Garden suites & ADUs · Oakville
Garden Suites in Oakville
Oakville calls a garden suite a detached additional residential unit: a self-contained home in an accessory building on the same lot as a detached house, semi, linked house or townhouse.
The rules, in plain language
What Oakville allows
Under Oakville's Zoning By-law 2014-014 (Section 4.1 and Table 6.5.3), a lot can have either two attached additional residential units, or one attached unit plus one detached unit. Oakville's rules for detached units are some of the tightest in the region, so a single-storey design is usually the starting point.
Size and height
- Maximum height 4.0 m, measured from grade.
- Maximum lot coverage for the unit: the greater of 5% of the lot or 42.0 m².
- In Residential Low zones, that coverage counts toward the lot's overall maximum. In other zones it is in addition to the dwelling's coverage.
- Source: By-law 2014-014, Table 6.5.3, as of November 1, 2026
Location and setbacks
- In the rear or flankage yard, at least 2.0 m from the main house: 1.2 m from the interior side and rear lot lines, and 3.5 m from the flankage lot line.
- Closer than 2.0 m, or in the front or interior side yard, it must meet the main house's setbacks.
- Entrances can't face a yard narrower than 1.0 m.
- Source: By-law 2014-014, Part 4 and Table 6.5.3, as of November 1, 2026
How many units
- Up to two attached units, or one attached and one detached unit.
- Source: By-law 2014-014, Section 4.1.2, as of November 1, 2026
Check with the city: parts of Oakville (North Oakville) use a different zoning by-law, 2009-189. Oakville also passed By-law 2024-053 allowing up to three additional units on some lots, but the consolidated Section 4.1.2 we read shows one attached plus one detached. Confirm the current permissions for your lot. These pages don't state parking, servicing, development charges or permit fees, so ask Oakville Planning and Building.
How we build it
Five ways to build in Oakville
01
Geohaus factory-built
Perimeter Homes is a Geohaus partner. Studio, one- and two-bedroom layouts built in a factory and set on your lot.
See the Geohaus layouts02
Modular / prefab
Factory-built modular garden suites and backyard homes, with sizes adjustable to your lot and local rules.
Browse the model gallery03
Custom stick-built
Framed on site for tight, sloped or oddly shaped lots, or a layout no catalogue covers.
How custom worksEvery design still has to fit Oakville's zoning for your lot. We check that before you commit.
Common questions
Oakville garden suite FAQ
How tall can a garden suite be in Oakville?
4.0 m from grade (Zoning By-law 2014-014, Table 6.5.3).
How big can it be?
Oakville limits lot coverage for a detached unit to the greater of 5% of the lot or 42.0 m².
How close to the lot line?
1.2 m from the interior side and rear lot lines when it is at least 2.0 m from the house in the rear or flankage yard.
Does North Oakville follow the same rules?
North Oakville is under By-law 2009-189. Check your lot's zoning.
Sources
Official city sources
- Oakville Zoning By-law 2014-014, Part 4: General Provisions (as of November 1, 2026)
- Oakville Zoning By-law 2014-014, Part 6: Residential Zones (as of November 1, 2026)
This guide summarizes public city information and isn't planning or legal advice. Rules change. Confirm your lot with the city before you apply.
Start here
Talk to a garden suite builder.
Tell us about your lot and which option you're considering. We reply within one business day.