Have you bought a house and want to add a deck? Or thinking of adding one to your pre-existing home?
Here at Deckly, “Do I need a permit to build a deck?” is one of the most common questions we get. Here’s what you need to know about when a permit is needed, and the risks of building a deck without one in Ontario.
What You Need To Know
Do You Need A Permit To Build A Deck?

- The deck you are planning is attached to or is an extension of your home or any other structure on your property.
- If the deck is not attached to any other structure but is over 30 inches (about 2.5 feet) or higher off of the ground.
- If you are repairing structural aspects to the deck.
- If you are attaching a roof to your pre-built deck.
Applying for a Building Permit
Depending on your region, the exact requirements and information for homeowners to have can differ. However, your residential deck building project will require some basic information universally when applying for a permit.
A detailed drawing of your proposed project will be required. This will usually need to include the scale and size of the yard, where the deck attaches to the house, the length, width and height as well as where you are placing your beams. You will have to obtain and provide other information that may include, guardrail details, size and location of stairs, foundation and materials list, etc.
If your plans meet the codes and your information is up to date your plans should be passed and approved and you can be issued a permit.

Note that a fine will be issued if a deck is built without the proper clearance. The best way to speed up the process for building a deck in Toronto is to call a building official for the design of precise plans. Then your municipality can process your permit without issue.
What Happens If You Build Without A Permit In Ontario?
When applying for a permit you may be required to pay a fee. But the cost is a safeguard against possible charges applied to you if you do not have a permit. According to Ontario’s website, a fine of up to $50,000 could be charged for being found guilty of an offence under the Building Code Act (1992) for a first offence, and up to $100,000 for any following offences. Local rules may matter and change the regulations needed for permits but most codes are universal.
There are many consequences other than just a fee charged:
- If a permit is not acquired when needed, a report will be filed against you and you will be ordered to stop construction and tear it down.
- When it comes time to sell your home, it can be seen that there was no permit issued for the deck. This could affect the time it will take and the cost at which you can sell your home.
- Missed property taxes on the deck can be demanded for things not claimed with a permit.
- If someone were to be injured because of a deck built with no permit, insurance companies would not cover the bill.

All decks must be inspected to determine the safety of the structure. Get a professional to inspect your plans and provide services when needed.
When Permits are not Required for Decks
- It is built at ground level or no more than 600 millimetres (about 24 inches) in height above grade.
- There is no roof above it.
- It is not attached to a house or serving another structure on the lot.
- It is less than 108 square feet.
- It is greater than 4 feet or 1.2 meters from all other existing buildings.
- If the site isn't too close to the property lines.

It is still necessary to make sure that your constructed deck is safe and up to code to avoid failed inspections, removal or fees. Just because the above requirements are met, does not mean the deck should not be inspected by an inspector for other safety measures (like guard rail height and other requirements).
Even though a permit might not be legally required you could still have to report the deck to your city’s office because of zoning bylaws.

Deck building can be done without a permit, except when it exceeds the requirements stated. A deck built without proper steps and precautions can be a great risk to health and safety. A permit may seem like a hassle, but it is worth it financially in the long run and for the security of you and those who will be enjoying your deck.