Coquitlam secondary suite and carriage house rules

Can I add a secondary suite or a carriage house?

Coquitlam, British ColumbiaChecked against official textSources read 2026-11-05

Short answer

Yes, in many zones. Coquitlam's Zoning Bylaw treats a secondary suite, carriage house or garden cottage as an accessory dwelling unit, counted toward the zone's limit on units per lot (R-1 up to four; RS-2 one, inside the house). A suite needs a building permit. Call Building Permits at 604-927-3441.

Key facts

Secondary suite allowed	Yes. A secondary suite is an 'accessory dwelling unit' and counts as a dwelling unit toward the zone's limit: R-1 and R-2 up to four per lot (R-2 three on lots 280 m² or less); R-3 two principal plus two accessory; RS-2 one accessory unit, inside the single-detached house.Sources differ: The City's Secondary Suites FAQ (older wording) says a suite may only be in a single family dwelling and only one per dwelling; the current Zoning Bylaw counts accessory dwelling units within the zone's unit limit. Zoning Bylaw followed. Zones other than RS-2 and R-1 to R-4 were not checked.Zoning Bylaw 3000, Parts 1 and 2 (definitions), s. 201 definitions; Zoning Bylaw 3000, Part 10 Low Density Residential Zones, s. 1001-1002; Secondary Suites FAQs, FAQ: Can my home contain a secondary suite · Wording matched the official text retrieved 2026-11-06 Official wording may include secondary suite, carriage A maximum of four dwelling units are permitted on a lot. (b) A maximum of one accessory dwelling unit is permitted on a lot. An accessory dwelling unit must be contained within a principal building for a single- A maximum of two principal dwelling units and two accessory dwelling units are A single family dwelling may not contain more than one secondary suite.
Coach house or garden suite allowed	Yes in the R zones: an accessory dwelling unit may be a carriage house or garden cottage, and a building holding only an accessory unit counts as a principal building. In RS-2 the accessory unit must be inside the house.Zoning Bylaw 3000, Parts 1 and 2 (definitions), s. 201 definitions; Information for Building Small-Scale Multi-Unit Housing, Intro; Zoning Bylaw 3000, Part 10 Low Density Residential Zones, s. 1001(9) · Wording matched the official text retrieved 2026-11-06 Official wording house, garden cottage but excludes lock-off unit. that do not contain a principal dwelling unit and only contain an accessory dwelling unit single-detached houses, backyard suites, duplexes, triplexes, fourplexes and multiplexes An accessory dwelling unit must be contained within a principal building for a single-
Limits	Dwelling units per lot: R-1 four (floor area ratio 0.65 for one or two units); R-2 four, or three on lots of 280 m² or less; R-3 two principal plus two accessory; RS-2 one accessory unit. No owner-occupancy rule found.Zoning Bylaw 3000, Part 10 Low Density Residential Zones, s. 1002-1004 · Wording matched the official text retrieved 2026-11-06 Official wording A maximum of four dwelling units are permitted on a lot. One or Two 0.65 maximum of three dwelling units are permitted on the lot. A maximum of two principal dwelling units and two accessory dwelling units are (b) A maximum of one accessory dwelling unit is permitted on a lot.
Parking	Small-scale residential: 1 space per dwelling unit under 79 m², 1.5 spaces for 79 to 158 m², 2 spaces over 158 m². In RS-2, A-3 and legacy zones: 1 space per accessory dwelling unit. No residential parking is required in Transit-Oriented Areas.Zoning Bylaw 3000, Part 7 Off-Street Parking and Loading, s. 706(1) · Wording matched the official text retrieved 2026-11-06 Official wording 1 space per dwelling unit that measures 1.5 spaces per dwelling unit that 1 space per accessory dwelling unit Despite Sub-section 706(1)(a), off-street parking spaces are not required for the
Permits	A building permit is required for a secondary suite or coach house. A Development Permit may also be needed if the property is in a Development Permit Area; contact Planning and Development at 604-927-3430.Secondary Suites FAQs, FAQ: Can my home contain a secondary suite; Building & Construction; Building Projects - Homeowner/Residential, Do I Need a Permit? · Wording matched the official text retrieved 2026-11-06 Official wording All secondary suites require building permits to be legal. check if the property is within a Development Permit Area to determine if your type of construction requires a Development Permit. Contact the Planning and Development Department at 604-927-3430 Accessory buildings, additions, new living space, secondary suites, coach houses.
Bylaw	Zoning Bylaw No. 3000, 1996 (Part 10 and Part 7) and Building Bylaw No. 3598, 2003Zoning Bylaw 3000, Parts 1 and 2 (definitions), s. 101; Building Bylaw No. 3598 (consolidated September 2026), title page · Wording matched the official text retrieved 2026-11-06 Official wording City of Coquitlam Zoning Bylaw No. 3000, 1996 BUILDING BYLAW NO. 3598, 2003

How it works

Coquitlam's Zoning Bylaw 3000 calls a secondary suite, carriage house or garden cottage an "accessory dwelling unit". It counts as a dwelling unit toward the zone's limit per lot, so what you can add depends on your zone.

R-1: up to four dwelling units per lot.
R-2: up to four, or three on lots of 280 m² or less.
R-3: two principal units plus two accessory units.
RS-2: one accessory unit, which must be inside the single-detached house.
R-4 requires at least three units per lot.

In the R zones a detached carriage house or garden cottage is allowed, and a building holding only an accessory unit counts as a principal building. No owner-occupancy rule was found.

Steps

Look up your zone on QtheMap, or call Planning and Development at 604-927-3430. Zones other than RS-2 and R-1 to R-4 were not checked.
Prepare the application form, the Secondary Suite Permit Checklist, proof of ownership and drawings.
Submit through Coquitlam QFile or at the City Hall counter. A Development Permit may also be needed in a Development Permit Area.
Book inspections as work proceeds.

Good to know

Parking (Zoning Bylaw Part 7, small-scale residential): 1 space per dwelling unit under 79 m², 1.5 for 79 to 158 m², 2 over 158 m². In RS-2, A-3 and legacy zones: 1 space per accessory unit. None is required in Transit-Oriented Areas.
The City's older suite FAQ says a suite is only allowed in a single family dwelling, one per dwelling, with one parking space. The current Zoning Bylaw is followed here; confirm with the City.
Suites add a utility surcharge: 40% if authorized, 100% if unauthorized, per the FAQ.

What you'll need

Permit Application Form and the Secondary Suite Permit Checklist
Proof of ownership, or an Agent Authorization Form if you are not the owner
Drawings per the City's secondary suite drawing requirements

Official forms and pages

The same question in other places

Port Coquitlam · Port Moody · Belcarra · Anmore · New Westminster · Burnaby

Secondary suite and carriage house rules in British Columbia, by municipality →

Sources

Secondary Suites FAQs, City of Coquitlam (read 2026-11-05)
Zoning Bylaw 3000, Parts 1 and 2 (definitions) (PDF), City of Coquitlam (read 2026-11-05)
Zoning Bylaw 3000, Part 10 Low Density Residential Zones (PDF), City of Coquitlam (read 2026-11-05)
Zoning Bylaw 3000, Part 7 Off-Street Parking and Loading (PDF), City of Coquitlam (read 2026-11-05)
Information for Building Small-Scale Multi-Unit Housing, City of Coquitlam (read 2026-11-05)
Building & Construction, City of Coquitlam (read 2026-11-05)
Building Projects - Homeowner/Residential, City of Coquitlam (read 2026-11-05)
Building Bylaw No. 3598 (consolidated September 2026), City of Coquitlam (read 2026-11-05)

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