Accessory Apartment
A guide to prepare your building permit application.
When creating an accessory apartment, you need a bedroom, a kitchen, living area, washroom and access to laundry facilities. Combined spaces are permitted.
Project preparation
Verify that your plans, proposed dimensions and location are permitted under the Town of Oakville's zoning by-laws which regulate the use, shape and location of buildings on properties.
To learn more visit our Zoning page or contact us at 905-845-6601 ext. 3955.
You will require a separate zoning certificate of occupancy approval. Apply online at online services.
Heritage properties are managed to conserve important cultural heritage attributes. If your property is on the town's heritage registry it may require heritage approval. Learn more on our Heritage Planning page or contact a town Heritage Planner for assistance at 905-845-6601 ext. 3870 or 3875. If you are making changes to the building façade for windows or doors you will need heritage approval.
Accessory apartments require minimum window sizes based on the room they are located in and associated area.
If you plan to add an egress door with a walk up stairs, you will need to consult an engineer or BCIN qualified designer for construction drawings and details
If your project includes excavation and your property backs onto green space, a river bed or wetland you will need Conservation Halton approval. Learn more at Conservation Halton. Contact Conservation Halton for approval at web@hrca.on.ca or 905-336-1158.
- Trees on your property, your neighbor's property and on the municipal right of way may require tree protection, particularly when heavy equipment and excavation is involved. In certain instances, a separate permit may be required to remove private trees. Visit our Licensed Contractors page to find an arborist.
- A separate site alteration permit may be required when digging, excavating or altering the grade. Contact ServiceOakville for more information.
- Digital copies of drawings and documents are required, scaled to size and flattened. If preparing the documentation is beyond your comfort level or experience, we recommend working with a Building Code (BCIN) qualified designer, architect or engineer.
- Contact Ontario One Call at 1-800-400-2255 before you dig to locate underground utilities and avoid damage during construction.
To add an accessory apartment to your property you will need a building permit.
Visit our Building Permits page for details.
Submission material checklist
Prepare the following documents and apply online on our Online Services page.
Select the hyperlinks for example drawings and documents:
- Site plan
- Elevations
- Floor plans, fire separations and details
- HVAC design (location of supply outlets and return inlets) and Part 6 design (if applicable to your project)
- Engineered walk-up stair details (if applicable to your project)
- Water service calculation
- Schedule 1 designer qualification (required when someone other that an architect or engineer is designing the project)
- Zoning certificate of occupancy approval
- Heritage approval (if applicable to your property)
- Conservation approval (if applicable to your property)
- Fee (payable at time of application)