French Drain Installation

What is french drain?

A French drain is a perforated drainpipe in a gravel-filled trench that channels water away from your foundation and crawl space. Two variants exist: interior French drain (installed inside the crawl space perimeter, routed to a sump) and exterior French drain (installed outside the foundation, routed to daylight or a separate drainage point). Both protect crawl spaces from chronic water intrusion.

Why you need it

• Stops chronic water intrusion at the source (the foundation perimeter)
• Reduces hydrostatic pressure on foundation walls
• Required for hillside lots, high water tables, and crawl spaces with active seepage
• Pairs with sump pump as the complete water management system

Our process

1. Site assessment. Identify water source: groundwater, surface runoff, hillside drainage, downspout discharge. Determines interior vs exterior approach.
2. Excavation. Dig trench along the affected perimeter to below the slab or footing level.
3. Gravel base and pipe. Lay filter fabric, place gravel base, set perforated drainpipe, cover with more gravel.
4. Outlet routing. Connect to sump basin (interior) or daylight outlet (exterior).
5. Backfill and restore. Cover with gravel and original surface material. Verify proper grade away from foundation.

Cost range

$2,000 – $6,500

Interior drains at the lower end, exterior drains higher due to excavation. Linear footage and depth are the main cost drivers.

Where we serve

Available statewide. Fastest response in our primary Tennessee metros: