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, 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 metres* (108 square feet) in 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.

5. 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

6. Energy and environmental building improvements, such as

• roof top storm water 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

7. Construct a deck more than 60 centimetres (24 inches) above ground
8. Construct a retaining wall more than one metre (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
9. Constructing a tent that

• covers more than 60 metres squared (646 square feet); and/or
• is attached to a building; and/or
• is within 3 metres (9 feet 10 inches) from another structure.

10. Demolish or remove all, or a portion of a building
11. Install or reconstruct a chimney or fireplace
12. Install a wood burning stove or fireplace
13. Install or modify heating and or plumbing systems
14. Install a backwater valve
15. Install a backflow prevention device
16. 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, if a change of use is proposed a building permit is required.