What are the NB code requirements for a garage with a propane heater installation?

A propane-fired garage heater in New Brunswick requires compliance with several overlapping codes and standards — the NB Building Code, the NB Gas Distribution Act, CSA B149.1 (Natural Gas and Propane Installation Code), and your local municipality's requirements. Getting this right matters both for safety and for passing inspection.

Propane Heater Installation Requirements for NB Garages

Permits and Licensed Trades

Every propane heater installation in New Brunswick requires two separate permits: a building permit (if the heater installation is part of a new garage or a significant renovation) and a gas permit issued under the NB Gas Distribution Act. The gas work itself — running the propane line, connecting the heater, and pressure-testing the system — must be performed by a licensed gas fitter registered in New Brunswick. This is not a DIY task under any circumstances. The NB Technical and Safety Services Commission oversees gas installations, and unpermitted propane work is both illegal and a serious fire and explosion hazard.

Your propane supplier will also want to inspect the installation before filling or connecting a tank, and most suppliers won't connect service to a system that hasn't been inspected and approved.

Clearances and Heater Placement

CSA B149.1 governs propane appliance installation and sets minimum clearances that your gas fitter will follow. For a typical propane unit heater (the ceiling-hung forced-air type common in NB garages), you need a minimum clearance of 18 inches from combustibles on all sides unless the heater is listed for a reduced clearance. The heater must be mounted high enough that the burner and ignition components are at least 18 inches above the floor level — this is critical in garages because propane is heavier than air and will pool at floor level if there's a leak. A spark at floor level in a propane-rich environment is catastrophic.

The heater must not be installed directly above the vehicle parking area where fuel vapours could accumulate. Positioning it toward the front wall or a side wall, directed to circulate air without blowing directly onto vehicles, is the typical approach in NB garages.

Ventilation Requirements

This is where many homeowners are surprised. A propane heater requires combustion air — the heater needs a fresh air supply to burn safely and efficiently. In a tightly insulated NB garage, a sealed building envelope can starve the heater of combustion air, leading to incomplete combustion, carbon monoxide production, and sooting of the heat exchanger.

CSA B149.1 requires that the garage have adequate combustion air openings, typically calculated at 1 square inch of free opening per 1,000 BTU/hr of appliance input. For a common 30,000 BTU garage heater, that's 30 square inches of combustion air opening — roughly a 6x5-inch vent. Your gas fitter will calculate this based on the heater's input rating and the garage's volume and tightness.

Direct-vent (sealed combustion) propane heaters draw combustion air from outside through a dedicated pipe and exhaust through a coaxial vent — these are an excellent choice for insulated NB garages because they eliminate the combustion air problem entirely and are more efficient. They cost slightly more but are increasingly the preferred option for well-insulated garages.

Regardless of heater type, every heated garage in NB should have a through-wall exhaust fan for general ventilation, and a carbon monoxide detector is essential — it's not required by code in detached garages in all municipalities, but it should be treated as mandatory given the risk.

Propane Tank Placement

The propane tank itself has setback requirements under CSA B149.1. A 100-pound (420 lb) or smaller tank must be at least 3 feet from any building opening (windows, doors, vents) and 5 feet from any ignition source. Larger tanks (100 gallons and up, common for whole-garage heating) require 10 feet from building openings and must be on a stable, level pad. Tanks cannot be installed inside the garage — they must be outside, accessible for delivery, and protected from vehicle damage if near a driveway.

Attached vs. Detached Garage Considerations

If your garage is attached to the house, the propane heater installation becomes more complex. The fire separation wall between the garage and the house must remain intact — any penetrations for gas lines or venting must be properly fire-stopped with approved sealants. The heater's flue or vent must not terminate near windows, doors, or the soffit of the house in a way that could allow exhaust gases to enter the living space. Your gas fitter and building inspector will review the venting termination location carefully.

In an attached garage, a carbon monoxide detector on the house side of the fire separation wall is strongly recommended and may be required by your municipality.

Practical Tips

A 30,000 to 60,000 BTU propane unit heater is appropriate for most two-car NB garages (24x24). Sizing too large leads to short-cycling and wasted propane; sizing too small means the heater runs constantly on the coldest days. Your gas fitter can do a proper heat loss calculation based on your garage's insulation levels, ceiling height, and local design temperature — for most of NB, the design temperature is -25°C to -29°C depending on location.

Budget $1,500-$3,500 installed for a propane unit heater including the heater, gas line, venting, and labour. The propane tank itself (if you don't already have one) adds $500-$1,500 depending on size and whether you rent or purchase.

For finding licensed gas fitters and garage contractors in your area, browse the New Brunswick Construction Network directory at newbrunswickconstructionnetwork.com — or let New Brunswick Garages match you with a local contractor who can coordinate the full installation.