Montreal
Do you need a permit for a deck or balcony in Montreal?
A permit is required to build, enlarge, alter or replace a deck, balcony, gallery or front steps, with rare exceptions; no permit for maintenance.
Permit requiredA zone, a heritage area or a shoreline can have its own standards: with your address, the Radar reads your zone's grid and tells you what applies to your property.
The rules, in short
Rules of the Ahuntsic-Cartierville, Rosemont–La Petite-Patrie and Ville-Marie boroughs. Each Montreal borough has its own by-law: check your address.
- Rosemont–La Petite-Patrie: no permit for a deck detached from the building whose floor is less than 60 cm above the ground; a permit above 60 cm. (montreal.ca "Building or replacing a deck…", Rosemont–La Petite-Patrie section)
- Ville-Marie: a permit for a deck whose floor is more than 60 cm above the ground, and for any rooftop deck; north of Sherbrooke Street, a certificate is required for any landscaping. (montreal.ca "Building or replacing a deck…", Ville-Marie section)
- Ahuntsic-Cartierville: a permit to build, enlarge, alter, move or replace a deck, balcony, gallery or front steps. (montreal.ca "Building or replacing a deck…", Ahuntsic-Cartierville section)
Summary by Radar Foncier, in our own words: the official French text of the by-law, linked above, prevails.
Applying in Montreal
- Processing time: Varies by borough (no general processing time published)
- Cost: Varies by borough; example shown on montreal.ca: $9.80 per $1,000 of work, with a minimum ($167.40 for a pool)
- Urban planning department: 311
- Permits on the municipality's website
Other projects in Montreal
Deck, patio or balcony elsewhere: Côte Saint-Luc, Dorval, Gatineau, Sherbrooke, Vaudreuil-Dorion, Westmount.
Version française de cette page
Source: Borough urban planning by-laws: Ahuntsic-Cartierville (01-274), Rosemont–La Petite-Patrie (01-279) and Ville-Marie (01-282); rules taken from the montreal.ca how-to pages for these 3 boroughs only, checked on October 22, 2026. Plain-English summary: the official French text prevails, and a by-law can change. Confirm with the Montreal urban planning department before buying materials. Radar Foncier is an independent service, not affiliated with the municipality.
Radar Foncier in English. Permits and rules for Québec homeowners; the full site and the reports are in French. Version française