Protect your drinking water — before it's too late.
A defective or missing backflow preventer exposes your home to serious health risks: sewage backing up into your drinking water network or basement. We install certified, tested, and Quebec-compliant devices.
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The Silent Trap of Sewer Backup
In Quebec, over 40% of basement water damage incidents are caused by sewer backup — not leaks.
The Real Cost of "I'll Do It Later"
An average backup costs between $15,000 and $50,000 in cleanup, decontamination, floor replacement, and belongings losses.
Insurance, Resale, and Compliance: Three Legal Reasons to Act
Since 2023, several insurers require proof of certified backflow preventer installation to cover basement water damage.
A Customer's Story: The Backflow Preventer That Saved Their Basement — And Health
« After a storm, our neighbors had 3 feet of black water in their basement. Us, nothing. Why? Because Plomberie Despaties had installed a real certified backflow preventer six months earlier. »
— Jean-Marc T., Sainte-Dorothée
Our Installation Process — Compliance, Safety, Durability
We don't just install a backflow preventer. We ensure your system withstands the next storm.
Risk Assessment
Analysis of topography, flood history, and inspection of existing drain.
Permit and Documentation
Submission of RBQ permit, coordination with the city, and delivery of a complete file.
Certified Installation
Installation by RBQ technicians with pressure tests, precise alignment, and leak-proof connections.
Operational Verification
Testing under real conditions to confirm the backflow mechanism works.
What's included in each intervention
CSA-Certified Device : Double check valve with automatic relief, compliant with Quebec's Plumbing Code.
RBQ Permit Included : We handle all administrative procedures and official inspections.
Performance Testing : Validation by hydraulic pressure and observation of the mechanism in action.
Certificate of Compliance : Official document for your insurance and future buyers.
Why choose Plomberie Despaties?
We're not a franchise or a call center. We're a local team, certified RBQ and CMMTQ, dedicated to residential plumbing in the greater Montreal area.
Specialized Expertise
Few plumbers master the subtleties of backflow prevention systems.
Total Transparency
No additional charges for permits, inspections, or certified materials.
RBQ #5866-6652-01
Active license, civil liability insurance, and strict compliance with provincial standards.
Local Knowledge
We know the high-risk areas in Montreal and Laval.
Areas served
Fast and reliable service in over 40 neighborhoods and cities around Montreal.
Island of Montreal
Laval
North Shore
Frequently asked questions
Clear and honest answers from a licensed expert — no sales.
A Faulty Backflow Preventer Is Worse Than No Backflow Preventer
A defective device creates a false sense of security. Meanwhile, your children drink potentially contaminated water.
RBQ #5866-6652-01 | Serving Montreal, Laval, North Shore, South Shore