What is a Calgary backyard suite?

A Calgary backyard suite is a self-contained secondary dwelling unit built on the same residential lot as the primary home — separate from the main house, typically located at the rear of the property. You may also hear them called garden suites, garage suites, laneway suites, or carriage houses depending on the configuration.

Backyard suites have become increasingly popular in Calgary since the city expanded permissions for them across most residential neighbourhoods. They serve as mortgage helpers, multi-generational living spaces, or long-term rental income properties — and with Calgary's 2024 blanket rezoning to the R-CG district, most residential lots in the city can now accommodate one.

What the Rules Look Like

The City of Calgary sets clear parameters for backyard suites. The maximum size is 85 square metres (approximately 915 square feet), and the suite can be up to two storeys. It must sit on the same property title as the primary home — you cannot subdivide and sell it separately. Setback requirements apply to the rear and side property lines, and your overall lot coverage (all buildings combined) cannot exceed the maximum for your zone. The suite must have its own separate entrance, and if it's above a garage, the garage portion counts toward the overall structure.

You'll need both a development permit and a building permit from the City of Calgary before breaking ground. Development permit processing typically runs 6 to 12 weeks, so factor that into your timeline. Apply through the City's online portal at calgaryplanningpermit.ca. Surrounding communities like Airdrie, Cochrane, and Okotoks have their own rules — contact those municipal offices directly if your property is outside Calgary.

What It Costs to Build

In the Greater Calgary market, expect to budget in the range of $150,000 to $350,000 for a backyard suite, depending on size, finishes, and whether it's above a garage or a standalone structure. A basic above-garage suite lands closer to the lower end; a fully finished two-storey garden suite with high-end finishes pushes toward the top. Costs include foundation work, framing, mechanical (plumbing, electrical, HVAC), insulation, drywall, kitchen, bathroom, and exterior finishing.

Calgary's expansive clay soils can add cost if the foundation requires additional engineering — this is worth a soil assessment before you design. All footings must extend below the frost line of 1.2 metres (4+ feet), which is one of the deepest requirements in Canada.

Permits and Code Requirements

Beyond the development and building permits, you'll also need separate electrical, plumbing, and gas permits — all inspected by Safety Codes Officers through the City of Calgary. The suite must meet Alberta Building Code requirements for fire separation, egress windows in bedrooms, minimum ceiling heights, and interconnected smoke alarms with the primary dwelling. These are non-negotiable, and the City of Calgary actively enforces compliance.

Is It Worth It?

For most Calgary homeowners, a well-built backyard suite pencils out over time. Rental income in Calgary for a 600–900 sq ft suite typically ranges from $1,400 to $2,200/month depending on location and finishes. That said, you're looking at a significant upfront investment with a multi-year payback period, so run the numbers carefully before committing.

Your next step is to confirm your lot's eligibility and zoning through the City of Calgary's online mapping tools, then consult with a designer or architect familiar with Calgary's backyard suite requirements. Browse experienced contractors in our directory at Calgary Construction Network to find builders who specialize in secondary suites and infill construction.