Building permits in Oakville, heritage and creeks first.
The Town of Oakville reviews building permits here. We prepare the permit drawings for additional residential units, additions, renovations and new homes, as a BCIN-qualified designer, and take the application through to an issued permit.
- Covers
- Oakville, Bronte, Glen Abbey, North Oakville
- Region
- Halton Region
- Conservation
- Conservation Halton
- Zoning
- By-law 2014-014; 2009-189 north of Dundas
- ARUs
- Up to 2, one of them detached
- Min. permit fee
- $200
- From Ancaster
- About 35 minutes
What comes before the building permit?
- 01Is the house on the Town’s Heritage Register?
- 02What does the lot back onto?
- 03What are you planning?
Old Oakville & downtown. All four heritage conservation districts sit here, between Sixteen Mile Creek and Second Street. The Sixteen Mile Creek valley on the west side and the lake along the south. Zoning: Zoning By-law 2014-014.
- Heritage permit
- Check Most streets here are inside a district. Search the address on the Town's Heritage Register map first.
- Conservation Halton
- Likely Inside the regulated area, adding a dwelling unit counts as development even with no new floor area.
- Heritage permitStaff and the Heritage Oakville Advisory Committee, monthly. On the 2026 calendar, about 6 to 10 weeks from a submission deadline to a decision.
- Conservation Halton permissionPre-consult first. Completeness within 21 days, then a four-week review target, with a 90-day legal limit.
- Zoning Certificate of Occupancy$300, for turning space into a second suite. Applied for in the same Online Services account.
- Building permitOnline through ePlan, with drawings in ProjectDox. $100 pre-screen fee, credited to the permit.
Heritage and Conservation Halton can run side by side. The Town's checklist asks for both approvals with the permit application, so start them before drawings are final.
Most changes to the house need a permit.
Inside the house
Finishing a basement, a basement apartment (second unit), interior alterations, and adding, removing or moving a sink, tub, toilet or shower.
Openings and structure
A new door or window, or making one bigger. Dormers, skylights, underpinning, and roof changes that raise the height or change the slope.
Below grade
A below grade entrance or basement walkout, digging down for more headroom, and shoring and excavation.
New floor area
An addition, an attached or detached garage, a covered porch, and any building over 10 m² or with plumbing.
Outside
A deck over 0.61 m (two feet) high that is attached to the house, and re-cladding in a different material, such as siding to brick.
No permit needed, per the Town’s own list:
- A shed, cabana or gazebo under 15 m² with no plumbing
- Replacing a door or window in the same size opening
- Replacing a plumbing fixture in the same spot
- Cabinets, painting and decorating
- Re-shingling, and re-cladding in the same material
- A fence, landscaping, or a retaining wall under 1 m
- Widening or resurfacing a driveway
The work still has to meet the zoning by-law, permit or not. Digging, excavating or changing the grade can also need a separate Town site alteration permit (the Town calls it a DENG permit). Electrical work goes to the Electrical Safety Authority. Not sure where your project falls? Start with do I need a permit?
Two additional units, one of them detached.
Oakville calls a second suite an additional residential unit. An attached unit sits inside the house, such as a basement apartment. A detached unit sits in an accessory building, such as a garden suite or a converted garage. South of Dundas Street the rules are in Zoning By-law 2014-014; between Dundas Street and Highway 407 they are in the North Oakville By-law 2009-189. Check which one covers your lot on the Town’s zoning map.
| Rule | What the Town allows |
|---|---|
| Units per lot | The main home plus 2 additional units: 2 inside the house, or 1 inside and 1 detached (2014-014 s. 4.1.2; 2009-189 s. 4.29.3) |
| Which houses | Detached, semi-detached, linked and townhouse dwellings (2009-189 lists detached, semi and townhouse) |
| Entrances | An entrance to an additional unit cannot face a yard narrower than 1.0 m |
| Detached height | 4.0 m measured from grade (2014-014 Table 6.5.3) |
| Detached setbacks | 1.2 m from the interior side and rear lot lines and 3.5 m from a flankage lot line, when 2.0 m or more from the house; closer than 2.0 m, it follows the main building's yards |
| Detached size | Lot coverage up to the greater of 5% of the lot or 42 m², counted inside the overall lot coverage in a Residential Low zone |
| Parking (2014-014) | 2 spaces for a detached, semi or townhouse dwelling, plus 1.0 additional parking space for an attached or detached additional unit (Table 5.2.1); tandem spaces allowed for any dwelling (s. 5.1.10) |
| Parking (2009-189) | No additional parking spaces required for an additional unit |
| North Oakville detached units | 2009-189 sets no separate size or setback rules for a detached unit (s. 4.29); the accessory building rules apply (s. 4.14): 4.0 m tall, no closer to the street than the house, 1.2 m from the interior side lot line (0.6 m for a first storey with no doors or windows facing it), 0.6 m from the rear lot line, 2.0 m from the house |
| Servicing | The Town asks for a water service pipe sizing form with an additional unit, to show the existing service can carry the extra load |
The detached-unit table above came in with By-law 2026-088, passed June 15, 2026. Read with the 2014-014 parking table, it is not clear whether the 1.0 extra space applies per unit or once, so confirm the number for your lot with Zoning.
What the Town charges.
| Item | 2026 Town fee |
|---|---|
| Minimum permit fee | $200, with a $100 pre-screen fee paid at submission and credited to the permit |
| Accessory dwelling unit | $12.00 per m² |
| Interior alterations, basements and finishing | $4.90 per m² |
| New houses and additions | $17.80 per m² |
| Garages and unheated accessory buildings | $5.90 per m² |
| Walk-up basement, deck | $400 and $220 each, where no other work is proposed |
| Demolition, revisions to a permit | $438 each |
| Zoning Certificate of Occupancy | $300, for a basement turned into a second suite |
| Accessory Dwelling Unit Registration | $800 each, a new fee in the 2026 schedule; the schedule does not say when it applies, so ask Building Services |
| Conservation Halton (if regulated) | $285 simple, $550 minor, $1,790 intermediate, $5,865 major, for a single residential lot |
Last verified 2026-10-11
Development charges. The Town lists the creation of additional dwelling units, in existing and new residential buildings, as a mandatory exemption under the Development Charges Act, within the Act’s limits. Education development charges may still apply to units that are exempt from Town and Halton Region charges, and they are collected before the permit is issued. Development Finance confirms the numbers for your address.
- Check statusTown of Oakville ARU incentive
We found no Town grant or loan for additional units. The Town says it is exploring programs through an Affordable Housing Community Improvement Plan.
- ClosedHeritage Grant Program 2026
Up to half of eligible conservation work on a designated property, to a maximum of $15,000. The 2026 intake is closed and under review; additions are not eligible.
Paying for it? See cost and financing and how our pricing works.
How an application goes in.
Check zoning and overlays
Zoning map, Heritage Register and the Conservation Halton regulation map. The Applicable Law Form lists what else is needed.
Other approvals
Heritage permit, Conservation Halton permission, a Zoning Certificate of Occupancy for a second unit, tree or DENG permits where they apply.
Submit online
Through Online Services, with drawings uploaded to ePlan (ProjectDox) as vector PDFs named to the Town's standard.
Pre-screen and review
A $100 pre-screen, then an invoice. Comments come back in ProjectDox; resubmit only what was asked for.
Permit issued
Then inspections at the stages the Building Code requires.
Accessory apartment checklist. Site plan, elevations, floor plans with fire separations and details, the drawings and calculations the Town asks for, walk-up stair details where there is one, the water service sizing form, Schedule 1 designer information, the tree protection declaration, the zoning certificate, and heritage and conservation approvals where they apply.
Additions checklist. A site plan with zoning statistics, the full drawing set, truss packages, the energy efficiency design summary, and a grading plan when the addition is over 50 m².
Review times. The Town follows the Large Municipalities Chief Building Officers process timelines and says review times change with volume, complexity and resubmissions. It does not publish a day count, so we do not either. We do not publish a time for our own work.
The Town recommends a BCIN-qualified designer when the drawings are beyond your experience. We prepare the drawings and forms, submit them and answer the examiner’s comments. Structural work, where needed, is coordinated with an outside licensed professional.
Full breakdown: renovation process.
Near a creek, the lake or a heritage street?
Oakville has four heritage conservation districts. Every property inside one is designated under Part V of the Ontario Heritage Act, and changes to it need a heritage permit. Listed (not designated) properties do not. Heritage permits go to staff and the Heritage Oakville Advisory Committee monthly; on the 2026 calendar, a decision lands about 6 to 10 weeks after the submission deadline.
| District | Since | Roughly covers |
|---|---|---|
| Old Oakville | 1981 | South of Robinson Street to the lake, from Sixteen Mile Creek east to Allan Street. |
| First and Second Street | 1987 | Lakeshore Road East to the lake, between Allan Street and Second Street. |
| Trafalgar Road | 1994 | Sixteen Mile Creek east to Reynolds and Allan Streets, Spruce Street south to Sumner Avenue. |
| Downtown Oakville | 2013 | Roughly Navy Street to Dunn Street, from just north of Randall Street to Lakeshore Road East. |
Individually designated (Part IV) houses sit across the Town too, from Bronte Road to Burnhamthorpe Road. Search the address on the Town’s Heritage Register map.
What we design in Oakville.
Basement apartments and garden suites
Permit drawings for a legal additional residential unit.
Additions
Rear, side and second-storey additions.
Alteration drawings
Permit drawings for renovations to an existing home.
Load-bearing wall removal
Framing plans for every floor, as the Town asks, with the structural work coordinated.
New builds
Detached and semi-detached homes.
Do I need a permit?
A self-check before you call anyone.
Oakville questions.
How many additional units can I have in Oakville?
Two additional residential units on top of the main home: either two inside the house, or one inside and one in a detached accessory building. That applies to a detached, semi-detached, linked or townhouse dwelling, under both Zoning By-law 2014-014 (s. 4.1.2) and the North Oakville By-law 2009-189 (s. 4.29.3).
Does my property qualify?Do I need anything besides the building permit for a basement apartment?
Yes. The Town asks for a separate Zoning Certificate of Occupancy for turning a basement into a second suite. It costs $300 and is applied for through the same Online Services account. The Town's 2026 fee schedule also lists a new $800 Accessory Dwelling Unit Registration fee; confirm with the Town when it applies to your unit.
Do I pay development charges on a second unit in Oakville?
The Town lists the creation of additional dwelling units as a mandatory exemption under the Development Charges Act, within the limits the Act sets. The Town also says education development charges may still apply to units that are exempt from Town and Region charges. Development Finance confirms the numbers for your address.
My house is in Old Oakville. Do I need a heritage permit?
A heritage permit is needed to change a property designated under the Ontario Heritage Act, which includes every property inside the Town's four heritage conservation districts. Listed (not designated) properties do not need one. The Town says window and door changes on the façade of a heritage property need heritage approval. Applications go to the Heritage Oakville Advisory Committee on a monthly calendar.
My lot backs onto a creek. What changes?
Conservation Halton regulates land near watercourses, valleys, wetlands and the Lake Ontario shoreline under Ontario Regulation 41/24. Inside that area, adding a dwelling unit counts as development even with no new floor area, so its permission comes before the building permit. It confirms completeness within 21 days and aims to review within four weeks of a complete application.
How big can a garden suite be in south Oakville?
Under Zoning By-law 2014-014 (Table 6.5.3, as amended by 2026-088), a detached additional unit can be up to 4.0 m high from grade, at least 1.2 m from the interior side and rear lot lines and 3.5 m from a flankage lot line when it sits 2.0 m or more from the house. Its coverage is the greater of 5% of the lot or 42 m², counted inside the lot's overall coverage in a Residential Low zone.
Garden suite requirementsDo I need a permit to replace my windows?
Not if the new window goes into the existing opening at the same size. A new window, or a bigger one, needs a permit. On a designated heritage property, a façade change to windows or doors also needs heritage approval.
Nearby.
We’ll tell you what the Town allows on your lot.
Zoning, heritage, Conservation Halton and the permit path for your address, before you spend a dollar on drawings.