Westmount
Do you need a permit for a deck or balcony in Westmount?
A building permit is required for an accessory structure, decks included (By-law 1634, s. 38).
Permit requiredThe rules, in short
- A deck or balcony attached to the house is part of the building: the building line, open-space and lot-coverage rules apply, as does the PIIA (site planning and architectural integration programme). (art. 6.17.1)
- Free-standing deck: at most 0.30 m above the highest ground level (1.52 m above the lowest); its distance from a property line must be at least twice its height. (art. 6.17.2)
- Privacy screen on the deck at most 2 m high; pergola at most 3 m above the ground. (art. 6.17.2)
- Galleries, balconies and front steps may project up to 2.13 m past the building line, 0.60 m from the sidewalk. (art. 5.2.3.2)
Summary by Radar Foncier, in our own words: the official French text of the by-law, linked above, prevails.
Applying in Westmount
- Urban planning department: 514 989-5219
- Permits on the municipality's website
Other projects in Westmount
Deck, patio or balcony elsewhere: Côte Saint-Luc, Dorval, Gatineau, Montreal, Sherbrooke, Vaudreuil-Dorion.
Version française de cette page
Source: Zoning By-law 1303 (administrative consolidation up to By-law 1641; accessory dwelling units: By-law 1657), French version, checked on October 25, 2026. Plain-English summary: the official French text prevails, and a by-law can change. Confirm with the Westmount 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