French Drain Cost Calculator
“French drain” is one name for five different jobs, and the price spread between them is tenfold: $10 per foot for a shallow yard trench, up to $100 per foot for an interior basement perimeter that requires breaking concrete. Online estimates that quote a single number are useless until you know which job you are pricing, which is exactly what this calculator asks first.
Pick the drain type that matches your water problem, enter the length, add a sump pump if the design needs one, and the tool returns a low-to-high installed range, the per-foot math behind it, and an honest DIY materials comparison. Because drainage starts at the roofline, it is worth checking how your gutters feed the system too: our guttering cost per foot calculator prices that side of the water’s journey.
French Drain Cost Calculator
Quick Answer
Quick answer: a 100 ft shallow yard french drain costs roughly $1,000 to $3,500 installed ($10 to $35 per linear foot), with a mid estimate near $2,200. DIY materials for the same run cost about $1,400 to $2,100, so the pro premium is mostly one day of excavation labor, not parts.
Five jobs, one name
Before touching the calculator, make sure you are pricing the right job. These are the five systems people mean by "french drain," with 2026 installed ranges:
| Drain type | Per linear foot | Typical total | What it is |
|---|---|---|---|
| Shallow yard / surface | $10–35 | $500–5,300 | Trench under 2 ft collecting surface water |
| Curtain drain | $10–25 | $1,500–8,800 | Shallow uphill interceptor catching water before the house |
| Exterior footing drain | $30–90 | $1,200–4,500+ per side | Excavated to foundation depth; depth is the cost |
| Interior crawl space | $20–40 | $2,000–8,000 | Same concept, no concrete demolition |
| Interior basement perimeter | $40–100 | $4,000–17,000 | Concrete floor broken, tile laid, floor re-poured, sump required |
The jump from shallow to deep is almost entirely excavation: a yard trench is a day of digging, while a footing-depth trench is priced by the cubic yard of soil moved. The interior basement jump adds concrete demolition, dust control, re-pouring the floor, and a sump pump, which is why it runs roughly triple the shallow rate.
How the cost math works
Low total = length × low $/ft + sump low
Mid total = length × mid $/ft + sump mid
High total = length × high $/ft + sump high
The worked example: 100 ft of shallow yard drain at $10/$22/$35 per foot gives $1,000 / $2,200 / $3,500 with no sump. Adding a sump pump tacks on $800 to $2,500 for the basin, pump, and discharge line. The range is honest, not vague: your soil, access, and depth decide where in it you land, which the next section covers.
What moves a quote between low and high
Key takeaways: the five cost drivers
- Depth. The single biggest driver. Every extra foot of trench is cubic yards of digging, hauling, and backfill.
- Soil and rock. Hitting rock can double or triple excavation cost; heavy clay slows everything down.
- Access. A mini-excavator in an open yard is cheap; hand-digging along a fenced property line is not.
- The outlet. Free if the yard slopes to daylight; four figures if you need a sump pump, dry well, or storm connection.
- Restoration. Sod, mulch, and paver resets run 15 to 30 percent on top and are often billed separately.
The outlet problem
A drain without a discharge point is a buried bathtub.
Water collected by the pipe has to go somewhere: daylight to a slope, a dry well, or a sump pump lifting it out. No outlet, no drainage, no matter how perfect the trench. Price the water problem first, then the trench: confirm where the water exits before you sign anything, because adding a sump or dry well later can cost more than the drain itself. Also confirm the discharge does not just move the problem onto a neighbor's lot, which creates liability no drain is worth.
DIY or hire a pro?
DIY: viable for shallow drains
- A 25 ft shallow drain costs about $528 in materials and tool rentals ($21/ft)
- Trench, fabric, washed gravel, perforated pipe: no exotic skills
- You control the slope and the outlet, the two things that matter most
Hire a pro: for deep and interior work
- DIY can actually cost MORE per foot than a pro on shallow work once rentals add up
- Wrong pipe slope, wrong gravel, or skipped fabric means digging it all up again
- Call 811 before any digging: utility strikes are dangerous and expensive
The honest math surprises people: at $21 per foot DIY for a short shallow run versus $10 to $35 per foot pro, doing it yourself can cost more than hiring out, before counting your weekend. DIY wins on longer runs where the pro's labor scales and your material cost does not. Interior basement work is never DIY: breaking and re-pouring a structural slab is licensed-contractor territory.
What competing calculators miss
Search for a french drain cost calculator and you mostly find cost-guide articles with a single national average, or quote forms wearing a calculator costume. The averages blend five different jobs, so a $4,000 "average" tells a yard-drain shopper they will overpay and a basement-waterproofing shopper they got a bargain, both wrongly. None of the interactive tools separate drain types, almost none include the sump pump as a line item even though interior systems require one, and the DIY comparison is usually absent or reduced to "rent a trencher." This calculator starts from the drain type because that single choice explains most of the tenfold price spread, prices the sump separately, and shows the DIY materials number next to the pro range so the premium is visible, not hidden. If the drainage project ties into a larger septic or grading job, our septic cost calculator covers drain fields and related excavation, and for new construction the new home cost calculator keeps foundation drainage in the full budget.
Frequently asked questions
It depends on the type: $10–35 for a shallow yard drain, $10–25 for a curtain drain, $30–90 for an exterior footing drain, $20–40 for an interior crawl space, and $40–100 for an interior basement perimeter. Depth is the biggest driver of where you land in each range.
A 100 ft shallow yard drain runs $1,000 to $3,500 installed. The same length as an exterior footing drain is $3,000 to $9,000, and as an interior basement perimeter $4,000 to $10,000 plus a sump pump at $800 to $2,500.
A curtain drain is a type of french drain placed uphill to intercept groundwater before it reaches the house or yard, usually shallower and cheaper at $10–25 per foot. "French drain" is the family name; curtain, footing, and interior perimeter drains are the members.
Only when gravity cannot do the job. If the trench can slope to daylight, a street drain, or a dry well, no pump is needed. Interior basement systems almost always need one, and flat lots often do too. Budget $800 to $2,500 installed for the basin, pump, and discharge.
Shallow yard and curtain drains are reasonable DIY: trench 18 to 24 inches deep, line with geotextile fabric, bed of washed gravel, perforated pipe with holes facing down, more gravel, wrap the fabric, backfill. Budget about $14–21 per foot in materials plus tool rentals. Deep exterior and interior work belongs to pros.
Shallow yard drains: 18 to 24 inches deep and 9 to 12 inches wide. Footing drains go to the foundation footing, often 6 to 8 feet deep, which is why they cost triple. Deeper is not automatically better: the drain must sit below the water problem and slope continuously to its outlet.
A properly built drain with geotextile fabric, washed gravel, and correct slope lasts 30 to 40 years. The killer is silt clogging the pipe or fabric, which is why the fabric wrap and washed (not crushed-with-fines) gravel matter more than the pipe brand. Flush the system every year or two through an inspection port.
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References
- HomeGuide, How Much Does a French Drain Cost? (2026): per-foot costs by drain type and interior system pricing. Accessed October 2026.
- Lawn Love, How Much Does a French Drain Cost in 2026?: itemized DIY cost breakdown and pro-vs-DIY comparison. Accessed October 2026.
- LSU AgCenter, Landscape Ornamental Series: Installing and Maintaining a French Drain: trench dimensions, pipe, gravel, and geotextile specifications. Accessed October 2026.
- Engineer Fix, How to Build a French Drain: Step-by-Step Instructions: slope, pipe orientation, and fabric wrap method. Accessed October 2026.
- Land Clearing and Excavation, French Drain Cost in 2026: Per Foot, by Type: five-jobs-one-name pricing framework. Accessed October 2026.