Secondary suites

• Floor area* of the suite must be no larger than 33 percent of the combined floor area of the principal dwelling and the secondary suite, or 74 m2 (800 sq. ft), whichever is less.
• Floor area of the secondary suite cannot be less than 32.5 m2 (350 sq. ft).
• Only one entrance to the building may be located on the façade that faces the street, unless the dwelling contained another street-facing entrance before the creation of the secondary suite.
• Secondary suites cannot be used as home-based businesses, care homes, or neighbourhood rehabilitation facilities.
• Properties with secondary suites must provide a minimum of two off-street parking spaces.
• Attached secondary suites may be permitted in all zoning districts that allow single family dwellings. These include zoning districts: A, RR5, RR2, R1, R2, RMF, RMU, and C1.

*Based on the requirements of the City of Winnipeg Zoning By-law 200/2006 which is more restrictive than the Manitoba Building Code. If you are proposing a suite larger than zoning allows, you will need to apply for a conditional use application and provide sound rationale for the increased size.

• Development permit
• Building permit
• Separate electrical & plumbing permits
• The property must be a minimum of 325 m² (3,500 sq. ft).
• The secondary suite must be located within the rear yard behind the principal building.
• No windows except for clerestory windows (a row of windows above eye-level), balconies or entrances are permitted facing the interior side lot line where the interior side yard setback is 2.4m (8’) or less.
• All habitable areas must be located above grade.
• Plans showing the location and design of the secondary suite, including building elevations, floor plans, materials, exterior lighting, windows, doors, balconies, patios, outdoor spaces, fencing, landscaping and parking areas must be submitted before or in conjunction with an application for a development permit, and approved by the Director before issuance of the development permit.
• Floor area of the suite must be no smaller than 32.5 m² (350 sq. ft) and no larger than 55.7 m² (600 sq. ft).
• The height of the secondary suite is limited to 4.57 m (15’-0”) if it is situated on grade and 7.62 m (25’-0”) if it is situated above a detached garage.
• It can be no closer than 3.05 m (10’-0”) from the primary dwelling.
• Minimum rear yard setback is 7.6 m(25’) if there is no rear lane.
• Minimum rear yard setback is 1.5m (5’) if there is a lane where no entrance, balcony or window may face the rear lot line.
• It must be no greater than 45.7 m (150’-0”) from the nearest curb on the front street and an unobstructed pathway. A minimum of 762 mm (2’-6”) in width must be provided between the front property line and the secondary suite.
• No roof decks are allowed above the floor area.
• The maximum lot coverage of the property shall be no greater than the applicable zoning district allows.
• The maximum lot coverage for all accessory structures on the property shall be no greater than 44.9 m2 (484 sq. ft) or 12.5% of the total lot area, to a maximum of 81.75 m2 (880 sq. ft).
• It cannot be used as home-based business, care home or neighbourhood rehabilitation facility.
• Properties with detached secondary suites must provide a minimum of two off-street parking spaces. A secondary suite may not be subdivided from the principal building.
• Detached secondary suites are only permitted in R1 and R2 zoning districts with single-family dwellings.

• If X = 900 to 1,200 mm then T = 100 mm
• If X = 1,500 to 1,800 mm then T = 75 mm
• If X = 2,100 or more then T = 50 mm

Diagram of insulation detail for pipe in excavation project noting the differences in millimeters when the depth (variable X) has different values. Sand should surround the pipe, followed by rigid polystyrene insulation.

A dwelling unit with a secondary suite must have at least one exit which leads directly outside. Subsection 9.9.9. of the Manitoba Building Code deals with the egress from dwelling units. Required entrance doors shall have a minimum width of 810 mm (2'-8"). An exit stairway shall have a minimum width of 860 mm (2'-10").

Separations from unit to unit are required to be a smoke-tight barrier. Common walls are required to have a minimum ½ in. drywall on either side, taped and sanded and sealed at junctions and penetrations. Floors must have a minimum ½ in. drywall on the bottom finish, taped and sanded, and a floor covering on top. Doors in smoke-tight barriers must be a minimum 1¾ in. thick solid core wood door with an approved self-closing device.

Where the suite does not contain a sprinkler, each bedroom shall have at least one window designed as a means of egress, should the required exit become obstructed. An egress window must have an unobstructed opening of 0.35 m² (3.8 ft²) and the minimum height or width of the opening shall be not less than 380 mm (1'-3"). Egress windows are to have either a casement or sliding operation. Where a window well serves an egress,  a clearance of at least 760 mm (2'-6") must be provided in front of the window.

The Manitoba Building Code requires a minimum 1.95 m (6'-5") floor-to-ceiling height for a secondary suite. Clear heights under beams can be reduced to 1.85 m (6'-1"), but door openings cannot be reduced to less than 1.89 m (6'-2 1/2") where a lower ceiling height does not allow for a full height door.

A means of protection against the spread of smoke and fire from one dwelling unit to another is essential. Also, any common space, other ancillary spaces, or rooms containing heating equipment must be protected from the rest of the building. This is achieved by providing a layer of 1/2" drywall on the underside of floor framing (ceiling) and on both sides of wall studs that separate the dwelling unit from the suite or common spaces.

Alarms must be installed in the primary and secondary units and in ancillary/common spaces not within the dwelling units. Alarms must be interconnected so that the activation of one alarm causes all alarms within both dwelling units to sound. Where a dwelling contains a fuel burning appliance (gas furnace, fireplace, wood stove, gas hot water tank, gas appliance, etc.) or has an attached garage, a carbon monoxide alarm must be installed so that each bedroom is protected by a carbon monoxide alarm, and in each room that contains a solid fuel burning appliance. Installers should refer to the manufacturer’s installation guidelines.

The Sound Transmission Classification (STC) between units is required to be rated at a minimum of 43. Common walls and ceilings are required to have min. 1/2" drywall, resilient sound channels and batt insulation. Or, any wall/ceiling assembly that meets STC of 43 (as prescribed by the code) is also acceptable.

A secondary suite requires a dedicated heating system with controls, separate from the system serving the primary dwelling unit in the house. Air duct distribution systems cannot be interconnected between dwelling units. Where a separate forced air heating system is provided, a heat recovery system must be installed to provide for the exhaust of stale air from, and supply of fresh air into the suite. When no forced air heating system exists, incoming fresh air shall be supplied through a system of supply ducts to each bedroom, each story in the dwelling unit without a bedroom, and to the principal living area.

Water shut off valves are required for the principle dwelling and the secondary suite. These can be located in each suite, or in a common mechanical room.

Occupants of both the primary dwelling unit and the secondary suite must have ready access to all circuit breakers that serve their dwelling unit. This can be achieved by a single electrical service with the panelboard located in a common space, or a dedicated electrical service for each dwelling, with a panelboard located in each dwelling unit.