What Laval publishes for additional units
Laval requires a permit to add an additional dwelling within an existing single-family house. The city’s current page describes several internal or attached configurations and makes clear that a fully detached additional unit follows a different rule set rather than being automatically permitted.
Open the official Laval suite source ↗The broader Montréal region housing pattern does not replace the Laval approval file. Confirm this address and unit type with the local source.
Quebec: the provincial layer
Quebec’s current housing legislation creates a provincial accessory-housing right in defined circumstances, while municipalities retain important siting, construction, architectural, parking and land-development standards and can use available exemptions.
Quebec accessory-housing provincial framework ↗Four things to establish before the renovation
What kind of unit?
Different dwelling forms can have different size, siting, servicing and permit requirements even on one property.
Is the use allowed?
Separate entitlement from construction. The city may allow another unit in principle while still regulating its size, location or form.
Can the building comply?
Do not budget only for finishes. Code work can include exits, alarms, fire separations, mechanical changes and structural alterations.
Can the site serve it?
Site constraints can include parking, sewer and water capacity, electrical service, waste access and setbacks for a detached unit.
The practical Laval suite sequence
Treat permission for another dwelling and approval of the construction as separate questions. Zoning answers one; building and trade permits answer the other.
When a property is marketed with a suite, verify the actual municipal approval file before relying on the rental income in your planning.
Official sources
Reviewed 2026-09-14. This municipality has a topic-specific suite or ADU source. Pair it with the provincial layer and verify the current property and permit requirements.