Do I Need Building Permit?

Under the Building Code Act, a building permit is required for the construction and/or demolition of a new building, an addition, or material alteration of any building or structure. The following is a list of common projects that require or do not require a building permit:

When is a Building Permit Required?

As the building owner, you are ultimately responsible for complying with all building requirements. Failure to obtain building permits can result in costly construction delays, legal action and/or the removal of work already completed. The following is a list of common projects that require a building permit. The list is not exhaustive. If you have any questions please contact Toronto Building.

  1. Construct a new building
  2. Construct an addition to an existing building, such as:
    • Second or third story additions

    • Attached garages/carports

    • Sunrooms

    • Solariums, porches, and decks

  3. Make structural or material alterations, such as: 
    • Adding or removing walls (i.e., changing room sizes and/or uses)

    • New windows or doors where there were none before

    • Enlarging or relocating existing windows or doors

    • Enclosing an existing deck, porch or patio of any size.
  4. Construct an accessory structure larger than 10 square meters* (108 square feet) in an area, such as: 

  • Detached Garage
  • Workshop

  • Garden shed

  • Carport

  • Pool house or cabana

*Note: If you are constructing an accessory structure and it is attached to an existing building and/or has plumbing, regardless of its size, a building permit is required.

Finishing a basement, if the work proposed includes any of the following, 

  • Structural or material alterations
  • Installing or modifying heating and/or plumbing systems
  • Excavating and/or constructing foundations
  • Basement underpinning
  • Constructing a basement entrance
  • Adding a second suite

Energy and environmental building improvements, such as:

  • Roof top stormwater retention systems
  • Green roofs
  • Structures used in the support of a wind turbine generator, with a rated output of more than 3kW
  • Solar projects, such as, installation of solar collector systems and solar hot water systems
  • Construct a deck more than 60 centimeters (24 inches) above ground
  • Construct a retaining wall more than one meter (3 feet 3 inches) in height, provided the retaining wall is on, or adjacent to public property (including streets), building entrances and on private property accessible to the public
  • Constructing a tent that covers more than 60 meters squared (646 square feet) and/or is attached to a building is within 3 meters (9 feet 10 inches) from another structure
  • Demolish or remove all, or a portion of a building
  • Install or reconstruct a chimney or fireplace
  • Install a wood burning stove or fireplace
  • Install or modify heating and/or plumbing systems
  • Install a backwater valve
  • Install a backflow prevention device

Change a building's use (i.e. from residential to office, or single dwelling unit house to multi-dwelling unit house) Even if no construction is proposed, a change of use is proposed a building permit is required.

When is a Building Permit Not Required?

The following are examples of work which do not require a building permit and are not subject to the provisions of the building code. However, please note that this list is not exhaustive and judgment should be used, depending on the situation and circumstances associated with the project. Even if a building permit is not required, compliance with the Zoning Bylaw is required.

An uncovered platform (i.e. deck) attached to a residential building provided:

  • Its finished deck level is not more than 60 cm (24 inches) above the adjacent finished grade; and/or
  • It does not form part of an exit required under the building code; and
  • Complies with the Zoning Bylaw.

Installing a skylight in an existing building provided:

  • The building is a house or small building (3 storeys or less) and;
  • The installation does not require the removal of more than one rafter, joist or other similar structural member (with the exception of a truss)

Re-cladding of a house or small building (3 storeys or less) with non-combustible material other than brick, stone or veneer

The replacement of windows or doors provided:

  • There is no change in the location or size of the window and/or door
  • The structural support for the opening (i.e. lintel) is not affected
  • A new exit is not created

Replacing a furnace or boiler in a house

  • The installation of additional cooling systems, gas fireplaces, air cleaners, in-line humidifiers, or hot water tanks in a house
  • Repairing and replacing plumbing fixtures
  • Replacing existing roofing material, provided no structural work is required

Finishing a basement of a house, if:

  • The work does not include structural or material alterations
  • No additional dwelling unit(s) is (are) created (i.e. a second unit)
  • The work does not include the installation of new plumbing
  • Undertaking waterproofing repairs to a basement;
  • Installation of cabinetry and millwork

Plastic sheet covered accessory structures (i.e. snow canopies, driveway tents, automotive canopy) do not require a building permit if installed on or after October 15th and are removed on or before April 15th. Compliance with the Zoning Bylaw is required.

Constructing a retaining wall that is on private property, not accessible to the public and/or where the height is less than 1 meter in height at any location.

A building permit is not required to install a sump pump.

The above information has been taken from