Practical Guide
How to Cut Your Heating Bill in Quebec: Where to Start
Two houses of the same age, on the same street in Laval, can show a gap of several hundred dollars per winter. It …
Two violent storms in one summer are enough to turn a finished basement into a claim. In Montreal as in Laval, the municipal by-law already requires certain devices, and Laval’s says in black and white that the City is not answerable for the damage if you do not have them. Here is the work involved, what the City subsidizes, and what you will have to declare on the day you sell.
The Greater Montreal climate in 2050, and the bill already paid
On August 29, 2024, at the citizens’ forum of the Office de consultation publique de Montréal, Ouranos presented a numbers based portrait of the island for 2050, under a moderate emissions scenario.
| Index, Montreal region | 1991 to 2020 | 2041 to 2070 |
|---|---|---|
| Annual precipitation | 861 mm | 969 mm |
| Winter rain | 93 mm | 135 mm |
| Snow | 222 cm | 198 cm |
| Freeze and thaw in winter | 27 days | 35 days |
| Days above 30 °C | 10 days | 26 days |
Ouranos adds one figure that speaks directly to a basement: an annual maximum precipitation event that historically had a 5% chance of occurring each year could have a 10% to 14% chance around 2046 to 2065.
Insurers do not project, they pay. According to the Bureau d’assurance du Canada, the cost of insured catastrophic losses in Quebec has averaged more than 877 million dollars a year over the past five years. Canada wide, 2024 set a record at 9.1 billion dollars, against a five year average of 4.3 billion.
Backwater valve: the obligation exists, and so does the disclaimer
This is where many owners get it wrong. A backwater valve is not an optional improvement, and its absence carries a legal price.
In Laval. By-law L-11870, adopted on October 6, 2014, covers water and sewer connections, drainage and the management of runoff on private property. Its section 5.05.02 requires the owner to install a specific list of safety devices: backwater valves, check valves, backflow preventers, a backup pump, cleanout access, a crown in a sunken driveway, rainwater drainage from a sloped roof, and a watertight retention sump. For a building already erected, the by-law allowed 18 months to comply. That deadline passed long ago.
Section 5.05.01 sets out the standard: valves go upstream of the main collector, on every discharge connection located below the crown of the street. Only normally closed valves are permitted, installing one on the main collector is prohibited, and a floor drain fitted with a built-in device does not exempt you from the obligation. Maintenance required: at least once a year. The lift pump must deliver a minimum flow of 2.6 l/s at a total head of 3 m.
Then comes section 5.05.03, titled « Exonération de responsabilité », the disclaimer of liability: the City is not responsible for damage caused to a building or its contents if the owner fails to install or maintain those devices. The technical sheet from Laval’s Service de l’environnement repeats the same rule at section 3.03.02 of the former by-law L-5057.
In Montreal. The framework is the Règlement sur la protection des bâtiments contre les refoulements d’égout (11-010). The City writes that since 2011, valves must be installed in all new buildings, and that installation becomes mandatory under the municipal by-law for anyone who has already suffered a flood or a backup. The retention sump must measure at least 600 by 450 by 450 mm and be equipped with a pump, connected where possible to a battery system, because an outage often comes with the storm. Maintenance recommended: twice a year.
On the insurance side, the Bureau d’assurance du Canada is blunt: most standard policies do not cover damage caused by sewer and drain backup. Coverage comes through an optional endorsement. The BAC also recommends a sump pump with a backup battery and properly graded land. What a heavy claims history does is detailed in a hard to insure home in Quebec, and the spring mechanism in spring melt and basement water infiltration.
What Montreal subsidizes in resilience work, and as of what date
The RénoPlex program targets buildings of 1 to 5 dwellings. For blocks 1 and 3, the building’s assessed value must be less than or equal to $3,860/m². Block 3 covers flood protection work only, with a minimum grant request of $500. Block 1 requires a minimum of $3,000. The ceilings: $26,000 for a single-family house, $52,000 for a building of 2 to 5 dwellings.
| Work | Amount granted |
|---|---|
| Normally closed backwater valve | $90 |
| Valve under an existing slab | $600 per valve |
| Retention sump and pump | $1,600 per building |
| Foundation drain, interior or exterior | $60 per linear metre |
| Window well installed or repaired | $400 per window well |
| Roof drain diverted | $3,750 per building |
| Green roof | $100 per square metre |
| Asphalt replaced with vegetation or permeable pavers | $1,700 per building |
Two warnings matter as much as the amounts. First, you have to wait for written confirmation before starting the work, or the right to the grant can be lost, and the City announces a delay of 3 to 4 months. Second, these figures move. On September 25, 2026, the amounts page, updated on August 18, 2026, showed $90, $600 and $1,600, while the City’s article on the backwater valve, updated on July 15, 2025, still showed $80, $560, $1,500 and a threshold of $3,476/m². Two pages, two sets of figures. Have the amount and the threshold confirmed at the time you apply.
Low slope roof: the white membrane is no longer an aesthetic choice
In Montreal, replacing the covering of a flat or low slope roof, meaning less than 2:12 or 16.7%, requires a permit. And the list of permitted materials is closed: a material that is white, painted white or covered with a reflective coating or white gravel, a material whose solar reflectance index reaches the required threshold, or a green roof.
The threshold itself depends on the borough. The City page, updated on February 2, 2026, asks for an index of at least 66 in Ahuntsic-Cartierville and at least 78 in Anjou. The manufacturer’s technical sheet showing that index is one of the documents required in the file. The by-laws involved are the Règlement d’urbanisme 01-274 and the Règlement sur la construction et la transformation de bâtiments 11-018. The analysis fee follows the cost of the work: $9.80 per $1,000 bracket, minimum $167.40 for residential.
RénoPlex adds a technical requirement of its own: a flat roof redone under the program has to be redone with a white membrane. Before committing that budget, the home value estimator gives a starting range for your building.
Rainwater on your lot: the one metre rule
In Laval, section 5.05.01 is precise about the water coming off the roof. Rainwater from a sloped roof must be carried away by a system of gutters and exterior downspouts, and must discharge onto a permeable surface at least 1 metre from the building. Connecting a downspout to the foundation drain is prohibited, and so is sending that water toward a driveway. It is the cheapest job on this whole list and the one most often neglected.
On the drain itself, I would rather be clear: no official source lets me put a figure on the service life of a Quebec foundation drain. What can be verified is its condition, by camera, as explained in a sagging sewer drain in Montreal.
Summer overheating: air conditioning moves from comfort to file
Ten days a year above 30 °C, then 26: that is the Ouranos projection for Montreal. The discomfort of a top floor under a black roof becomes a showing topic in July.
RénoPlex grants $1,350 per targeted dwelling to replace an oil or natural gas heating appliance with a central heat pump, and $1,000 per dwelling for central electric heating. Those amounts fall under block 1, not the flood component.
Hydro-Québec pays by capacity. The LogisVert program pays $50 per 1,000 BTU/h at -8 °C for an ENERGY STAR certified heat pump, $120 for a cold climate model and $140 for a very high efficiency heat pump, weatherstripping work included. The announced maximum is $6,700, increased by 5% if the application combines several measures. In an eligible multi-dwelling building located in an area covered by the program’s deprivation criteria, a top-up of $100 per 1,000 BTU/h brings the amount to $220, for installations made as of June 15, 2026. Amounts posted by Hydro-Québec in September 2026.
Climate resilient renovations: what gets declared at resale
The mandatory Déclarations du vendeur sur l’immeuble form, DV 00001 version 06/2022, asks the question for each of these jobs. D8.1 and D8.2: the type of roof covering and its year of installation. D9.2: a sump or a retention pit. D9.3: a sump pump, its year and its operating frequency. D9.4: a foundation drain, and whether a system allows access to inspect and clean it. D9.12: problems related to wastewater discharge. D9.13: a backwater valve. D12.12 and D12.13: the heat pump and the permanent air conditioning system, with the year and the documents. Add D2.12, on non-compliance notices received from an insurer or the municipality, and D2.13, on a refusal of insurance.
This work is not guessed at: it is declared, with the invoices and the years. On the price gain, though, no official source lets me put a number on what a valve or a white membrane adds to a sale value. What can be verified is the reverse effect: a « no » at D9.13 becomes an inspection question, a condition or a deduction.
| Property type | The first thing to look at |
|---|---|
| Finished, lived-in basement | Valve, retention sump, backup pump |
| Flat roof plex | Membrane, reflectance index, permit |
| Sloped garage driveway | Crown in the driveway and a connected sump |
| Flat lot, short downspouts | Discharge onto a permeable surface at 1 m |
| No cooling at all | Heat pump and shading |
Frequently asked questions
Will my insurer require a backwater valve? The Bureau d’assurance du Canada recommends installing a valve according to your municipality’s recommendations, and points out that most standard policies do not cover sewer backup without an endorsement. The precise conditions belong to your insurer: ask them in writing.
I have a built-in valve in my floor drain. Is that enough in Laval? No. By-law L-11870 says that a floor drain fitted with a built-in device does not exempt you from the obligation to install a separate valve on the discharge connection.
Can I redo my flat roof in black if the material is new? In Montreal, no, unless the material reaches the solar reflectance index required by your borough. The manufacturer’s technical sheet has to attest to it, and replacing the covering requires a permit.
Is the RénoPlex grant still open? On September 25, 2026, the program page showed the status « en cours », under way. A municipal program can be modified or suspended, and the amounts differ from one City page to another. Check with the Service de la stratégie immobilière et de l’habitation before signing a contract.
Who has to do the plumbing work? The Ville de Montréal refers you to a contractor who is a member of the Corporation des maîtres mécaniciens en tuyauterie du Québec, and asks for a certificate of compliance handed over with the invoice. Keep that certificate: it will serve twice, first for the insurer, then for the buyer.
To go further, read the seller’s declaration in Quebec and what home maintenance costs in Quebec.
Wondering which of these jobs your property actually requires? Write to me. We look at your city’s by-law together, and at what your declarations will tell the buyer.
Georges Matar
Residential Real Estate Broker · RE/MAX DU CARTIER INC.
Contact Georges
