Garden Suite & ADU Builder in Oakville & Burlington
What Is a Garden Suite or Additional Residential Unit?
A garden suite (also called a coach house, backyard suite, or detached additional dwelling unit) is a small, self‑contained home in a separate building on the same lot as your main house. It has its own kitchen, bathroom, living area, and sleeping space, and is typically located in the rear yard as an accessory building.
Under Ontario’s updated planning framework and Oakville’s and Burlington’s zoning by‑laws, these units are treated as Additional Residential Units (ARUs) or Detached Additional Dwelling Units, and are now permitted on many low‑rise residential lots, subject to local rules on size, height, setbacks, and services.
Why Homeowners Are Adding Garden Suites
Oakville, like Burlington, has embraced “gentle density,” allowing multiple units on a single lot when they meet zoning and Building Code requirements. In many residential zones, you can now combine attached and detached additional units — for example, a basement suite plus a detached backyard suite — up to a maximum of three additional dwelling units on one property, depending on dwelling type.
That opens up powerful options:
- Multi‑generational living – Create a private, fully independent home for parents, adult children, or extended family, on the same property.
- Rental income – Add a high‑quality, legal rental unit to offset your mortgage or increase long‑term cash flow.
- Future flexibility – Use the space today as an office, studio, or guest suite, and convert to a rental or family unit later.
- Property value – Well‑designed, code‑compliant additional units can significantly increase resale appeal in a supply‑constrained market.
Golden Brick Homes helps you do this legally, with full attention to zoning, life‑safety, and long‑term value.
What You Need to Know (At a Glance)
Zoning details reviewed October 2026 (Zoning By-law 2014-014, as amended by By-laws 2023-024, 2024-111 and 2026-088). Rules vary by zone and lot — we confirm yours before design.
Every property is different, but here are the rules that govern most garden suites and detached additional residential units in Oakville today.
- Number of units — three on the lot, not four. Oakville permits your main home plus a maximum of two additional residential units: either two attached units, or one attached unit and one detached garden suite. Only one additional unit may be detached.
- Location — a detached additional residential unit in Oakville sits in the rear yard as an accessory building to the main home. Setbacks — 4 ft and 11 ft 6 in. Once the suite sits at least 2.0 m from the house, it needs 1.2 m (4 ft) from the interior side and rear lot lines and 3.5 m (11 ft 6 in) from a flankage lot line. Closer than 2.0 m to the house and it takes the main building’s setbacks instead, which are far larger.
- Height — 13 ft 1 in (4.0 m), and no corner-lot catch. The maximum height is 13 ft 1 in (4.0 m), measured from grade. No corner-lot reduction applies to a garden suite — the 2.5 m rule people quote governs non-habitable accessory buildings under Table 6.5.2, not an additional residential unit.
- Size — it is a footprint limit, not a floor area limit. The rule is the greater of 42 m² (about 450 sq ft) or 5% of your lot area, and it governs lot coverage — the ground the building occupies. A well-designed suite with a loft can carry more interior floor area than the number suggests — there is no floor-area cap at all in the by-law, only height and coverage.
- The “-0” zone exception, and it is a big one. In the “-0” Suffix Zone areas of south Oakville, no additional lot coverage is permitted for accessory buildings. A garden suite has to fit inside the coverage your house is already using. If your property is in a “-0” zone, check this before anything else.
- Setbacks — 0.6 m, conditionally. The 0.6 metre minimum applies to a building in the rear or flankage yard, and only where it sits at least 2.0 metres from the house. In an interior side yard the full side yard of your zone applies instead. Entrances also cannot face a yard narrower than 1.0 metre.
- Parking — the by-law requires 1.0 additional parking space for an additional residential unit, on top of what the main dwelling already requires.
- Servicing — south of Highway 407, no building may be erected unless the land is on municipal water and sewage.
- Permits — a building permit is always required, and the unit must meet the Ontario Building Code with proper water, sanitary and hydro connections. We confirm the exact zone standards for your parcel with Town of Oakville Planning Services before design begins, and that is included in every Golden Brick garden suite project.
We offer a turnkey, builder‑led approach:
01.
Feasibility & Zoning Review
Review zoning, heritage, and conservation constraints
Identify the best location and realistic size/height options for your suite
02.
Concept Design & Budgeting
Provide preliminary budget ranges and ROI considerations
Refine plans to balance function, aesthetics, and cost
03.
Detailed Design & Permits
Prepare and submit building permit and any necessary minor variance applications
Address Town comments and conditions until permits are approved
04.
Construction & Project Management
Install mechanical, electrical, and plumbing systems to current code
Finish interiors with durable, attractive materials suitable for daily living or rental
05.
Handover, Inspection & Support
Walk you through all systems and maintenance basics
Provide documentation for rental, refinancing, or resale
Typical Uses for Garden Suites & ARUs
- Private in‑law suite or aging‑in‑place residence
- Independent space for adult children or boomerang kids
- Short‑ or long‑term rental for additional cash flow
- Dedicated home office, studio, or practice with its own entrance
- Future‑proofed flexibility if your family’s needs change
Garden Suite FAQs
How long does a garden suite permit take in Oakville?
Plan for roughly 2 to 4 months from first design meeting to permit in hand: about 4-8 weeks for design, drawings and zoning review, then typically 2-6 weeks for the Town of Oakville to review a complete, code-compliant building permit application. A compliant application moves fastest — revisions and zoning relief add time.
How much does a garden suite cost in Oakville?
Garden suite cost in Oakville typically lands between $250,000 and $450,000+ turnkey, depending on size, finishes, site servicing (water, sanitary and hydro runs) and foundation conditions. Smaller studio-scale suites can come in lower; larger or high-specification suites cost more. Servicing runs and site access move the number most, and both are lot-specific.
What are the size and height limits for a garden suite in Oakville?
A detached additional residential unit in Oakville can be up to 4.0 metres tall, measured from grade, with a footprint up to the greater of 42 square metres or 5% of your lot area. Two details catch people out. That 42 m² figure is a lot coverage limit, not a floor area limit, so a lofted design can deliver more interior space than it sounds. And in the “-0” Suffix Zone areas of south Oakville, accessory buildings get no additional lot coverage at all, so the suite has to fit within your home’s existing coverage. Height also drops to 2.5 metres within 3.5 metres of a flankage lot line on a corner lot. Setbacks are 0.6 metres from rear and flankage lot lines where the suite sits at least 2.0 metres from the house; an interior side yard requires the full zone setback. Most lots may have three dwelling units in total: your main home plus two additional units, only one of which may be detached. Standards vary by zone, so we confirm your exact parcel with Town of Oakville Planning Services before design.
What changed for garden suites under Oakville’s 2026 zoning by-law?
Council adopted By-law 2026-088 on 15 June 2026, amending Zoning By-law 2014-014 for the low-density residential areas south of Dundas. The appeal deadline was 13 July 2026. According to the Town’s notice it consolidates the Residential Low “RL” zones into “R” zones, converts the “-0” Suffix Zone into an Overlay, and introduces height requirements based on roof slope, driveway setbacks, soft landscaping requirements and new minimum yards for additional residential units. Here is the position as of October 2026: By-law 2026-088 was approved by the Ontario Land Tribunal on 20 August 2026 under subsection 34(19) of the Planning Act, in Case OLT-26-000698, and is now in force. The Town’s consolidated Part 6 now carries the new R zones. The figures on this page reflect the by-law as enacted. If you are planning a suite now, we confirm the live standards for your specific lot with the Town before you commit to a design.
Can I rent out a garden suite in Oakville?
Yes. A legal, permitted garden suite can be rented as a long-term rental home, making it a genuine income-generating asset. Short-term rentals (under 28 days) are restricted under Oakville’s licensing rules, which generally limit short-term accommodation to a host’s principal residence. Many owners use suites for family first, rental income later.
Where Do You Want to Start?
A garden suite starts with one question: what does your lot actually allow? Every path below begins with a free, no-obligation answer.
- Check what my backyard allows. — A free feasibility chat: zoning, setbacks, servicing and whether your lot supports a detached suite.
- See what my property is worth with a suite. — A builder-informed valuation, including how an added unit affects value and rental income.
- I’m building new and want a suite from day one. — Designing the main home and the suite together is cheaper than adding one later.
Questions first? Call (647) 772-1642 or start here.
Want to go deeper on the rules and numbers? Read our guides: Garden Suites in Oakville — 2026 Rules, Costs & Permits and Building a Garden Suite in Oakville, Burlington & Mississauga.
Ready to Explore a Garden Suite or Additional Residential Unit?
Whether you’re planning multi-generational living, house-hacking, or simply future-proofing your property, Golden Brick Homes can help you design, permit, and build a legal, high-quality additional unit in Oakville and Burlington.
Garden suites by city
Every municipality sets its own standards. The rules on this page are Oakville and Burlington. For Mississauga, the numbers are different, and we have a separate page for them.
- Garden suites in MississaugaTwo storeys permitted on lots over 8,073 sq ft. Different setbacks and heights.
- Oakville garden suite rules 2026Costs, permits and what By-law 2026-088 changed.
