What are the height restrictions for additions in Ottawa?

Building height restrictions for additions in Ottawa depend on your specific zoning designation, but most residential areas have a maximum height limit of 11 meters (36 feet) for the main building.

The City of Ottawa's Zoning By-law 2008-250 sets different height limits based on your property's zoning:

Residential Zones (Most Common):

• R1, R2, R3 zones: Maximum 11 meters to highest point of roof


• R4, R5 zones: Often 11-13 meters depending on specific zone


• Some newer subdivisions may have different restrictions

What Counts Toward Height:
Height is measured from average grade to the highest point of the roof, including chimneys, antennas, or other projections. Basement levels that are mostly below grade typically don't count toward the height calculation.

Before Planning Your Addition:
Contact the City of Ottawa Building Code Services at 613-580-2424 to verify your specific property's zoning and height restrictions. You can also check your zoning online through ottawa.ca/building or GeoOttawa mapping tool using your address.

Additional Considerations for Additions:
Beyond height, your addition must meet setback requirements from property lines, lot coverage maximums (typically 30-40% of lot area), and angular plane restrictions that prevent overshadowing neighboring properties. Two-story additions often trigger more complex zoning reviews.

The Permit Process:
Height-compliant additions still require building permits through the City of Ottawa. Expect 15-25 business days for permit approval and fees ranging from $500-2000+ depending on the addition's size and complexity. Your contractor should verify all zoning compliance before starting design work.

Red Flags to Avoid:
Never proceed with an addition without confirming height compliance first. Some contractors may promise to "make it work" without checking zoning - this can result in costly modifications or even demolition orders. Always verify your property's specific zoning designation and restrictions before finalizing plans.

Getting Professional Help:
For complex additions near height limits, consider hiring an architect or designer familiar with Ottawa's zoning requirements. They can maximize your addition while ensuring full compliance with all height, setback, and coverage requirements.

For specific project design questions about your addition, check out renovation specialists who can help optimize your space within Ottawa's zoning requirements.