Renovation permits in Montreal: when do you actually need one?

In Montreal, residential renovation permits are not issued by the central City. They are issued by the boroughs. That is the first thing that catches homeowners off guard. Two identical houses, one in Rosemont and one in Verdun, can go through two different processes for the same work, because each borough applies its own planning by-laws on top of the municipal framework.

Here is how to find your way through it, what actually triggers an application, and why permits belong at the start of a project rather than the week before demolition.

Work that almost always requires a permit

The logic behind the by-laws is straightforward: as soon as the work affects the safety of the building, how many people it houses, or how it looks from the street, the city wants to see it before it is built.

• —Touching the structure: removing or altering a load-bearing wall, changing joists, redoing a foundation, lowering a basement floor.
• —Adding space: rear extensions, added storeys, sunrooms, any increase in habitable volume.
• —Altering the envelope: new openings, changing the cladding, roofing work that modifies the structure.
• —Changing the number of dwelling units: adding or removing a unit, converting a plex.
• —Altering the exterior appearance in sectors where the borough regulates architecture: windows, doors, front stairs and balconies.
• —A good share of plumbing and electrical work, particularly when services are moved or added.

Work that normally does not

Anything that stays cosmetic, with the layout unchanged, usually does not trigger an application.

• —Paint, wallpaper, mouldings.
• —Replacing floor coverings.
• —Replacing kitchen cabinets without moving plumbing or electrical.
• —Replacing a plumbing fixture in the same location.

How an application unfolds

1. 1Confirm with the borough whether a permit applies, before anything gets drawn.
2. 2Have the required drawings produced. Depending on the work, that means a building technologist, an architect or a structural engineer.
3. 3File the application with the documents your borough requires.
4. 4Answer requests for clarification. This is where most of the delay happens: an incomplete file goes back to the bottom of the pile.
5. 5Receive the permit, post it on site, then start the work.

Timelines vary by borough, by time of year and by how complex the file is. In sectors subject to architectural review, expect an additional committee step. That is why we build permits into the schedule during planning, rather than treating them as a last-minute formality.

What an unpermitted job risks

• —A stop-work order, with the site open and subcontractors already mobilized.
• —Fines, plus the obligation to regularize after the fact.
• —Having to undo work that looks compliant but was never authorized.
• —An insurance problem: a loss connected to undeclared work can complicate a claim.
• —A blocked sale, when the inspection or the notary uncovers unpermitted work.

One more point many homeowners are unaware of: in Quebec, renovation work above $2,000 must be carried out by a contractor holding a licence from the Régie du bâtiment du Québec. A contractor who offers to "skip the permit" is offering to hand you the risk.

Letting your general contractor handle the permit

This is the main point of a genuine turnkey contract. At Kasa, the permit application is part of the service: we retain the professionals required, assemble the file, submit it on the client’s behalf and follow it through to issuance. The homeowner never has to go back and forth with the borough, and the construction schedule reflects the real timeline rather than a hoped-for one.

That applies just as much to a full home renovation as to an extension or a post-disaster rebuild, where the permit also has to be coordinated with the insurer.