French Drain Installation Cost Calculator
How much does a french drain cost to install? $10 to $100 per linear foot — but that tenfold spread is not vagueness. A french drain is really five different jobs (yard, curtain, exterior footing, interior basement, crawl space), and which one you need decides almost everything about the price. This calculator prices all five, then adds the real-world extras contractors actually bill: depth, soil type, sump pump, concrete breakout, permits, obstructions, discharge, and landscape restoration.
Estimate your project
How the estimate works
Contractors price french drains mostly by the linear foot, but the rate already bakes in depth, labor, and site difficulty. The engine below mirrors that logic: pick the system type, and the calculator layers on the same adjustments real bids use.
Estimate formula
per-foot rate = type base + depth adder, then adjusted for soil (labor is ~60% of installed cost: clay ×1.2 labor, rocky ×1.4 labor).total = (linear ft × per-foot rate) + sump + concrete + permit + obstructions + discharge + restorationDepth is the single biggest driver. A shallow exterior drain under two feet runs $10 to $35 a foot; the same trench taken down to the footings runs $30 to $90 — you are paying for cubic yards of excavation, not for pipe. Interior basement drains cost the most per foot ($40 to $100) because the concrete floor must be cut, debris hauled out, and new concrete poured. Nationally, Manta reports homeowners spend about $4,829 per french drain project on average, with most projects landing between $1,254 and $8,405 — right in the middle of the bands this calculator produces.
Cost per linear foot by drain type (2026)
| Drain type | Installed $/ft | Typical depth | Best for |
|---|---|---|---|
| Yard / surface drain | $10 – $35 | 12–18 in | Soggy lawn, surface water |
| Curtain drain | $10 – $25 | 12–24 in | Intercepting water uphill of the house |
| Exterior footing drain | $30 – $90 | 3–6 ft (to footing) | Foundation waterproofing, new/existing homes |
| Interior basement perimeter | $40 – $100 | Below slab | Hydrostatic pressure, chronic basement flooding |
| Crawl space drain | $20 – $40 | Below grade | Damp crawl spaces |
Common cost adders
| Adder | Typical cost | Notes |
|---|---|---|
| Deep trench (6–8 ft) | +$15 – $30 /ft | Heavy machinery required |
| Clay / rocky soil | +20 – 40% of labor | Slower digging, special equipment |
| Sump pump + pit | $800 – $2,500 | Required for most interior systems |
| Battery backup sump | $2,500 – $4,500 total | Premium system incl. backup |
| Concrete breakout + haul | $500 – $1,000 | Interior basement jobs |
| Permit | $50 – $200 | Varies by municipality |
| Obstruction (each) | $500 – $2,000 | Driveway, patio, utility crossing |
| Dry well / bubbler pot | $550 – $850 | When there is no slope to daylight |
| Extra discharge line | $3 – $8 /ft | Long runs to a safe outlet |
| Landscape restoration | $200 – $1,000 basic; 15–30% full | Often billed separately |
| Wall vapor barrier | $1,500 – $1,800 | ~1,000 sq ft basement, interior systems |
Worked examples (step by step)
Example 1 — 80 ft yard drain in clay soil, with permit and basic restoration
- Base rate: yard drain $10–$35/ft; shallow depth adds $0 → $10–$35/ft.
- Soil adjustment: clay multiplies the labor share (60%) by 1.2 → effective rate $11.20–$39.20/ft.
- Drain cost: 80 ft × rate = $896–$3,136.
- Adders: permit $50–$200 + basic restoration $200–$1,000 = $250–$1,200.
- Total: $1,146 – $4,336.
Example 2 — 100 ft interior basement perimeter drain, full setup
- Base rate: interior basement $40–$100/ft → 100 ft = $4,000–$10,000.
- Adders: standard sump $800–$2,500 + concrete breakout $500–$1,000 + vapor barrier $1,500–$1,800 + permit $50–$200.
- Total: $6,850 – $15,500.
- Bundle check: a full waterproofing package for an average home runs $6,500–$13,500 — compare before you sign.
Example 3 — 60 ft exterior footing drain, deep trench, rocky soil, one obstruction, dry well
- Base rate: exterior footing $30–$90/ft + deep (5–8 ft) adder $15–$30/ft → $45–$120/ft.
- Soil adjustment: rocky multiplies the labor share (60%) by 1.4 → effective rate $55.80–$148.80/ft.
- Drain cost: 60 ft × rate = $3,348–$8,928.
- Adders: one obstruction $500–$2,000 + dry well $550–$850 = $1,050–$2,850.
- Total: $4,398 – $11,778.
DIY vs hiring a pro
| DIY (yard drain) | Professional | |
|---|---|---|
| Materials (80 ft yard drain) | $470 – $1,100 | included in per-foot rate |
| Installed (80 ft yard drain) | n/a | $800 – $2,800 |
| Savings | Roughly 56% — but only your labor is free | |
| Best for | Shallow yard / curtain drains | Interior, deep, or footing-depth work |
DIY materials for a shallow drain run about $4–$10 per foot (perforated pipe $1–$5/ft, gravel $30–$60/ton, fabric $0.15–$0.60/sq ft) plus $150–$300 for a trencher rental. The catch is grading: a french drain that is not pitched correctly just moves the puddle. Interior and deep-footing drains are pro-only work — concrete cutting, structural footings, and cave-in risk are not DIY territory.
Practical tips before you get quotes
- Get three written bids — and make them itemized. Ask each contractor to break out per-foot rate, depth, sump, permit, and restoration separately. Restoration (15–30% of the job) is the line most often "forgotten" until the end.
- Match the system to the water source. Surface puddles → yard or curtain drain. Water seeping through basement walls → exterior footing drain. Water pushing up through the slab → interior perimeter drain with a sump pump. The wrong system is the most expensive mistake.
- Check the outlet first. A drain with nowhere to go is a buried bathtub. If your lot has no slope to daylight, budget a dry well ($550–$850) or a sump discharge plan before the trench is dug.
- Ask about the fabric and the pitch. Geotextile fabric around the gravel keeps soil from clogging the system; 1% minimum slope keeps water moving. Both are cheap at install time and expensive to fix later.
- Time it with other yard work. If you are already regrading, re-sodding, or replacing a driveway, bundle the drain — one mobilization, one restoration bill.
- Photograph everything before backfill. Pipe, gravel depth, fabric wrap, and the outlet location. Future-you (or a future buyer) will thank you.
Frequently asked questions
How much does a french drain cost per linear foot?
Installed cost runs $10 to $35 per linear foot for a shallow yard drain, $10 to $25 for a curtain drain, $30 to $90 for an exterior drain excavated to the foundation footing, $40 to $100 for an interior basement perimeter drain, and $20 to $40 for a crawl space drain. The spread exists because a french drain is really five different jobs: depth, soil, and whether concrete has to be broken decide the price far more than pipe or gravel.
Is an interior or exterior french drain cheaper?
Interior basement drains ($40 to $100 per foot) usually cost more per foot than exterior footing drains ($30 to $90 per foot), because the crew must jackhammer the slab, haul debris out, and re-pour concrete. Shallow yard drains are cheapest at $10 to $35 per foot. Use the calculator above to compare both options for your linear footage.
How much does a 100-foot french drain cost?
A 100-foot yard drain costs roughly $1,000 to $3,500 installed. The same 100 feet as an interior basement perimeter drain runs $4,000 to $10,000 before the sump pump, concrete breakout, and permit are added. Add a standard sump pump ($800 to $2,500) and concrete removal ($500 to $1,000) for a realistic interior total.
Does a french drain need a sump pump?
Interior systems almost always need one, because the drain sits below grade with nowhere to gravity-drain. Budget $800 to $2,500 installed for a basic pit and submersible pump, or $2,500 to $4,500 for a premium system with battery backup. Exterior and yard drains can often discharge by gravity for free if the lot has slope.
How deep should a french drain be, and what does depth add?
Yard drains are typically 12 to 18 inches deep. Exterior foundation drains go to the footing, usually 3 to 6 feet. Taking a trench down to 6 to 8 feet needs heavy machinery and adds roughly $15 to $30 per linear foot. Depth is the single biggest cost driver: you are paying for cubic yards of excavation, not for pipe.
How does soil type change the cost?
Digging through clay or rocky soil adds about 20 to 40 percent to labor costs, because the crew works slower and may need specialized equipment. On a typical project where labor is around 60 percent of the total, clay soil raises the bill roughly 12 percent and rocky soil roughly 24 percent versus easy sandy loam. Select your soil in the calculator to see the effect.
Do I need a permit to install a french drain?
It depends on your municipality, especially for exterior drains near property lines or work that changes drainage patterns. Where required, permit fees usually run $50 to $200. Call your local building department before digging, and always have utilities marked.
How long does french drain installation take?
A shallow yard drain in an accessible yard can be done in about a day. An interior basement perimeter system typically takes 1 to 2 days. A deep exterior footing drain around an existing home can take 5 to 7 days because of the excavation, weather exposure, and restoration work.
Is it cheaper to install a french drain myself?
For a shallow yard drain, DIY materials run roughly $4 to $10 per linear foot (pipe, gravel, fabric) plus $150 to $300 for a trencher rental, so an 80-foot drain costs about $470 to $1,100 in materials versus $800 to $2,800 professionally installed. DIY is not recommended for interior or deep-footing drains, which need concrete cutting, structural care, and proper grading.
What does landscape restoration cost after a french drain?
Basic restoration (regrading and re-sodding the trench line) typically costs $200 to $1,000. Full restoration of lawns, mulch beds, and paver or patio resets usually runs 15 to 30 percent of the drain subtotal and is often billed separately from the drain quote, so ask whether your bid includes it.
What is a curtain drain, and when is it enough?
A curtain drain is a shallow french drain ($10 to $25 per foot) placed uphill of the problem area to intercept surface and subsurface water before it reaches the house. It is enough for soggy yards and mild seepage. It will not fix hydrostatic pressure pushing water up through a basement slab; that needs an interior perimeter drain with a sump pump.
French drain vs full basement waterproofing package: which should I buy?
A drain-only interior system handles water already at the slab. A full waterproofing package (perimeter drain, sump pump, battery backup, wall vapor barrier, warranty) typically runs $6,500 to $13,500 for an average home. If walls leak or you are finishing the basement, the package is usually the better value; for a simple wet corner, the drain alone may be enough. The calculator's bundle check compares both bands.
Related tools
Free tool by NRTechStudio