Accessory structures: Garages, sheds and gazebos

Building permits are required for accessory structures such as detached garages and gazebos over 10 square metres (107 square feet). Building permits are also required for all accessory structures that contain plumbing, regardless of their size.

Building permits are not required for open-roofed pergolas that are at least 50% open and can not support any accumulated snow (e.g. 2×4’s spaced 12″ apart). Building permits are also not required for detached, one-storey storage sheds that do not exceed 15 square metres (161 square feet).

If you are adding a dwelling unit to a detached building, refer to Additional residential dwelling units.

How to apply for an accessory structure permit

Requirements to obtain a building permit for accessory structures

Building permit applications are required to be submitted electronically through the Guelph Permit and Application System. As a registered user, you can check the status of your permit, pay fees and book inspections online. Ensure all required drawings are ready to upload in PDF format before starting your online application.

All drawings listed below must be included and must be drawn to a recognizable scale (e.g. ¼ inch equals 1 foot). Partial floor plans or photos will not be accepted. Single line drawings are also not acceptable. Drawings must illustrate wall thicknesses. The sample site plan and drawings included in the handout package are for reference only.

  • A survey or site plan illustrating the lot width and depth, the location of the proposed and existing accessory structure(s) including setbacks to all property lines, the size of the proposed and existing accessory structure(s) on the property)
  • Foundation Plan
  • Floor plan/roof framing plan
  • All side elevations
  • Cross-section


Once your building permit application is deemed complete, you will be notified of the applicable building permit fee. Please visit for the current fee schedule.


All accessory buildings must comply with Zoning regulations regardless of whether a building permit is required or not. These requirements include:

  • Cannot be in a front or required exterior side yard
  • Must be setback a minimum of 0.6 metres (2 feet) from the property line
  • Cannot occupy more than 30% of the yard it is located in
  • Cannot exceed 3.6 metres (11 feet, 10 inches) in height and;
  • Cannot exceed 70 square metres (753 square feet) in area