Guide

    Backyard suite vs secondary suite

    Two ways to add a second home to a Calgary property — and since the rezoning repeal, a choice between them rather than both.

    The distinction

    A secondary suite is a self-contained dwelling inside the existing house — most commonly a basement suite. A backyard suite is a self-contained dwelling in a separate building in the rear yard, often above a garage, in which case people call it a carriage house or laneway home.

    Why the choice matters now

    • Since August 4, 2026, a property may have one of a secondary suite or a backyard suite — not both.
    • Backyard suites are not allowed on semi-detached properties.
    • The parking requirement returned.
    • Backyard suites are permitted in R-G. In other zones they are discretionary and require City verification.

    The first point is the one that changes planning: if a property already has a secondary suite, a backyard suite is off the table, and vice versa.

    What each option demands of the property

    Secondary suite

    • Depends on the existing house: ceiling heights, egress windows, fire separation, mechanical separation.
    • No new building footprint, so rear-yard dimensions are not the constraint.
    • Shares the building envelope with the main dwelling.

    Backyard suite

    • Depends on the lot: width, rear yard depth, lane access and parking.
    • Must satisfy the City's dimensional baselines:
    • Minimum lot width: 9 m — 9 metres is the common minimum lot width. A width of 7.5 m can apply on certain corner or lane properties with three or more motor-vehicle stalls. Confirm your parcel with the City.
    • Rear setback: 1.5 m — Minimum distance from the rear property line.
    • Side setback: 1.2 m — Minimum distance from the side property line, subject to exceptions.
    • Separation from main dwelling: 5.0 m — Minimum separation between the backyard suite and the main house.
    • Maximum height: 7.5 m — Maximum building height for the backyard suite.
    • Outdoor amenity area: 7.5 m² minimum — Minimum outdoor amenity area, with no side of that area less than 1.5 m.
    • Maximum suite area: Commonly 75 m² — The commonly applied maximum floor area for the suite itself.

    Backyard suites are permitted in R-G and discretionary in other zones, and are not allowed on semi-detached properties.

    How to decide

    Screen the lot first with the feasibility tool. If the lot clears the baselines, a backyard suite is worth pricing with the cost-driver worksheet. If it does not, a secondary suite may be the realistic path — confirm requirements with the City through the permit process.

    Screening only — not an approval. This is a screening tool, not an approval. Nothing on this page confirms that a backyard suite can be built on a specific property — only the City of Calgary can do that through the development and building permit process.

    Facts on this page are drawn from current City of Calgary pages and were last reviewed August 31, 2026. Rules change and every parcel is different. Verify current requirements with the City of Calgary before making any decision.