French drain cost calculator
Get a realistic price range for your French drain in under 30 seconds. Set the sliders to match your house and watch the range update as you go — no commitment, no email address required.
A typical 25 × 40 ft house has a perimeter of roughly 130 linear feet.
A full basement usually sits 7 to 8 ft down, a crawl space 4 to 5 ft.
Estimate based on 2026 Quebec market benchmarks. Indicative amounts only; the written quote determines the actual price.
How we build the estimate
Our ranges come from indicative 2026 benchmarks for Greater Montreal, then get adjusted for the six factors that matter most on site.
Length of the perimeter
The larger the house, the more there is to dig. The cost per linear foot eases off a little on longer runs, but the total still goes up.
Depth of the foundation
A full basement costs more to expose than a crawl space, because the excavation has to go all the way down to the footing.
Soil type
Clay digs easily, rock does not. Running into rock can add $3,000 to $10,000 to the project.
Access and obstacles
A deck, a pool, mature trees, fencing or a tight lot next to the neighbours all slow the work down and add labour hours.
Materials chosen
A higher-grade dimpled membrane (Delta-MS), new clean stone or adding a sump pit push the price up — and the service life with it.
Condition of the foundation
If cracks or damage show up once the wall is exposed, repairing them is added to the work quoted at the start.
Want the pricing explained in detail? Our full guide “Coût d'un drain français au Québec en 2026” goes through it line by line (in French).
Your questions, our answers
As a general guide, the ranges most often seen are $10,000 to $25,000 for a new installation and $3,000 to $8,000 for a targeted repair. The final price depends on the site and on the scope confirmed in the quote.
Need an exact price for your project?
The calculator gives you an order of magnitude. For a detailed price, our team can assess the site and confirm the scope of work in a written quote.