Drainage cost guide
French Drain Installation Cost
A basement French drain typically costs $45–$100 per ft installed for an interior perimeter drain, or $35–$100 per ft for an exterior drain at the footing. For a typical 30 × 40 ft basement, that is about $6,300–$14,000 inside or $4,900–$14,000 outside, before any new sump pump. A shallow yard drain is a different, cheaper job at $15–$40 per ft.
Planning ranges
Installed cost per linear foot
- Interior basement perimeter: $45–$100 per ft
- Exterior at the footing: $35–$100 per ft
- Shallow yard drain: $15–$40 per ft
- New sump and basin, if needed: $1,300–$2,700
Planning estimates, not quotes. Last reviewed September 22, 2026.
Start here
Which French drain are you pricing?
“French drain” names three different jobs, and most price guides blend them into one table — which is why a $2,000 quote and a $12,000 quote can both be “fair”. They sit in different places, solve different problems, and cost different amounts. Decide which one you need before comparing prices.
| Drain | Where it goes | What it fixes | Installed cost | Typical total |
|---|---|---|---|---|
| Interior perimeter drain | Under the basement floor, along the inside of the walls, into a sump | Water at the wall–floor joint, through the floor, or seeping from the base of the walls | $45–$100 per ft | $6,300–$14,000 for 140 ft |
| Exterior drain at the footing | Outside, at the base of the foundation, often with a wall membrane | Keeps water off the wall; best during new construction or when the wall itself needs sealing | $35–$100 per ft | $4,900–$14,000 for 140 ft |
| Yard (landscape) drain | A shallow gravel trench in the lawn | Soggy lawns and surface runoff — not basement leaks | $15–$40 per ft | Priced on yard French drains |
Typical totals assume the full perimeter of a 30 × 40 ft basement (about 140 ft), before a new sump pump or wall membrane. Planning estimates, not quotes.
Worked totals
What a French drain costs for your basement
Per-foot prices are only useful once you know the footage. These are the totals for common scopes — from one problem wall to the full perimeter — using the same per-foot ranges.
| Scope | Length | Interior drain | Interior + new sump | Exterior drain |
|---|---|---|---|---|
| One problem wall | 30 ft | $1,350–$3,000 | $2,650–$5,700 | $1,050–$3,000 |
| Two walls | 70 ft | $3,150–$7,000 | $4,450–$9,700 | $2,450–$7,000 |
| Full perimeter, 30 × 40 ft basement | 140 ft | $6,300–$14,000 | $7,600–$16,700 | $4,900–$14,000 |
| Full perimeter, 40 × 50 ft basement | 180 ft | $8,100–$18,000 | $9,400–$20,700 | $6,300–$18,000 |
New sump pump and basin: $1,300–$2,700; tying into a working existing sump: $0–$600. Exterior totals exclude a wall membrane, which adds $10–$30 per ft.
A partial system along one or two walls is common and legitimate when water only enters there — but it should be a decision based on where the water shows up, not a way to shrink the quote. For your own footage, finish and access, the French drain cost calculator uses the same figures.
Decide
Interior or exterior: what each one does and doesn't do
| Interior perimeter drain | Exterior drain at the footing | |
|---|---|---|
| Typical cost, 140 ft | $7,600–$16,700 with a new sump | $6,300–$18,200 with a wall membrane |
| How it works | Collects water that reaches the footing and slab, and pumps it out | Intercepts water outside before it reaches the wall |
| Does the wall stay dry? | Not necessarily — water can still reach the wall; the drain removes it at the bottom | Yes, when paired with a membrane on the wall |
| Disruption | Inside: a strip of floor is cut and re-poured; finished walls may be opened | Outside: excavation to the footing, landscaping and walkways disturbed |
| Needs a sump pump? | Almost always | Often drains by gravity to daylight; sometimes to a sump |
| Best for | Existing homes with water at the wall–floor joint or through the floor | New construction, or when the wall itself is leaking or deteriorating |
| Not the answer when | The water comes from gutters, grading or one crack | Access is blocked by patios, driveways or neighbors |
For the wider trade-off, see interior vs exterior basement waterproofing and sump pump vs French drain.
Before you pay for any drain
When a French drain is the wrong fix
A drainage system is expensive and permanent. It is worth ruling out the cheaper causes first, because a surprising share of basement water starts outside the house:
- Gutters and downspouts discharging at the foundation. A 2,000 sq ft roof sheds over 1,200 gallons in an inch of rain.
- Soil that slopes toward the house instead of away from it.
- A single leaking crack. See sealing a leaking foundation crack.
- Condensation rather than water entry — see basement humidity.
Not sure which you have? Find the source of the water or use the water source diagnostic.
The invoice
What's in an interior French drain quote
| Line item | Planning range | Notes |
|---|---|---|
| Cutting and removing the floor strip | Included per foot | Typically a 12-inch strip along the walls |
| Trenching, stone and perforated pipe | Included per foot | Pipe set in clean stone, sloped to the sump |
| Concrete re-pour | Included per foot | The floor strip is patched after the pipe is set |
| Wall dimple membrane | $3–$8 per ft | Directs wall seepage down into the drain |
| Opening and rebuilding finished walls | $15–$40 per ft | Only where walls are finished |
| New sump pump and basin | $1,300–$2,700 | If there is no usable sump |
| Sump with battery backup | $2,200–$4,200 | Recommended for finished basements |
| Discharge line | $0–$400 to $600–$1,800 | Longer runs, burial and restoration cost more |
| Cleanouts or inspection ports | Often included | Ask for them — they make future maintenance possible |
Exterior
What's in an exterior French drain quote
| Line item | Planning range | Notes |
|---|---|---|
| Excavation to the footing | Included per foot | Depth drives the cost more than length |
| Perforated pipe, filter fabric and stone | Included per foot | Wrapped pipe resists silting |
| Wall cleaning and membrane | $10–$30 per ft | Keeps water off the wall itself |
| Backfill and compaction | Included per foot | Clean stone near the wall, soil above |
| Outlet to daylight or a sump | $0–$400–$900–$3,000 | Gravity to daylight where the lot allows |
| Landscape and hardscape restoration | $5–$25 per ft | Plants, lawn, walkways, patios |
Upkeep
How long a French drain lasts, and what it costs to keep working
| Item | Planning figure | Notes |
|---|---|---|
| Drain lifespan | Decades, if installed with cleanouts | Silt and iron ochre are what clog them |
| Flushing the lines | $150–$400 per service | Only possible if cleanouts were installed |
| Sump pump replacement | $350–$1,000 | Interior drains depend on the pump; plan for a new one every 7–10 years |
| Battery backup battery | $150–$250 every 3–5 years | Recommended for finished basements |
| Annual check | $0 DIY | Pour water at the far end of the drain and watch the sump |
Planning figures, not quotes.
Iron-rich groundwater can leave an orange, gelatinous ochre that coats the pipe. If your sump water runs orange, ask about wider pipe, more cleanouts and a flushing schedule before the system goes in.
Region
French drain cost by region
| Region | Versus the national range | Why |
|---|---|---|
| Northeast and Mid-Atlantic | 10–25% higher | Higher labor rates; older foundations |
| Midwest | About average | Basements common; competitive market |
| Southeast | About average or slightly lower | Clay soils add digging time outside |
| Mountain West | About average to 20% higher | Rocky ground, deeper frost |
| Pacific Northwest and California | 15–30% higher | Highest labor rates |
Regional adjustments are planning estimates; access, depth and finish level move the price more than region.
Price drivers
What drives French drain cost up
| Factor | Effect | Why |
|---|---|---|
| Finished basement | +10–25% | Drywall, flooring and trim removed and restored |
| Tight access, utilities, hardscape | +15–25% | Slower work and more protection |
| Rocky or heavy clay soil (exterior) | +10–25% | Harder digging and more disposal |
| Depth to the footing (exterior) | Major | Deeper excavation, shoring and backfill |
| No usable sump | $1,300–$2,700 | New basin, pump and discharge |
| Long or buried discharge | $600–$1,800 | Trenching and yard restoration |
| Landscape restoration (exterior) | $5–$25 per ft | Plantings, lawn, walkways |
Quote check
What a fair French drain quote spells out
- Which drain — interior perimeter, exterior footing, or yard — and why.
- The exact footage and which walls, marked on a sketch.
- Pipe type and stone, and how the pipe slopes to the sump.
- The sump plan: tie into the existing one, or a new basin and pump (with brand and model).
- Where the water discharges outside.
- Cleanouts, and a wall membrane if one is proposed.
- What is restored — floor, finished walls, landscaping — and what isn't.
- Warranty terms, including whether they transfer to a buyer.
Compare quotes line by line with the quote analyzer or the checklist in is my basement waterproofing quote fair?.
DIY or pro
Can you install a basement French drain yourself?
A shallow yard drain is a weekend DIY project. An interior basement drain is a different scale: cutting a concrete strip around the whole perimeter with a wet saw, breaking and hauling out several tons of concrete, trenching to the right depth with a consistent slope to a sump, setting pipe and stone, and re-pouring. It is possible with rented equipment, but mistakes end up buried under new concrete, and a sump plus discharge still has to be done properly. Most homeowners hire it out and spend their effort getting the scope right.
Next step
Estimate your drain
FAQs
French drain cost questions
How much does it cost to install 100 ft of French drain?
It depends on which drain. An interior basement perimeter drain runs roughly $4,500–$10,000 for 100 ft, an exterior drain at the footing $3,500–$10,000, and a shallow yard drain $1,500–$4,000. A new sump pump and basin, if the drain needs one, adds $1,300–$2,700.
Is an interior or exterior French drain cheaper?
Per foot they overlap, but an interior drain is usually the lower total for an existing home because it avoids excavating around the foundation, moving landscaping and restoring the yard. An exterior drain costs more to reach but keeps water off the wall entirely, especially when paired with a wall membrane.
Are French drains worth the money?
When water is entering at the wall–floor joint or rising through the floor, an interior perimeter drain with a sump is one of the most reliable fixes available. It is not worth it when the water comes from something cheaper to fix — gutters and downspouts dumping at the foundation, a grade that slopes toward the house, or a single leaking crack.
Does an interior French drain need a sump pump?
Almost always. An interior drain sits below the basement floor, so the water it collects has nowhere to drain by gravity; it runs to a sump basin and is pumped out. If you already have a working sump, the drain can often tie into it.
Can I install a French drain myself?
A shallow yard drain is a common DIY project. An interior basement drain means cutting and breaking out a strip of concrete floor around the perimeter, trenching, setting pipe and stone, installing or tying into a sump, and re-pouring. It is possible with rented equipment but is heavy, dusty work, and mistakes are buried under concrete.
How long does a basement French drain last?
A properly installed interior drain can last decades. What shortens its life is silt and iron ochre clogging the pipe, a failed sump pump, and installations with no cleanout or inspection port. Ask for cleanouts in the quote.
What are the alternatives to a French drain?
Depending on where the water comes from: gutter and downspout fixes, regrading the soil so it falls away from the house, sealing a single crack, or a sump pump alone for a high water table. Paint-on sealers do not stop water under pressure.
Does homeowners insurance cover French drain installation?
No — it is a waterproofing improvement. Some water damage that prompted it may be covered depending on the cause and your policy, so check with your insurer separately.
Glossary
Terms on a French drain quote
| Term | Meaning |
|---|---|
| Interior perimeter drain | Perforated pipe in stone under the basement floor along the walls, feeding a sump. |
| Footing drain | A drain at the base of the foundation footing, usually on the outside. |
| Drain tile | The trade term for perforated drain pipe, from the clay tiles once used. |
| Wall–floor (cove) joint | The seam where the basement wall meets the floor; the most common entry point. |
| Dimple membrane | A plastic sheet on the inside of the wall that channels seepage down into the drain. |
| Sump basin | The pit the drain empties into, where a pump lifts the water out. |
| Cleanout | An access port that lets the drain pipe be flushed or inspected later. |
| Discharge line | The pipe carrying pumped water outside and away from the house. |
Related pages
Where to go next
Sources
Sources
Figures are planning ranges drawn from national cost guides and contractor pricing, reviewed September 22, 2026. They are not quotes; local labor, access and site conditions vary.