Can I convert my detached garage into a laneway suite in Sunnyside, or are there flood restrictions?

Converting a detached garage to a laneway suite in Sunnyside is technically possible under Calgary's zoning rules, but flood restrictions will likely prevent it. Sunnyside is located in the Bow River floodway and is subject to strict flood mitigation requirements that typically prohibit habitable spaces below the flood construction level.

Flood Restrictions in Sunnyside

Sunnyside sits directly in the Bow River floodway and was severely impacted by the 2013 Calgary flood. The City of Calgary has implemented strict flood mitigation policies for this area. Any new residential construction or conversion must be built above the designated flood construction level (FCL), which varies by specific location but is typically several feet above existing grade in Sunnyside.

Most existing detached garages in Sunnyside were built at grade level, well below the required flood construction level. This means you would likely need to either:

• Raise the entire structure above the FCL (extremely expensive and often not feasible)


• Build a new structure on an elevated foundation


• Potentially flood-proof the structure to meet City requirements

The Bow River flood fringe designation covers much of Sunnyside, and the City requires detailed flood impact assessments for any new residential development in these areas.

Laneway Suite Requirements

If flood restrictions weren't an issue, your garage conversion would need to meet Calgary's backyard suite (laneway suite) requirements:

• Maximum 85 square meters (915 square feet)


• Maximum 2 storeys


• Must remain on the same property title as the main house


• Requires both a development permit and building permit


• Must meet Alberta Building Code requirements for residential occupancy


• Separate electrical service or proper electrical separation from the main house


• Proper insulation, heating, plumbing, and fire separation

Next Steps

Contact the City of Calgary's flood resilience team first at 311 or through calgary.ca to determine the exact flood construction level for your property. You'll need a site-specific flood assessment before any planning can proceed. The City's Planning Department can also confirm current zoning restrictions for your specific lot.

If flood restrictions make conversion impossible, consider alternative uses for your garage that don't require residential occupancy - such as a workshop, studio, or storage space that can be designed to handle periodic flooding.

Find structural engineers and architects experienced with Calgary flood regulations in our directory - you'll need professional expertise to navigate both the flood requirements and the laneway suite development process.