring process.

  3. Lay the perforated pipe

    Place the perforated pipe into the trench with the drainage holes facing down, making sure that the pipe is sloped.

  4. Cover the trench

    Pour more gravel over the pipe to increase drainage. If there is landscaping fabric sticking up from the sides of the trench, wrap it over the gravel. Add more gravel or decorative stones to hold the fabric in place or use topsoil to blend the French drain into the landscape.