Service 01
French drains:
installation and replacement
When the drain around your foundation is clogged, crushed or simply absent, water sits against the concrete. We excavate, rebuild the entire system to BNQ standard, and put your yard back the way it was.
How to tell your drain is done
A French drain has a service life. Old clay-tile drains and unprotected flexible pipe clog with soil fines, get crushed under the weight of backfill, or fill with roots. Most owners only find out when water comes in.
- Water appearing at the base of basement walls during the thaw or after heavy rain.
- A persistent damp or musty smell, even with a dehumidifier running.
- White efflorescence (salt deposits) on the concrete.
- Paint or drywall blistering at the bottom of finished walls.
- A sump pump running more and more often — or never at all.
- Ground that stays soaked along the foundation for days after rain.
We always start with an inspection. In many cases, high-pressure jetting or a camera run through the drain is enough to establish whether it can be saved. If it can, we say so — that’s a few hundred dollars instead of several thousand.
Our method, step by step
- Inspection and diagnosis. Level survey, basement inspection, check of the sump pit and yard grading. Photos included.
- Site protection. Pavers, slabs and salvageable sod lifted and set aside. Access routes protected and underground services located (Info-Excavation).
- Excavation down to the footing. We expose the foundation wall over its full height, down to the bottom of the footing. It’s the only way to work on the right plane.
- Wall cleaning and repair. Concrete cleaned, cracks repaired and the wall prepared before waterproofing.
- Waterproofing. Polyurea membrane or bituminous coating depending on wall condition, followed by the drainage board.
- Drain installation. BNQ-certified rigid drain on a bed of clean stone, sloped to the sump pit, covered with 3/4 clean stone certified pyrite-free and wrapped in filtering geotextile.
- Backfill and restoration. Backfill compacted in successive layers, pavers and sod reinstalled, site fully cleaned.
Why “pyrite-free” stone matters
Pyrite is a mineral that swells when exposed to water and oxygen. Used as backfill under a slab or around a drain, it can lift concrete and crack the very foundation you just repaired. We use only 3/4 clean stone with a certificate of conformity, and we keep the delivery slips.
What the quote includes
- Underground service locates and any required municipal permits.
- Excavation, hauling and disposal of excavated material.
- Repair of cracks discovered during excavation.
- Waterproofing membrane and drainage board.
- BNQ rigid drain, certified clean stone and geotextile.
- Compacted backfill, yard restoration and cleanup.
- Job-site photos and a written warranty at completion.
French drain FAQ
How long does the job take?
Can a French drain be installed from the inside?
Will my trees and hedges survive?
Does this also solve my humidity problem?
On site
Drainage and foundation work
Next step
We come look,
and we tell you straight
If your drain can be saved, we’ll say so. If it can’t, you get an itemized quote where every line is explained.