French Drain Installation Cost Calculator
Estimate the cost of French drain installation based on length, type, and your location.
A french drain installation costs $2,500 to $10,000, with a national average of $5,000. Use the calculator below to estimate your cost by size, quality tier, and location.
Last updated: March 25, 2026
French Drain Installation Cost Calculator
Estimate the cost of French drain installation based on length, type, and your location.
Estimated Total
$5,900
Itemized Breakdown
This calculator provides estimates based on national averages adjusted for your region. Actual costs may vary significantly based on specific project conditions, contractor availability, material prices, and local market factors. Always get at least 3 quotes from licensed, insured contractors before starting your project.
Want the full picture?
Read our complete French Drain Installation cost guide with material comparisons, contractor tips, savings strategies, and regional pricing data.
Quick Cost Reference
Cost by Tier
Exterior French drain, shallow trench (18 inches), corrugated perforated pipe, landscape fabric, gravel backfill, about 50 linear feet
Interior perimeter French drain, 100 linear feet along basement walls, rigid PVC pipe, connected to sump pit, concrete cutting and patching
Full interior and exterior French drain system, 150+ linear feet, commercial-grade drainage board, multiple drain connections, sump pump integration, full waterproofing membrane
How This Calculator Works
This french drain installation cost calculator estimates your total project cost from four inputs: project size, quality tier, the options you select, and your location. It combines material and labor rates for your chosen tier, adds typical permit costs, then applies a regional cost multiplier so the estimate reflects pricing in your state.
Estimates use 2026 cost data cross-referenced from multiple industry sources. Treat the result as a planning range, not a quote. Your final price depends on your specific scope, material choices, and local contractor availability, so collect at least three itemized bids before you set a budget.
What Affects Your French Drain Installation Cost
Interior vs Exterior Installation
$1,000 - $5,000Interior French drains typically cost $40-$75 per linear foot because they require cutting through a concrete basement floor, excavating underneath, and patching the concrete afterward. Exterior French drains run $25-$50 per linear foot and involve trenching along the foundation, which requires heavy equipment and landscaping restoration. Interior drains are more common for existing homes because exterior excavation is more disruptive.
Length of Drain Run
$1,000 - $6,000A short 30-foot drain along one wall might cost $1,200-$2,500. A full perimeter drain (100-150 linear feet for an average basement) runs $4,000-$10,000. Exterior drains around the full foundation perimeter of a 1,500 sq ft home can push $6,000-$12,000 when you factor in equipment, excavation depth, and landscape repair.
Depth of Excavation
$500 - $2,000Exterior French drains need to be deep enough to intercept groundwater before it reaches the foundation. Typical depth is 18-24 inches for yard drainage but 4-6 feet for foundation drainage. Every additional foot of depth increases labor and equipment costs significantly. Rocky soil or high water tables add further complications.
Sump Pump Connection
$600 - $2,500Interior French drains need somewhere to send the collected water. If you already have a sump pump and pit, connection costs $200-$400. If you need a new sump pit and pump, add $600-$1,500 to the project. Most interior French drain installations include sump pump setup since the drain is useless without a way to remove the collected water.
Soil Conditions and Access
$500 - $3,000Clay soil is harder to excavate and drains poorly, which may require wider trenches and more gravel. Rocky soil requires specialized equipment. Tight access around the home's exterior can prevent heavy equipment from reaching work areas, forcing more hand digging. Interior drains in basements with finished floors require demolition and restoration of flooring.
Frequently Asked Questions
How much does a french drain installation cost?
A french drain installation costs $2,500 to $10,000 for a typical project, with a national average of $5,000. Budget projects start around $1,500, and premium work can reach $15,000. Use the calculator above for an estimate matched to your size, quality tier, and state.
How does this french drain installation cost calculator work?
It combines 2026 material and labor rates for your selected quality tier, adds typical permit costs and any options you choose, then applies a cost multiplier for your state. Adjust the inputs to see your estimate update instantly.
Is this calculator free to use?
Yes. This french drain installation cost calculator is free, requires no signup, and returns instant estimates.
Does the estimate include labor and permits?
Yes. Each estimate combines material and labor costs for your chosen quality tier plus typical permit fees. Your final price still depends on your specific scope and local contractor rates, so collect itemized quotes before budgeting.
How can I lower my french drain installation cost?
Get quotes for both interior and exterior solutions. Interior drains are often less expensive because they don't require heavy excavation equipment or landscape restoration. If you only have water issues on one wall, a partial drain (30-50 linear feet) costs far less than a full perimeter system and may solve your problem entirely.
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