---
title: Duncan permits for decks, sheds, carports and garages
question: "Do I need a permit for a deck, shed, carport, or garage?"
place: Duncan, British Columbia, Canada
place_path: ca/bc/duncan
category: Building, renovating and your property
owner: municipal
owner_body: City of Duncan
sources_read: 2026-11-05
review: machine_checked
canonical: "https://govhandbook.com/ca/bc/duncan/deck-shed-garage-permit/"
json: "https://govhandbook.com/ca/bc/duncan/deck-shed-garage-permit.json"
---

# Duncan permits for decks, sheds, carports and garages

**Question:** Do I need a permit for a deck, shed, carport, or garage?

**Short answer:** 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.

**Who handles it:** Municipal (City of Duncan, https://duncan.ca)  
**Cost:** Plan review fee plus building permit fee; see the building-permit-fees answer. Building without a permit costs double the permit fee.  
**How long:** Not stated on the City's pages.  
**Where:**
- Phone: Development Services (Building Inspector), 250-746-6126
- Email: Development Services, developmentservices@duncan.ca
- In person: City Hall, 200 Craig Street, Duncan, BC V9L 1W3

## 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.
  - Source: [Do I Need a Building Permit?](https://duncan.ca/download/do-i-need-a-building-permit/)
  - Official wording: "Construct a new accessory building or" … "structure larger than 8m2" … "Construction of a new accessory building or" … "structure 8m2 or less within the required setbacks"
  - Check: wording matched the official text retrieved 2026-11-06
- **Decks:** Building permit needed to construct, cover or enclose porches and exterior decks. The City's list gives no height threshold for decks.
  - Source: [Do I Need a Building Permit?](https://duncan.ca/download/do-i-need-a-building-permit/)
  - Official wording: "Construct, cover, or enclose porches" … "and exterior decks"
  - Check: wording matched the official text retrieved 2026-11-06
- **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.
  - Source: [Do I Need a Building Permit?](https://duncan.ca/download/do-i-need-a-building-permit/)
  - Official wording: "Construct a new accessory building or" … "structure larger than 8m2" … "Renovate or add on to an existing"
  - Check: wording matched the official text retrieved 2026-11-06
- **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.
  - Source: [Zoning Bylaw No. 3166, 2017 (PDF, consolidated to August 24, 2026), s. 3.3.2, 3.3.4, 3.11.1, 4.3.1](https://duncan.civicweb.net/document/175322)
  - Official wording: "Accessory 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"
  - Check: wording matched the official text retrieved 2026-11-06
- **Bylaw:** Zoning Bylaw No. 3166, 2017 (consolidated to August 24, 2026); Building Bylaw No. 3254, 2026
  - Source: [Zoning Bylaw No. 3166, 2017 (PDF, consolidated to August 24, 2026), Part 3 and Part 4](https://duncan.civicweb.net/document/175322)
  - Official wording: "City of Duncan Zoning Bylaw No. 3166"
  - Source: [City of Duncan bylaws folder (Building Bylaw No. 3254, 2026), Bylaw list](https://duncan.civicweb.net/filepro/documents/37448)
  - Official wording: "Building Bylaw No. 3254, 2026"
  - Check: wording matched the official text retrieved 2026-11-06

## 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](https://duncan.civicweb.net/filepro/documents/37448) could not be read for this answer.

## Steps

1. Find your zone on the City's zoning map and read the accessory building rules in the [Zoning Bylaw](https://duncan.civicweb.net/document/175322).
2. Phone Development Services at 250-746-6126 if you are near the 8 m² line or unsure.
3. Submit the Building Permit Application and pay the fees.
4. 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

- [Do I Need a Building Permit? (PDF)](https://duncan.ca/download/do-i-need-a-building-permit/)
- [Building Permit Application](https://duncan.ca/download/building-permit-application-2/)
- [Zoning Bylaw No. 3166 (PDF)](https://duncan.civicweb.net/document/175322)

## Related questions

- [Duncan building permits: when you need one and how to apply](https://govhandbook.com/ca/bc/duncan/building-permit.md)
- [Duncan building permit fees](https://govhandbook.com/ca/bc/duncan/building-permit-fees.md)
- [Duncan zoning: find your zone and what it allows](https://govhandbook.com/ca/bc/duncan/zoning-lookup.md)
- [Duncan fence rules: permits and height limits](https://govhandbook.com/ca/bc/duncan/fence-rules.md)
- [Duncan secondary suite and carriage house rules](https://govhandbook.com/ca/bc/duncan/secondary-suite.md)

## The same question elsewhere

- [Deck and shed permit thresholds in British Columbia, by municipality](https://govhandbook.com/ca/bc/deck-shed-garage-permit.md)
- [North Cowichan](https://govhandbook.com/ca/bc/north-cowichan/deck-shed-garage-permit.md)
- [Ladysmith](https://govhandbook.com/ca/bc/ladysmith/deck-shed-garage-permit.md)
- [North Saanich](https://govhandbook.com/ca/bc/north-saanich/deck-shed-garage-permit.md)
- [Lake Cowichan](https://govhandbook.com/ca/bc/lake-cowichan/deck-shed-garage-permit.md)
- [Sidney](https://govhandbook.com/ca/bc/sidney/deck-shed-garage-permit.md)
- [Central Saanich](https://govhandbook.com/ca/bc/central-saanich/deck-shed-garage-permit.md)

## Sources

- [Do I Need a Building Permit? (PDF), City of Duncan](https://duncan.ca/download/do-i-need-a-building-permit/) (read 2026-11-05)
- [Zoning Bylaw No. 3166, 2017 (PDF, consolidated to August 24, 2026)](https://duncan.civicweb.net/document/175322) (read 2026-11-05)
- [City of Duncan bylaws folder (Building Bylaw No. 3254, 2026)](https://duncan.civicweb.net/filepro/documents/37448) (read 2026-11-05)
- [Bylaw Notice Enforcement Bylaw (PDF), City of Duncan](https://duncan.civicweb.net/document/181059) (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. Gov Handbook is an independent guide, not affiliated with City of Duncan. How answers are checked: https://govhandbook.com/methods/ · Canonical page: https://govhandbook.com/ca/bc/duncan/deck-shed-garage-permit/_