Duncan permits for decks, sheds, carports and garages
Do I need a permit for a deck, shed, carport, or garage?
In the City of Duncan, porches and exterior decks need a building permit, and so does an accessory building or structure larger than 8 m² (sheds, garages, carports). One of 8 m² or less within the required setbacks does not. Zoning limits apply either way.
Key facts
| Sheds | A new accessory building or structure larger than 8 m² needs a building permit. One of 8 m² or less within the required setbacks does not.Do I Need a Building Permit? · Wording matched the official text retrieved 2026-11-06Official wordingConstruct a new accessory building or structure larger than 8m2 Construction of a new accessory building or structure 8m2 or less within the required setbacks |
|---|---|
| Decks | Building permit needed to construct, cover or enclose porches and exterior decks. The City's list gives no height threshold for decks.Do I Need a Building Permit? · Wording matched the official text retrieved 2026-11-06Official wordingConstruct, cover, or enclose porches and exterior decks |
| Garages and carports | A garage or carport is an accessory building: building permit needed if larger than 8 m². Attached to the house, it is an addition or renovation, which needs a permit.Do I Need a Building Permit? · Wording matched the official text retrieved 2026-11-06Official wordingConstruct a new accessory building or structure larger than 8m2 Renovate or add on to an existing |
| Zoning limits | Low Density Residential: accessory buildings must be 1.2 m from the house; max height 5 m (7.5 m with a detached suite on the second storey); setbacks front 6 m, rear 1.5 m, interior side 1.5 m, exterior side 3 m; parcel coverage 50%. One accessory building under 10 m², on the ground, up to 3 m high may be 1 m from side and rear lines. No dwelling use or bathing facilities unless a permitted detached suite.Zoning Bylaw No. 3166, 2017 (PDF, consolidated to August 24, 2026), s. 3.3.2, 3.3.4, 3.11.1, 4.3.1 · Wording matched the official text retrieved 2026-11-06Official wordingAccessory buildings, regardless of zone, must be sited at least 1.2 m from a principal may be sited not less than 1 m from an interior side or rear parcel line the accessory building or structure has a gross floor area less than 10 m2 the height of the accessory building or structure does not exceed 3 m 5 m for buildings without a detached secondary suite 7.5 m for buildings with a detached secondary suite on Maximum Parcel Coverage 50% contain bathing facilities |
| Bylaw | Zoning Bylaw No. 3166, 2017 (consolidated to August 24, 2026); Building Bylaw No. 3254, 2026Zoning Bylaw No. 3166, 2017 (PDF, consolidated to August 24, 2026), Part 3 and Part 4; City of Duncan bylaws folder (Building Bylaw No. 3254, 2026), Bylaw list · Wording matched the official text retrieved 2026-11-06Official wordingCity of Duncan Zoning Bylaw No. 3166 Building Bylaw No. 3254, 2026 |
How it works
The City of Duncan's checklist says a building permit is needed to construct, cover or enclose a porch or exterior deck, and to build an accessory building or structure larger than 8 m². The City's list gives no height threshold for decks. A garage or carport is an accessory building, so it needs a permit if larger than 8 m². Attached to the house, it is an addition, which also needs a permit. Zoning separately controls size and distance from property lines, so check both. The City's current Building Bylaw could not be read for this answer.
Steps
- Find your zone on the City's zoning map and read the accessory building rules in the Zoning Bylaw.
- Phone Development Services at 250-746-6126 if you are near the 8 m² line or unsure.
- Submit the Building Permit Application and pay the fees.
- Build only after the permit is issued.
Good to know
- In the Low Density Residential zone, accessory buildings must be at least 1.5 m from rear and interior side lines, 3 m from an exterior side line and 6 m from the front line, and no more than 5 m high (7.5 m with a detached suite on the second storey).
- Parcel coverage in that zone is 50%.
- One accessory building under 10 m², on the ground and up to 3 m high, may be 1 m from side and rear lines.
- An accessory building must be 1.2 m from the house. It may not be used as a dwelling or have bathing facilities unless it is a permitted detached suite.
- Pools, hot tubs and spas deeper than 0.5 m, and pool fences, also need a permit.
- Other zones have their own tables. Unlawful setbacks, parcel coverage or height are each a $200 bylaw notice.
Official forms and pages
The same question in other places
North Cowichan · Ladysmith · North Saanich · Lake Cowichan · Sidney · Central Saanich
Deck and shed permit thresholds in British Columbia, by municipality →
Sources
- Do I Need a Building Permit? (PDF), City of Duncan (read 2026-11-05)
- Zoning Bylaw No. 3166, 2017 (PDF, consolidated to August 24, 2026) (read 2026-11-05)
- City of Duncan bylaws folder (Building Bylaw No. 3254, 2026) (read 2026-11-05)
- Bylaw Notice Enforcement Bylaw (PDF), City of Duncan (read 2026-11-05)
Checked by script, not yet by a person: the official wording behind 5 of 5 facts was matched to the official text. How answers are checked.