Secondary suites in Burnaby: the rules for building one into a new home

What the BC code counts as a secondary suite

The BC Building Code 2024 (Division A, Article 1.4.1.2.) defines a secondary suite as a self-contained dwelling unit in a building that holds only one other dwelling unit and common spaces, where both units are one real estate entity. Both homes sit in one house, on one title.

The code's note to that definition lists common laundry facilities and common service rooms as allowed shared spaces. So both homes can share one laundry room and one mechanical room, as long as those rooms meet the fire rules further down this page.

A suite in its own building at the back of the lot is a different kind of unit. Our laneway and coach house guide covers those rules.

Where Burnaby allows suites, and how they count

The City's secondary suite program page lists the zones where suites are allowed: R1, A1, A2, A3 and RM6. It covers single-family homes, duplexes, multiplexes and rowhouses in those zones.

Since July 1, 2024, the R1 zone allows three or four units on a lot, and up to six near frequent transit. The City's announcement says secondary suites count toward the total number of units allowed on the lot. A house with a suite therefore uses two of those units. Our Burnaby R1 zoning guide explains the unit counts lot by lot.

The program page also lists what an owner has to do:

• Get the building and subtrade permits.
• Meet the BC Building Code and pass every inspection.
• File a supplementary utility fee declaration if the suite is rented.
• Hold a business licence if you rent the suite and do not live on the property.

If you are choosing between a house with a suite and a duplex, our post on duplex vs house with a suite compares the two.

A new home meets the full code; a conversion gets some relief

Sentence 1.1.1.1.(6) of the BC Building Code gives a table of alternate rules for adding a suite to an existing building. The code says those rules do not apply to new additions or new buildings. A new custom home with a suite is built to the standard rules.

Ceiling height shows the difference:

Sources: BC Building Code 2024, Division B Table 9.5.3.1. and Division A Table 1.1.1.1.(6).

On a new build we set the basement height on the first section drawing, so the suite gets full-height rooms and the ducts and beams run where they do not cut into them.

Fire and sound between the two homes

Article 9.10.9.16. requires the suite and the main home to be separated from each other, and from any shared rooms, by a fire separation: a wall or ceiling built to hold back a fire for a set number of minutes. The rating depends on the smoke alarms:

• 15 minutes if all smoke alarms are photo-electric and interconnected.
• 30 minutes if extra interconnected photo-electric alarms are added.
• 45 minutes in other cases.
• No rating if the house has sprinklers.

Article 9.11.1.1. adds a sound rule for the same walls and ceilings. It gives three ways to meet it: sound-absorbing material in the joists and studs with thin metal strips holding the drywall away from the framing on one side (called resilient channel) and 12.7 mm drywall; a lab sound rating of 43 or more (called STC); or a tested result of 40 or more for the whole built assembly (called ASTC).

Every pipe, duct and wire that crosses the fire separation has to be sealed so the rating still holds. Our acoustic design post covers how we go past the sound minimum when the suite is for family.

Bedroom windows and exits

Article 9.9.10.1. applies to every bedroom in the suite unless the suite has sprinklers. Each bedroom needs at least one outside window or door that opens from the inside without keys, tools or special knowledge. The window must:

• Give a clear opening of at least 0.35 square metres.
• Have no side of that opening shorter than 380 millimetres.
• Stay open on its own during an emergency.
• Have at least 760 millimetres of clear space in front of it if it opens into a window well, with any cover over the well openable from the inside.

Exits have their own rules. Under Article 9.9.9.3., when the suite door opens onto a stair or hallway that both homes share and that has only one exit, the code can require a second way out. The house avoids that requirement when it has sprinklers, or when each storey of each home has direct access to a balcony or to an openable window at least 1 metre high and 0.55 metres wide, with its sill no more than 1 metre above the floor and 7 metres above the ground.

A suite whose door opens straight outside at ground level does not use a shared stair or hallway, so this rule does not apply. That door is the first thing we place on a suite plan, and our post on designing a suite into a Burnaby custom home explains why.

Plumbing, hot water and meters

Section 9.31 of the BC Building Code gives every dwelling unit a kitchen sink, a washbasin, a bathtub or shower, a toilet and a supply of hot water. A suite gets all of them inside the suite.

Article 2.6.1.3. of the National Plumbing Code 2020, which BC uses as its plumbing code, requires a shut-off valve where the water supply enters each dwelling unit in a residential building with more than one. A fuel-fired water heater that serves both homes can sit in a service room whose fire rating at least matches the rating between the units (BC Building Code Article 9.10.10.4.).

The province's Home Suite Home guide adds that suite occupants should be able to reach their hot water tank and its controls without relying on the people in the other home. Our secondary suite plumbing post goes through the pipes, valves and water heater choices in detail.

How we plan a suite into a new Burnaby custom home

Every rule above is simple to meet on a drawing and hard to change once the walls are closed. We settle the suite on the first floor plan, in this order:

1. Check the zone and the unit count. Confirm the lot is in a zone that allows a suite and how many units remain on an R1 lot.
2. Place the suite's outside door. A direct exit for the suite keeps the shared-exit rules out of the plan.
3. Set the basement height. Full 2.1 m rooms, with beams and ducts routed outside the suite's rooms.
4. Size the bedroom windows and wells. 0.35 square metres of opening and 760 millimetres in front of each window in a well.
5. Choose the smoke alarm and sprinkler approach. That choice sets the fire rating of the ceiling between the homes.
6. Stack the wet rooms. The suite kitchen and bathroom go under the main floor's, so one drain stack serves both homes.
7. Decide on meters and water heaters. Shared or separate, based on who will live in the suite.

A suite drawn on the first plan fits the house as built. A suite added after the framing is done means moving doors, windows and pipes.Icon Projects Team

Questions owners ask

Can I build a secondary suite in my Burnaby house?

The City of Burnaby allows secondary suites in single-family homes, duplexes, multiplexes and rowhouses in the R1, A1, A2, A3 and RM6 zones. You need building and subtrade permits, and the suite must pass its inspections. The BC Building Code does not allow a suite in a duplex where one unit sits on top of the other.

Does a secondary suite count toward the number of units on a Burnaby R1 lot?

Yes. Since July 1, 2024, Burnaby's R1 zone allows three or four units on a lot, and up to six near frequent transit. The City says secondary suites count toward the total number of units allowed on the lot.

What ceiling height does a secondary suite need in a new house?

A new house must meet the BC Building Code's standard table: 2.1 metres in living rooms, dining rooms, kitchens and bedrooms, over a set minimum area of each room. The code allows 1.95 metres only when a suite is added to an existing building, and that relief does not apply to new homes or new additions.

What fire separation is required between a suite and the main home?

The BC Building Code ties the rating to the smoke alarms. It is 15 minutes when all smoke alarms are photo-electric and interconnected, 30 minutes when extra interconnected photo-electric alarms are added, and 45 minutes otherwise. A house with sprinklers needs no fire-resistance rating between the two units.

What size does a bedroom window in a basement suite have to be?

Unless the suite has sprinklers, each bedroom needs a window or outside door that opens from the inside without keys or tools. The window opening must be at least 0.35 square metres, with no side shorter than 380 millimetres. If it opens into a window well, the well needs at least 760 millimetres of clear space in front of the window.

Does a secondary suite need its own water meter, hydro meter or gas meter in Burnaby?

Burnaby requires one water meter for the property on every new single family or two-family home, with or without a suite. BC Hydro's tariff leaves a suite on a single legal title out of its one-meter-per-dwelling rule, so a second electric meter is the owner's choice. FortisBC offers a second gas meter so each home can run its own heating and hot water.

Does a secondary suite need its own water shut-off valve?

The National Plumbing Code 2020, which BC uses as its plumbing code, requires a shut-off valve where the water supply enters each dwelling unit in a residential building with more than one. The BC Building Code defines a secondary suite as a dwelling unit. We place the suite's valve where its supply line enters the suite and confirm the layout with Burnaby's plumbing inspector.

Is there a fee for a rented secondary suite in Burnaby?

Yes. When a suite is rented, the City adds a supplementary water and sewer charge to the property's utility notice, and the owner files a declaration with the City. An owner who rents a suite without living on the property also needs a business licence, according to the City's secondary suite program page.