French Drains: How They Protect Foundations
A French drain is a simple, powerful tool for foundation protection: a gravel-and-pipe channel that intercepts water before it reaches your slab.
How it works
A perforated pipe in a gravel trench collects subsurface and surface water and carries it to a safe outfall, relieving the hydrostatic pressure that swells clay at the slab edge.
When you need one
Persistent wet zones, water sheeting toward the house, or a yard that slopes inward are classic cases — part of a broader drainage plan.
Part of the system
French drains work best alongside grading and downspout control, and pair with stabilization where movement has occurred. Common across low-lying Cibolo.
- A French drain intercepts water before the slab.
- Use one for persistent wet zones or inward slope.
- It works best within a full drainage plan.
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