Installing a French drain behind a wall

A French drain, also known as a rubble drain, is a trench filled with gravel or rock that is designed to redirect surface water or groundwater away from an area. The drain consists of a perforated pipe that is surrounded by gravel or rock and is typically covered with a geotextile fabric to prevent sediment from clogging the drain.

To install a French drain behind a wall, you will need to follow these steps:

1. Determine the location and depth of the French drain: The location of the drain should be such that it collects water from the area that needs drainage. The depth of the drain should be such that it allows for proper drainage of the water.
2. Dig the trench: Once you have determined the location and depth of the drain, dig a trench that is wide enough to accommodate the perforated pipe and the gravel or rock. The trench should be sloped away from the wall to allow water to flow away from it.
3. Install the geotextile fabric: Line the trench with geotextile fabric, ensuring that it extends beyond the edges of the trench.
4. Add the gravel or rock: Fill the trench with gravel or rock, ensuring that it covers the perforated pipe.
5. Install the perforated pipe: Place the perforated pipe in the center of the trench on top of the gravel or rock.
6. Cover with more gravel or rock: Cover the perforated pipe with more gravel or rock until the trench is filled to the top.
7. Cover with geotextile fabric: Fold the geotextile fabric over the top of the trench and cover it with soil or other landscaping material.
8. Test the drain: Test the drain by pouring water into the trench and ensure that the water flows away from the wall.

By following these steps, you can effectively install a French drain behind a wall to redirect water away from the area.