The drain type matters most
A shallow yard drain, an exterior foundation drain, and an interior basement perimeter drain can all be called French drains, but the labor and purpose are different.
Cost calculator
French Drain Cost Calculator
Estimate a planning range for French drain installation by drain type, linear footage, basement access, soil conditions, sump pump needs, discharge route, and project complexity.
Use the result wisely
What the estimate includes
- Interior, exterior foundation, yard, and unsure drain scopes.
- Linear footage, access, soil, sump, discharge, and location adjustments.
- A broad planning range for comparing quotes, not a guaranteed price.
- Questions to ask before accepting a drainage estimate.
Drainage work may involve utilities, easements, property lines, stormwater rules, finished materials, and safety concerns that require on-site review.
Cost calculator
Estimate French drain cost by scope
Choose the closest project details. The result is a planning range for comparing estimates, not a quote or diagnosis.
Many targeted projects are 40-80 feet. Full basement perimeters often land closer to 100-160 feet.
Compare the full scope
Ask whether the quote includes concrete repair, stone, pipe, fabric, sump connection, discharge routing, cleanup, and surface restoration.
Check drainage limits
Exterior discharge may need review when slope, property lines, easements, stormwater infrastructure, or public runoff are involved.
Cost guide
French drain cost by project type
The calculator uses broad planning assumptions from current cost guides, then adjusts for length, access, soil, sump equipment, discharge route, and finish level. Local quotes can land outside these ranges.
| Type | Planning range | Best fit |
|---|---|---|
| Yard/surface drain | $20-$50/ft | Surface runoff, soggy lawn, downspout water |
| Exterior foundation drain | $35-$100/ft | Water near the foundation, exterior excavation, footing-level drainage |
| Interior basement drain | $65-$125/ft | Wall-floor joint seepage, floor seepage, sump-connected systems |
Quote checklist
Questions to ask before accepting a French drain estimate
- Is this an interior basement drain, exterior foundation drain, or yard drainage project?
- How many linear feet are included, and how was that footage measured?
- Where will collected water discharge, and is that outlet allowed for this property?
- Is a sump pump, basin, alarm, or battery backup included?
- What concrete, flooring, landscaping, hardscape, or cleanup work is excluded?
- What happens if roots, utilities, clay, rock, or poor slope are discovered?
When a French drain may not be the first fix
If water appears during dry weather, starts near a water heater or appliance, smells like sewage, or involves electrical risk, waterproofing may not be the first call. Rule out plumbing, mechanical, cleanup, and safety concerns before comparing drainage systems.
Questions homeowners ask
French drain calculator FAQs
How much does a French drain cost per foot?
The cost per foot depends on whether the project is a shallow yard drain, an exterior foundation drain, or an interior basement perimeter drain. Interior basement systems usually cost more because they may include concrete cutting, floor repair, and sump connection.
Do I need a sump pump with a French drain?
Many interior basement French drains need a sump pump because collected water has to be removed from the basement. Some yard or exterior drains can discharge by gravity if the property has a suitable outlet.
Why are French drain quotes so different?
Quotes can differ because one contractor may include only trenching and pipe, while another includes concrete work, sump equipment, discharge routing, restoration, utility concerns, and drainage review.
Is an exterior French drain better than an interior drain?
Not automatically. Exterior drains can reduce water before it reaches the wall, while interior systems manage water after it enters. The better fit depends on the water source, access, basement finish, budget, and discharge route.
Can this calculator replace an inspection?
No. The result is a planning range. A contractor still needs to inspect water source, slope, utilities, access, soil, discharge options, and safety concerns.