Accessory Building Serving a Dwelling Unit

Complete applications for an accessory building serving a dwelling unit must include:

• applicable law approval documents when required
• completed application package
• building permit fees
• building permit application plot plan
• foundation plan
• floor/ framing plans
• elevation drawing
• cross section drawing

The information provided should be used as a sample only to help you with creating your application.

Before you start

Please note that prior to applying for a building permit, it is your responsibility to ensure that all necessary approvals or permits have been obtained from other agencies for any Applicable Law identified in the Ontario Building Code that is relevant to your project.  These approvals are required as part of a complete building permit application package.

Applying for a permit

Please complete Application to Construct or Demolish form and make sure to include a Plot Plan with your submission. We will need the owner's authorization if you are not the property owner.

A Schedule 1: Designer Information Form is required to be filled out for all submissions. Property owners may be exempt from requiring qualifications. All other designers must have appropriate qualifications.

Apply online

You will need to create an account to apply through our online portal. Be sure to have all you documents ready to attach.

Required design documents

Typically requirements are listed below, additional information may be required.

Your plot plan should include:

• Lot lines including dimensions
• Location of proposed accessory building in relation to other structures and lot lines
• Measurements from the accessory building to other structures and lot lines
• Lot area, main building area, proposed building area, and area of all other structures
• Proposed building height
• Location of overhead electrical conductors (if applicable)
• Location of septic systems and the distances to the accessory building (if applicable)
• North arrow and municipal address

Your foundation plan should include:

• Footings and foundation walls or slab-on-ground

Your floor plan should include:

• Wall location and thickness
• Window and door locations including sizes and lintels

Your elevation plan should include:

• The general appearance of the addition from all sides
• Windows and doors sizes
• Exterior wall finish (e.g. siding)

Your cross section plan should include:

• Footing and foundation sizes and depths or slab design;
• Anchor bolt size & spacing
• Floor construction
• Wall construction including stud height
• Roof construction including beams, rafters, joists or trusses, sizes, pitch and direction
• Height from grade to roof peak

Additional design information:

• Engineered stamped truss drawings and truss layout for roofs constructed of pre-engineered roof trusses.
• The floor system design and layout as supplied from the manufacturer when pre-engineered floor joists are used.
• Additional information may be required if plumbing or mechanical systems are proposed.

Required Inspections:

• Excavation prior to pouring footings
• Foundation prior to backfilling
• Framing
• Plumbing and mechanical if required
• Final

Any proposed changes from the approved plans must be approved by a Building Inspector prior to construction. Failure to have the required inspections performed may result in you having to uncover and expose the work for inspection.

Fees

Fees are based on our Building By-Law.

Printable Information Guide

Accessory Buildings Serving a Dwelling Unit Information Guide