A residential accessory building is a structure that serves a function that is separate or secondary to the use of your house and is located on the same lot as – but is not attached to – the house. Common examples of accessory buildings include gazebos, pergolas, garden sheds, cabanas, and garages.
Many municipal bylaws prohibit the use of accessory buildings for commercial purposes or for human habitation. This is because some building code and bylaw requirements may be less stringent for buildings that are not lived in or frequently occupied by people.
It is possible to construct a detached building for someone to live in; however, this would be considered an accessory dwelling unit (ADU), not an accessory building, and so different building code and zoning bylaw requirements would apply. Likewise, it may be possible to operate a home-based business out of a detached structure on your property, but the code and bylaw requirements for a building housing your home-based business will differ from those for a building meeting the municipality’s definition of an accessory building. This article focuses on accessory buildings and does not address these other types of detached structures.
Permit requirements for accessory buildings vary across the country. It is best to check the requirements of your local jurisdiction before you plan your project. It is important to follow all local regulatory requirements to ensure fire, construction, and structural safety standards are met. Where a building permit is required, it is the owner’s responsibility to ensure a permit is obtained prior-to construction.
In Ontario, typically only small storage sheds are exempt from building permit requirements. A shed does not require a building permit in Ontario provided that the shed
An exception to the above in Ontario occurs within unorganized townships. In these areas there is no building department to issue permits or enforce the Ontario Building Code, so all buildings constructed in unorganized townships are constructed without permits. Note that the Ontario Building Code is still applicable in unorganized townships; the code simply is not enforced in those areas.
In Alberta, accessory buildings up to 10 m² [107 ft²] that do not create a hazard are exempt from building code requirements. What does or does not “create a hazard” is up for interpretation by the local building department. However, in rural Alberta, larger structures may also be eligible under the farm building exemption. The farm building exemption applies to structures of low human occupancy associated with the operation of the farm the building is located on (e.g. a building to house livestock, store produce, or to store and maintain equipment, etc.)
In New Brunswick, an accessory building with a total floor area up to 55 m² [592 ft²] that is not intended for overnight accommodation is exempt from a building permit.
It is important to note that a building must still comply with local bylaw requirements even if the building does not require a building permit. For example, you probably would not need a building permit to construct a 6’x8’ garden shed; however, you would still need to respect the maximum height and minimum setback distances from property lines specified in your local zoning bylaw.
One of the first steps to planning your project should be a review of zoning bylaw requirements specific for your property. Zoning bylaws typically specify minimum setback distances between an accessory building and the side and rear lot lines. Zoning bylaws typically also set limits on the height and gross area of an accessory building. It is sometimes possible to get relief from a bylaw restriction through a minor variance application, though this process can be costly and time consuming.
You should also check if there are other agencies you will need to obtain approval from prior to applying for a building permit. For example, in Ontario, many areas located near a river or lakeshore are regulated by a Conservation Authority, areas along the Niagara Escarpment are regulated by the Niagara Escarpment Commission, and areas near major highways are regulated by the Ministry of Transportation.
Obtaining a Surveyor’s Real Property Report may also be necessary. You may not be able to build within certain parts of your property if they are subject to an easement or right-of-way.
If you’re planning to purchase a prefabricated structure, it is important to ensure the structure will comply with all local bylaw and building code requirements first. Retail stores like Costco and Home Depot are not obligated to ensure the various prefabricated shed, pergola, and gazebo kits that they sell are compliant with local code requirements. In our experience, many lightweight metal shed and gazebo kits available in Canadian retail stores are not designed to support Canadian snow loads.
This preliminary due diligence is important to identify limits and restrictions applicable to your project early on, allowing you to avoid unnecessary costs and delays to revise designs after drawings have been prepared. Working with a knowledgeable and qualified designer to help you plan your project can prevent unnecessary difficulties down the line.
Owners typically are permitted to design their own project and produce their own drawings. You may find various references online or in books for general design inspiration as well as technical guidance on drafting, standard construction details, and maximum framing spans. That said, building departments set their own submission requirements to ensure drawings are of a high enough quality to be easily reviewed. Your local building department may reject your drawings if the drawings do not meet the building department’s standards. Furthermore, if you are not familiar with applicable regulations, bylaws, and building code requirements you may experience delays in the issuance of your permit. The plans examiner will send you a list of deficiencies to fix anything that is unclear or non-compliant with code or bylaw requirements. You will need to revise and resubmit your drawings until the plans examiner is satisfied that the design meets all necessary requirements before they issue the permit. Hiring a knowledgeable and qualified designer to prepare the drawings for you can prevent unnecessary difficulties with the building permit process.
In general, all drawings must legible, detailed, dimensioned, and drawn to a reasonable standard scale. Most building departments also require drawings to be printed in ink. Hand-drafted drawings in pencil typically would not be accepted, though you may be permitted to submit photocopies. Some building departments require all dimensions to be in metric units, but many will accept either metric or imperial units as long as the drawings are fully dimensioned using one system or the other (mixing up systems of units can lead to confusion and expensive errors on site).
Engineering and architecture are regulated professions. The respective provincial and territorial regulators of these professions maintain public directories of their members, so you can check to ensure an engineer or architect is licensed and in good standing.
Accessory buildings typically do not require design by an engineer or architect and can be designed a licensed technologist. Technologists typically have their own regulator separate from the engineering and architecture regulators in your province.
In Ontario, qualified designers (apart from licensed Professional Engineers and Architects) must have a Building Code Identification Number (BCIN). You can verify the qualifications of a designer using the BCIN directory maintained by the Ministry of Municipal Affairs and Housing.
Most building departments accept permit applications electronically, though a few building departments (e.g. City of Hamilton) still require paper applications. For paper applications you typically need to provide two or more copies of each drawing.
A typical permit application comprises a permit application form, a designer information or declaration form, the required drawing package, and application fees assessed by the building department. Some jurisdictions also require an applicable laws checklist, where the permit applicant has to confirm that they’ve done their due diligence to check whether any other agencies need to approve the project first, and if so, that they’ve obtained the required approvals. Check with your local building department to confirm what you will need to provide with your permit application, including the application fees.
A set of drawings acceptable for a permit application typically would include:
Once the application is accepted, the building department will put your project in the queue to be reviewed. The time between submitting the application to issuance of the permit can vary widely, anywhere from about two weeks to a few months, depending on several factors such as how busy the building department is generally, the complexity of the proposed project, and the quality and completeness of the drawings.
Do you require assistance with your accessory building project? We can help! Contact us at info@ocig.com.
