This is an explainer rather than breaking news: the rule has been in force since 2024 and 2025, and the city's page was last updated September 12, 2025. We include it because it is the clearest Canadian example of a municipality ruling out new furnace installs in new buildings, and furnace companies across the country get asked about it. The Ville de Montréal's page on the ban sets out the rules summarised below.
What the by-law bans
The direct answer: combustion appliances that emit greenhouse gases are banned in most new buildings in Montréal.
Under the Règlement sur les émissions de gaz à effet de serre des nouveaux bâtiments, banned equipment in new construction includes indoor air or water combustion heaters (which covers gas, oil and propane furnaces and boilers), indoor gas fireplaces, residential gas or propane stoves, barbecues connected to a gas network, and pool or spa heaters connected to a gas network. The city names oil, natural gas, propane and biodiesel among the fuels.
Still allowed: emergency generators, wood fireplaces permitted under municipal by-law, commercial gas cooking equipment, outdoor barbecues and patio heaters on removable tanks, and temporary heaters used during construction.
Which buildings, and from when
The by-law covers new residential, commercial and institutional buildings, in two groups:
| Building type | Definition | In force |
|---|---|---|
| Small buildings | Up to 3 storeys and 600 m² per floor | October 1, 2024 |
| All other buildings | More than 3 storeys or more than 600 m² per floor | April 1, 2025 |
Projects with a complete, compliant building permit application filed before those dates are excluded. Applicants must disclose energy sources when applying for a new construction permit.
Exceptions and exclusions
- Renewable gas: large buildings may use combustion appliances if emissions come only from renewable gas, with proof of supply kept on file.
- Connection delay: small buildings may qualify if Hydro-Québec's connection delay is more than 12 months after the permit is issued.
- District energy: buildings connected to a district thermal network are excluded.
- Industry: manufacturing plants, such as food processing, are excluded.
The page states plainly that existing buildings are not covered. It links a separate city roadmap toward zero-emission buildings by 2040, which we have not reviewed for this explainer.
Contractor analysis: what it means for furnace companies
This section is FurnaceNews.ca analysis, not part of the city's page.
New construction in Montréal is no longer furnace territory. For residential builders and the mechanical contractors who work for them, new Montréal projects are now heat pump, electric or district-energy jobs, with narrow exceptions.
Existing homes are a different market. The ban does not touch existing buildings, so replacing, servicing or converting a gas furnace in an existing Montréal house remains legal under this by-law. Province-wide, Quebec's separate ban on installing or replacing oil heating since December 31, 2023 still applies, as covered in our oil conversion brief. For gas-heated existing homes, the province's dual-energy program offers a path that keeps the furnace as backup; see our dual-energy brief.
Get the message right on your website. Homeowners hear "Montréal banned gas" and assume it applies to them. A short, dated FAQ explaining that the ban covers new buildings only, with a link to the city, prevents lost service calls.
Watch other municipalities. Montréal shows how a city can act through building permits. Contractors elsewhere should follow their own council's building and climate by-laws, because rules like this change the long-term mix of furnace work.
Marketing in Montréal also has to respect Quebec's language law; our Quebec page explains. For campaigns built around what is still allowed, see our dual-fuel campaign service, and for other briefs, the newsroom.
A quick reference for call-takers
When a homeowner asks about the Montréal ban, three sentences cover most calls:
- The ban applies to new buildings, from October 1, 2024 for small ones and April 1, 2025 for the rest.
- Existing homes are not covered by this by-law, so service and replacement in an existing gas-heated house continue.
- Separate provincial rules already stop new oil heating installs in Quebec.
Keep a link to the city's page handy, and confirm current details there before quoting dates to a customer.
FurnaceNews.ca is a news and marketing service for heating contractors. We are not a municipality, a regulator or a heating contractor, and this is not legal advice. Confirm current rules with the Ville de Montréal.
Frequently asked questions
Can a gas furnace be installed in a new Montréal home?
Generally no. Montréal's by-law bans greenhouse-gas-emitting combustion appliances for space and water heating in new residential, commercial and institutional buildings, with limited exceptions.
Does the ban apply to existing homes?
No. The city's page states that existing buildings are not covered by this regulation.
When did it take effect?
October 1, 2024 for small buildings (up to three storeys and 600 m² per floor) and April 1, 2025 for all other buildings. Projects with a complete, compliant permit application filed before those dates are excluded.
Are there exceptions?
Yes. Large buildings may use combustion appliances if emissions come only from renewable gas. Small buildings may qualify if Hydro-Québec's connection delay is more than 12 months after the permit. Buildings on a district thermal network and manufacturing plants are excluded.