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Trail secondary suite and carriage house rules

Can I add a secondary suite or a carriage house?

Trail, British ColumbiaChecked against official textSources read 2026-11-06

Short answer

Yes. In the City of Trail's R1 and R3 residential zones a secondary suite (inside the home) and an accessory suite (such as a carriage house or garage suite) are permitted uses. Secondary suites are also allowed in some other zones. A building permit is required.

Key facts

Secondary suite allowedYes. A secondary suite is a permitted use in R1 and R3, and also in R4 (townhome buildings), R6 (row houses and town houses), C2 (single and two family dwellings), C6 (single family dwellings) and A1 (single family dwellings). It must be in a single detached, semi-detached or townhouse dwelling, not a duplex.City of Trail Zoning Bylaw No. 2503, 2002, ss. 6(1)(g), 7(1)(i); City of Trail Zoning Bylaw No. 2503, 2002, ss. 8(1)(h), 9(1)(h), 14(1)(t), 18(1)(q), 28(1)(i); City of Trail Zoning Bylaw No. 2503, 2002, s. 3(17)(a)(i) · Wording matched the official text retrieved 2026-11-06
Official wording
(g) secondary suites; (h) accessory suites;
(i) secondary suites;
It may accommodate a secondary suite in a semi-attached dwelling, but not in a duplex dwelling.
secondary suite, in three family and four family dwelling townhome buildings;
secondary suite, in row houses and town houses;
secondary suite, in single and two family dwellings;
secondary suite, in single family dwellngs;
secondary suite, in single family dwellings;
A secondary suite shall only be permitted within a single detached, two unit or townhouse dwelling.
Coach house or garden suite allowedYes. An accessory suite (garden suite, laneway home, carriage house or garage suite) is a permitted use in the R1 and R3 zones, only with a single detached, two-unit or townhouse dwelling. It must be at least 3 m from the principal building.City of Trail Zoning Bylaw No. 2503, 2002, s. 1(2) definition; City of Trail Zoning Bylaw No. 2503, 2002, ss. 6(1)(h), 7(1)(j), 3(18)(a)(i), (xii) · Wording matched the official text retrieved 2026-11-06
Official wording
means a self-contained accessory dwelling unit, such as a garden suite,
laneway home, carriage house or garage suite, located on the same legal lot as an associated
(g) secondary suites; (h) accessory suites;
(j) accessory suites;
An accessory suite shall only be permitted with a single detached, two unit or
An accessory suite must be located a minimum of 3 m from the principal building.
LimitsSecondary suite: at most 50% of the principal building's total floor area, a separate exterior entrance, full fire separation, shared utility connections, no strata subdivision, and no bed and breakfast in the same building. Accessory suite: floor area no more than the principal dwelling unit's. Lots 280 m² or smaller: up to 3 accessory dwelling units; larger lots: the greater of 4 or 1 per principal dwelling unit.City of Trail Zoning Bylaw No. 2503, 2002, s. 3(17)(a)(iv)-(xiii); City of Trail Zoning Bylaw No. 2503, 2002, s. 3(18)(a)(v), Table 1 · Wording matched the official text retrieved 2026-11-06
Official wording
The maximum floor area of a secondary suite shall not exceed 50% of the total floor area of the principal building.
A secondary suite must have an entrance from the exterior of a building which is separate from the main entrance of the principal use.
Secondary suites must share common utility connections with the principal building.
A secondary suite cannot be strata subdivided from the principal dwelling
A secondary suite shall not be permitted in the same building that has a bed and
The maximum floor area of an accessory suite must not exceed the floor area of the associated principal dwelling unit.
Table 1: Maximum Accessory Dwelling Units Permitted on a Lot
Up to 280 m 3 units
Greater of 4 units or 1 per principal dwelling unit
ParkingParking Table 2: for accessory dwelling units, 1 parking space where there are 2 or fewer units, and 0.5 per unit for each additional unit.City of Trail Zoning Bylaw No. 2503, 2002, Part VII, Table 2; City of Trail Zoning Bylaw No. 2503, 2002, s. 3(17)(a)(viii) · Wording matched the official text retrieved 2026-11-06
Official wording
Accessory dwelling unit
2 or fewer units: 1 parking
space; For each additional
unit, 0.5 per unit
Off-street parking shall be in conformance with the regulations in Part VII of this
PermitsA building permit is required to establish a secondary suite or an accessory suite, and the suite must meet the BC Building Code. A development permit is also needed if the lot is in a development permit area designated in the Official Community Plan.City of Trail Zoning Bylaw No. 2503, 2002, ss. 3(17)(a)(x), 3(18)(a)(viii); City of Trail Zoning Bylaw No. 2503, 2002, s. 4(2) · Wording matched the official text retrieved 2026-11-06
Official wording
The establishment of a secondary suite requires a building permit.
The establishment of an accessory suite requires a building permit.
All owners of land within the development permit areas designated in the City of Trail Official
BylawCity of Trail Zoning Bylaw No. 2503, 2002 (ss. 3(17), 3(18), Table 1); City of Trail Building Bylaw No. 2548, 2003City of Trail Zoning Bylaw No. 2503, 2002, Title page; City of Trail Building Bylaw No. 2548, 2003, Title page · Wording matched the official text retrieved 2026-11-06
Official wording
ZONING BYLAW NO. 2503, 2002
BUILDING BYLAW NO. 2548, 2003

How it works

Under the City of Trail's Zoning Bylaw, a secondary suite is a permitted use in R1 and R3, and also in R4 (townhome buildings), R6 (row houses and town houses), C2 (single and two family dwellings), C6 (single family dwellings) and A1 (single family dwellings). It must be in a single detached, semi-detached or townhouse dwelling, not a duplex.

An accessory suite (garden suite, laneway home, carriage house or garage suite) is permitted only in R1 and R3, with a single detached, two-unit or townhouse dwelling. It must be at least 3 m from the principal building.

Steps

  1. Confirm your zone (see zoning-lookup).
  2. Check the rules below against your plans with Development Services (Planning@Trail.ca).
  3. Apply for a building permit. The suite must meet the BC Building Code.
  4. If your lot is in a development permit area in the Official Community Plan, a development permit is also needed.

Good to know

  • Secondary suite: at most 50% of the principal building's total floor area, a separate exterior entrance, full fire separation, shared utility connections, no strata subdivision, and no bed and breakfast in the same building.
  • Accessory suite: floor area no more than the principal dwelling unit's. Lots of 280 m2 or smaller may have up to 3 accessory dwelling units; larger lots, the greater of 4 or 1 per principal dwelling unit.
  • Height: an accessory building with a suite may be 2 storeys (10 m) with the suite on one storey; a stand-alone suite building may be 1 storey (6.5 m).
  • Parking: 1 space for accessory dwelling units where there are 2 or fewer units, and 0.5 per unit for each additional unit. The table does not say whether the main dwelling counts as a unit.
  • We found no owner-occupancy requirement in the suite rules.

Official forms and pages

The same question in other places

Warfield · Rossland · Montrose · Fruitvale · Castlegar · Salmo

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

Sources

  1. City of Trail Zoning Bylaw No. 2503, 2002 (PDF) (read 2026-11-06)
  2. Building Permits, City of Trail (read 2026-11-06)
  3. City of Trail Building Bylaw No. 2548, 2003 (PDF) (read 2026-11-06)

Checked by script, not yet by a person: the official wording behind 6 of 6 facts was matched to the official text. How answers are checked.