Carriage houses: what BC and Alberta cities allow in 2026

You've got a detached garage at the back of the lot and a teenager who's about to be an adult, a parent who needs to be closer, or a mortgage that would feel lighter with rent coming in. In the Okanagan and the Lower Mainland, the answer people reach for is a carriage house. Here's what cities actually allow, from their own bylaws and guides.

What is a carriage house?

It's a separate dwelling with its own kitchen, bathroom and living space, secondary to the house on the same lot. Penticton's definition covers a purpose-built building or a renovated garage, and says it can't be sold separately from the house (Penticton.pdf)). The same thing goes by other names: Surrey calls a unit above or attached to a garage a coach house, Calgary calls it a backyard suite "also known as" a carriage house, Edmonton calls it backyard housing, and Ontario towns use coach house or laneway house. Our ADU guide maps the names across provinces.

Can I build a carriage house in BC?

Very likely, in some form. Under BC's small-scale multi-unit housing rules (Bill 44), every municipality had to allow a secondary suite and/or a detached accessory dwelling unit in single-family zones by June 30, 2024, and larger towns must allow three or four units on most single-family lots (Province of BC). A city can choose to allow only a suite on some lots, and the Province advises against detached units on lots under a hectare without a sewer connection (policy manual). Bill 25 (2025) extended the rules again, with bylaw updates due by June 30, 2026.

How big can a carriage house be?

It depends on the city, and the gap is wide:

Sources: Penticton.pdf), West Kelowna, Surrey, Saanich, Calgary bylaw s. 352, Edmonton bylaw s. 6.10.

Our take: if you have a lane, design for two storeys over a garage. In Penticton the lane is what unlocks 7.0 m instead of 5.0 m, and a second storey keeps the yard you'd otherwise lose to a sprawling one-storey unit.

Do I need a permit for a carriage house?

Yes: always a building permit, and often a development permit too. Calgary requires both for every backyard suite, plus trade permits (Calgary). Penticton dropped its form-and-character development permit in June 2025 but still requires a building permit, an occupancy inspection before anyone moves in, and a business licence before you rent it (Penticton.pdf)). West Kelowna says permits take 4 to 10 weeks and fines an illegal carriage house $500 a day (West Kelowna).

What does a carriage house cost?

A site-built backyard suite costs $180,000 to $400,000 by our 2026 estimate, and a prefab or modular one $150,000 to $300,000 before delivery, crane and site work. City fees add more: West Kelowna's own worked example comes to about $17,000 in fees and development cost charges for a 90 m² carriage house, including about $70 per m² in City charges and regional sewer charges (West Kelowna). In BC, a licensed builder also registers the home with BC Housing (BC Housing). Our cost estimator adds servicing and site work.

Can a carriage house be sold separately?

Usually not. Penticton's definition says it can't be sold apart from the house, and Edmonton's bylaw says backyard housing can't be subdivided or made part of a bare land condominium (Edmonton). Kamloops is an exception: carriage and garden suites there may be strata-titled (Kamloops).

Can I finance a carriage house?

One route is CMHC-insured refinancing to add a suite: up to 90% of the home's value including the value the suite adds, up to four units, for an owner-occupied home worth under $2 million, as long as the suite is legal and rented for at least 90 days at a time (CMHC). BC's Secondary Suite Incentive Program stopped taking applications on March 31, 2025, and Calgary's Backyard Suite Incentive Program closed on September 28, 2026.