Garden Suites & Laneway Houses · ARUs
Garden suite permit drawings — feasibility first.
BCIN #511123. Garden suites, laneway suites and coach houses. We confirm the lot actually qualifies — setbacks, fire access and servicing — before you spend on design.
- Feasibility check first — does your lot actually qualify?
- Emergency access route measured early; it's the usual blocker.
- Servicing — water and sanitary connections confirmed before design.
- We file the application with your municipality for you.
Get a fixed quote
Tell us the municipality and what you're planning — same-day reply on weekdays.
What It Is
What is a garden suite?
A garden suite is a self-contained detached dwelling in the rear yard of an existing house — its own kitchen, bathroom and entrance, on the same lot as the main home. Depending on the municipality and where it sits, the same thing may be called a laneway suite, a coach house, or simply a detached additional residential unit (ARU).
Because it is a complete new dwelling rather than an alteration, it carries the full weight of the Building Code plus a specific set of by-law rules about size, placement and access. The single most common reason a garden suite doesn't proceed is not design — it's that the lot fails one of the access or servicing tests. That's why the feasibility check comes first.
Code & By-Laws
What the Code and by-laws generally require
Garden suite rules are municipal and they vary a great deal — Toronto's laneway and garden suite by-laws are not Mississauga's. Broadly, a lot is tested against:
- Whether the lot qualifies at all under the municipality's garden or laneway suite by-law.
- Lot size, setbacks and maximum footprint, plus overall lot coverage including the main house.
- Height limits and, in many municipalities, angular plane or overlook restrictions toward neighbours.
- Separation distance between the suite and the main dwelling.
- Emergency access route — the distance a firefighter must travel from the street, plus gate and path widths.
- Servicing — whether water and sanitary run separately or share the existing connections, and whether an upgrade is needed.
- Spatial separation — limiting distance and unprotected openings on walls near lot lines.
- Energy compliance — a full SB-12 package, as for any new detached dwelling.
- Parking and tree protection — an arborist report is commonly required.
- Full Part 9 design — foundation, framing, insulation, HVAC and plumbing.
This is a general guide, not a code review. What applies to your project depends on the scope, the municipality and the age of the building — tell us what you're planning and we'll confirm what's actually needed.
Related Work
Detached dwellings & second units.
Garden suite projects currently in progress aren't shown yet. These are the closest completed sets — a detached single-storey dwelling designed end to end, and self-contained second units with their own entrances, kitchens and fire separations.