Deck permit when the house has three units in Ottawa?

A deck on a house with three or more units falls outside the homeowner design exemption, so you will need a BCIN designer, an architect or an engineer to take design responsibility for the permit drawings. That is the first practical difference from a single-family home.

The City of Ottawa's permit triggers apply the same way regardless of how many units the building has. A permit is required if the deck is attached to the house and its walking surface is more than 600 mm (24 in.) above adjacent grade, or if it is an elevated deck providing principal access to the building, whatever its size. A freestanding deck in the yard needs a permit only if it is both more than 10 square metres (approximately 108 square feet) in area and more than 600 mm above grade.

The homeowner design exemption is where the unit count changes things. The City explains that a homeowner may take design responsibility for drawings related to their own house, but that exemption does not apply where more than two dwelling units exist in the building. With three units, Schedule 1 of the permit application must name a BCIN designer, an architect or an engineer. That person takes design responsibility for the drawings.

A few other things follow from this:

• The permit application still goes through the My ServiceOttawa portal, with a complete set of scaled, dimensioned drawings: a site plan, a foundation and framing plan, and elevations.
• The City's fee is $12.75 per $1,000 of assessed valuation (materials, labour, overhead and professional fees combined), with a minimum of $117.
• The three inspections still apply: Excavation/Foundations before backfill, Framing at completion of structural framing and guards, and Final at completion. Book each one 48 hours in advance.
• Both Zoning By-laws 2008-250 and 2026-50 apply to applications deemed complete on or after March 11, 2026, with the most restrictive provisions from each winning. Setbacks and yard projections depend on the zone, so confirm the rules for the specific lot with the City.
• If the deck uses composite or PVC decking rather than conventional lumber, the permit application needs a CCMC or BMEC material testing report.

If any footing work is involved, a locate request through Ontario One Call must go in at least five business days before anyone digs. That step applies whether a contractor or the owner does the digging.

The most useful question to put to your designer or engineer before they start the drawings is whether the deck's connection to the building, given that it has three units, triggers any Part 4 structural design requirements beyond the standard Part 9 prescriptive rules.