If you're building, demolishing, or making significant changes to a building, you will need a building permit.

Building permits ensure you meet:

  • applicable provincial laws,
  • zoning requirements,
  • fire and structural safety standards

The tabs below will help you navigate the process of getting your permit.

 Why building permits are important

Obtaining a Building Permit ensures that your home and other buildings meet these standards in the Ontario Building Code. The Building Code sets out technical requirements for the construction (including renovations) and demolition of buildings, the change of use of existing buildings. The Code is essentially a set of minimum provisions respecting the safety of buildings with reference to public health, fire protections, accessibility and structural sufficiency. Its primary purpose is the promotion of public safety through the application of appropriate uniform building standards.

The City of Cornwall strives to promote a safe and healthy community for its residents.  This extends to the private and publicly-owned buildings with the City. 

Building Officials adhere to a Code of Conduct and are responsible for overseeing and inspecting that the Building Code is followed and implemented. 

Compliance with the Building Code is achieved through mandatory inspections for building permits, demolitions, investigations of work performed without permits. 

A building permit must be refused by the City if an owner's construction will not meet Ontario's Building Code. The Ontario Building Code sets out mandatory minimum standards for structural, health, fire safety and accessibility, and there is no appeal or variance permitted.

The Building Code also requires that permit plans be prepared by a provincially qualified designer, or by an architect or professional engineer. Your designer is responsible to ensure the design meets the building code.

The Building Code permits knowledgeable homeowners to prepare permit plans for their own house, provided they meet these same construction standards.

The City does not provide design services.

Projects that require a permit

A building permit is required before starting a construction, demolition or renovation project, other than the exceptions listed below. This is provided for general guidance and is not an all-encompassing listing. For advice on whether your project requires a permit, contact our Permit Technician at 613-930-2787 ext 2355. 

It is the property owner's responsibility to ensure that a building permit is obtained when required. You may authorize your contractor or designer (for example) to apply for the permit, but as the owner you must ensure that you have the permit prior to starting work. 

New Construction projects that require a permit:

  • Any new building greater than 15m2 (160 ft2) in size (the area of the building's footprint)
  • Any new building that contains plumbing, irrespective of size
  • Any addition to an existing building, irrespective of size
  • Concrete porches
  • Decks (exceptions may apply)
  • Detached or attached garages and carports
  • Solariums
  • Addition of a dormer
  • Sunrooms
  • Installing or changing a fence or a swimming pool fence enclosure
  • Tents (645 sq. ft / 60 m2 more ground area)
 Demolition and alterations that require a permit:
  • Demolishing any building greater than 15m2 (160 ft2) in size
  • Adding, removing or altering a structural wall or column
  • Adding, removing or altering a non-loadbearing partition
  • Changing the use of a building
  • Installing a basement entrance
  • Relocating a Building
  • Changing a fireplace from gas to wood or solid fuel burning
  • Roughing in a bathroom or washroom
  • Installing a fireplace or wood stove
  • Renovating a dwelling to provide a full basement
  • Construction separate rooms in a basement
  • Installing an accessory apartment
  • Installing any new plumbing piping
  • Repairing or installing an on-site sewage system
  • Connecting to municipal sanitary and storm sewers
  • Installing a new furnace utilizing a new fuel source
  • Installing an exterior sign
  • An underground sprinkler system connected to building plumbing
  • Installing a solar hot water system
  • Recycling grey water to reduce water use
  • Roof-mounted solar photovoltaic panels
  • Replacing an exterior wall or cladding
A building permit is required for construction whether the work is on the interior or the exterior of the building or dwelling. There is no exemption for a building permit when performing construction solely within or inside a dwelling. You don't need a Building Permit for the following residential projects:
  • Constructing detached accessory buildings less than 15m2 (160 sq. ft.) in area*
  • Replacing plumbing fixtures or water heaters
  • Replacing a furnace or adding air conditioning units or a heat pump
  • Electrical projects (Consult the Electrical Safety Authority)
  • Kitchen or bathroom cupboards
  • Painting and decorating
  • Maintenance and repairs
  • Replacing windows or doors (same size openings)
  • Replacing roofing or shingles
  • Retaining walls less than 1 meter in height
  • Sidewalks, planters and landscaping
  • Garden pergolas and gazebos that do not have a solid roof

Application Forms

 How to apply for a Building Permit

Visit Building & By-law Division at the Cornwall Civic Complex (Second Floor) at 100 Water Street East or give us a call at (613) 930-2787 ext. 2355 to obtain a building permit application. Applications and additional information can also be obtained in the Department Forms box on this page (above).

Please submit your application at permits@cornwall.ca.

The permit application requires information about the project. You will be asked to document who will perform the work, what work will be done, where the work will be done, and how the work will be done.

Digital scaled drawings, plans or other documentation of the proposed work will have to be submitted for review. Included with the submission, the plans must have the designer's B.C.I.N. registration number, except when a homeowner is preparing their own drawings or for accessory structures under 55m2 (592 sq. ft).

Cost of a Building Permit

Building permit fees depend on the floor area and type of building being constructed or altered.

Typical building permit fees for residential buildings are based on area (refer to the Fees and Charges By-Law #2018-089, for a complete listing. There is a $262.00 minimum permit fee.

Typical building permit fees for non-residential buildings are calculated based on the estimated construction value. The current building permit fee is $19.74 per $1,000.00 of construction value.

For example, if construction for a project is worth $800,000 the building permit fee would be equal to: 
$19.74 X $800,000.00 / $1,000.00 = $15,792.00.

2024 Fee Schedule

A By-law respecting Construction, Demolition and Change of Use Permits (Including Fees)


Each major phase of construction must be inspected by our Building Officials to make certain the work conforms to the Building Code, the building permit and the approved plans.

The mandatory inspections required for your project will be indicated on the permit. It is your responsibility to ensure that either you or your contractor contacts the city to request an inspection at least 48 hours before work proceeds from one inspection stage to the next. 

Zoning and Other Applicable Laws

A building permit cannot be issued if an owner's site plan and building proposal does not meet City zoning standards, including land use, setbacks from property lines and maximum lot coverage. If you cannot meet all zoning requirements because of site restrictions, you may apply for exemption through the Committee of Adjustment or a zoning by-law amendment. These processes must be completed before a building permit can be considered.

Use our online zoning search tool to determine the zoning restrictions that apply to your property. Click here to access the tool.

In certain cases other laws will apply to a project and must be completed before a building permit can be issued. The laws include site plan approval under the Planning Act, heritage approvals, conservation authority permits and others.

Use our online property information tool (click here to access the tool) and our applicable law checklist [PDF] to determine the other applicable laws that apply to your property. If they do, it is recommended that you complete these approvals before applying for your building permit.

 Septic System Permits 

The City of Cornwall has entered into an agreement with the South Nation Conservation Authority for the enforcement of Part VIII of the Ontario Building Code - Private Sewage Systems.  As such all Sewage Permit applications will be submitted directly to the South Nation Conservation; please coordinate with your Sewage System Designer. 

The South Nation Conservation issues permits and services related to severances, land development, new construction and inspections of private sewage systems. Privately owned sewage systems, including septic tanks and leaching beds, require a permit for installation or alteration under the Ontario Building Code. Proper operation and maintenance of your private sewage system is also required under this Ontario Building Code jurisdiction.

The South Nation Conservation is located at 38 Victoria Street in Finch, Ontario and can be reached at:

Telephone: 613-984-2948 or Toll Free: 1-877-984-2948

More information is available on South Nation Conservation's website.

Ministry of Municipal Affairs & Housing Guides

 Add a second unit in your House
 The MMAH Guide to adding a second unit in your house is available online.
 Build or buy a Tiny Home
 The MMAH Guide to Building of Buying a Tiny Home is available online.
 Building a Modular House
 The MMAH Guide to Building a Modular House is available online.
Department of Planning, Development and Recreation
Building & By-Law Division
Cornwall Civic Complex
100 Water Street East, 2nd Floor
Cornwall, Ontario K6H 6G4
Tel:      (613) 930-2787
Fax:     (613) 932-3236
Ext # 2355  Permit application and general code questions
Ext # 2310  Schedule a Fence Permit inspection
Ext # 2323  Permit inquiries and to schedule Building Permit inspections
Ext # 2312  Zoning questions

Please click here to submit a complaint with regards to building.

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