Deck Builders & Custom Decks in Ottawa

The 600 mm rule, and the two ways it applies

1. Attached or adjacent to the house: a permit is required if the walking surface is more than 600 mm, about 24 inches, above the adjacent grade. The deck's area does not matter here. A small landing off a side door counts.
2. Freestanding, out in the yard: a permit is required if the walking surface is larger than 10 square metres, roughly 108 square feet, and more than 600 mm above the adjacent grade. Both conditions have to be true.
3. Any elevated deck that provides the principal access to a building needs a permit whatever its area.

Grade is measured beside the deck, not at the house wall, so a yard that falls away can put one end of a low deck over the line while the other end sits under it.

Zoning is a separate question from the permit

A permit says the structure meets the Ontario Building Code. It does not say the deck is allowed where you want to put it. Setbacks to lot lines, lot coverage and height come from the Zoning By-law, and the City's Development Information Officers answer those. They take inquiries at 613-580-2424 extension 23434 and through 3-1-1, and reply within two to three business days.

Ask that question before the design is final. A deck that has to move two feet after the drawings are done is a redraw and a resubmission.

Three inspections, and 48 hours of notice

The City inspects a permitted deck at excavation and foundation stage, at framing, and at completion. The foundation inspection happens on in-situ piers and pads before backfill, so once a hole is filled the evidence is gone and the work may have to be uncovered again.

Book each inspection 48 hours ahead, and keep the permit plans on site. The inspector's name and phone number are printed on the permit itself. The City's approved service level puts a first review of a deck application at five business days.

Who is on the hook

You can authorise a contractor or designer to apply for the permit, but the City is explicit that the owner and the builder are equally liable under the Ontario Building Code Act. Ask to see the issued permit before any material is delivered, rather than taking a start date as evidence that one exists.

A permit also has a clock on it. Construction has to seriously commence within six months of issue or the permit can be revoked, and a job substantially suspended for more than a year can lose its permit too.