Whether your deck needs a permit in Ottawa depends on how high the walking surface sits above the ground, whether the deck touches the house, and how big it is. The City names three cases, and this post gives each one in the City’s own terms, with no rounding, then goes through what the application and the inspections involve.
Every number below comes from the City of Ottawa’s pages, the province’s building rules or Ontario Dig Authority. Fees and rules change, so check the City’s pages before you rely on them.
What is the general rule
Ottawa’s deck page says that under the Building Code Act, a building permit is required for the construction of a new building, an addition, or alteration of any building or structure with a building area of over 10 square metres (approximately 108 square feet).
It then gives three cases for decks.
When does an attached deck need a permit
If the deck is adjacent to or attached to the house and its walking surface is more than 600 mm (24 in.) above the adjacent grade, a permit is required. The page says this applies regardless of the deck’s walking surface area.
When does a deck that gives access to a building need a permit
If the deck is an elevated deck providing principal access to a building, a permit is required. The page says this applies regardless of the deck’s walking surface area.
When does a freestanding deck need a permit
If the deck is independent from the house, such as one in the middle of the yard, the page gives two tests together. The deck has a walking surface greater than 10 square metres (approximately 108 square feet) in area and its walking surface is more than 600 mm (24 in.) above the adjacent grade. When both are true, a permit is required.
What if your deck fits none of the three
The page lists no fourth case. If your deck sits outside all three, ask the City before you assume it needs nothing.
How does zoning fit in
A permit involves zoning as well as the building code. The page says a Development Information Officer can advise on zoning regulations impacting your sundeck design, particularly setbacks to lot lines, and gives 3-1-1 as the number to call.
Zoning is also changing. The City’s zoning page says Zoning By-law 2026-50 was enacted by City Council on March 11, 2026. Building permit applications deemed complete on March 11, 2026 or after must comply with the provisions in Zoning By-law 2008-250 and the new Zoning By-law 2026-50, with the most restrictive provisions from both by-laws applying.
The page also says its consolidation of the zoning by-law was current to June 24, 2026. This post gives no setback figures for that reason. Ask the Development Information Officer for your area what applies to your lot.
What does an application need
The City’s page lists three things. You need the Application for a Permit to Construct or Demolish, the applicable fee, and a complete set of detailed plans that are legible and drawn to a conventional scale. The page links a checklist and a sample plan.
It says deck applications can be submitted online through the Building, Planning and Land Development online application and permitting portal on My Service Ottawa. It also says Building Code service counters are open for personal services by appointment only.
What does the permit cost
Ottawa’s Comprehensive Building Code Fee Schedule, dated January 1, 2026, lists a Permit to Construct for all other construction at $12.75 per $1,000 or part thereof of the assessed valuation of the work, with a minimum fee of $117.00.
The schedule says fees are due when you submit a building permit application, and that they may change without notice. It says you can pay with cheque, debit card, bank draft or money order.
Ask the City which fee line applies to your deck, since the line quoted here is the one for all other construction.
What happens if you start before the permit
The fee schedule lists an administrative surcharge of 50 per cent of the permit fees, up to a maximum of $10,000, when construction begins before a permit is issued. Wait for the permit before you dig.
How long does the first review take
The City gives an approximate timeline of 5 business days for the first review, based on the City Council approved enhanced service level. The page gives the time for the first review only, so leave room for questions and for your contractor’s schedule.
Which inspections does a deck get
The page says that at key stages of building construction, your work must be inspected to ensure that the completed construction complies with the Ontario Building Code. It names three inspections for a deck.
- Footing and foundation, for in-situ piers and pads, before backfill.
- Framing, at completion of structural framing and guards.
- Final, at completion of the deck framing, stairs and guards.
The permit plans and specifications must be on site and made available to the Building Inspector at the time of inspection. The City says to book inspections 48 hours in advance.
It also says that failure to have the appropriate inspection performed may result in your having to uncover and expose the work for inspection, or other orders issued.
The fee schedule lists a re-inspection fee of $100 per inspection for single detached, semi-detached, row house or townhouse dwelling units.
What does the building code ask of the deck itself
The City’s page says the Ontario Building Code outlines the minimum requirements for elements such as joist size, beam size, foundation requirements and guard requirements. The code in force is the 2024 edition, Ontario Regulation 163/24, which came into force on January 1, 2025.
Division B, Article 9.8.8.1. requires a guard on each side of a surface such as an exterior landing, porch or raised walkway that is not protected by a wall, for the length where the difference in elevation is more than 600 mm between the walking surface and the adjacent surface within 1.2 m.
Article 9.8.8.3. says guards are generally not less than 1070 mm high. Exterior guards serving not more than one dwelling unit are not less than 900 mm high where the walking surface is not more than 1800 mm above the finished ground level.
Article 9.12.2.2. sets the minimum depth of foundations below finished ground level by soil type and drainage, and for some combinations of soil and drainage the foundation has to go below the depth of frost penetration. Ask your contractor which applies to your soil.
Do you need to call before you dig
Ontario Dig Authority, formerly known as Ontario One Call, says locates are required for any project that breaks ground, no matter the size or depth of the excavation. It says to submit a locate request at least 5 business days before you dig, and that the service is free and required by law.
A footing is an excavation, so a deck with footings is covered.
What should you settle before you apply
- How high the walking surface will sit above the adjacent grade, since 600 mm is the line the City uses.
- Whether the deck attaches to the house or stands on its own, since the area test of 10 square metres applies to the freestanding deck.
- Which lot-line limits your zoning sets, from the Development Information Officer.
- A set of plans that are legible and drawn to a conventional scale.
Henike Contracting builds floating decks and decks on concrete footings in the Ottawa area. Bring the walking surface height and a measured sketch to the first conversation.