What type of heater is most energy-efficient for a New Brunswick garage?

The most energy-efficient heater for a New Brunswick garage depends on how you use the space, but for most NB homeowners, a natural gas or propane unit heater offers the best balance of efficiency, operating cost, and practical performance in our Maritime climate. If your garage is well-insulated and you have access to natural gas service, a modern condensing unit heater with an efficiency rating of 90-95% is the top choice for regular use.

Before discussing heater types, the single most important factor in garage heating efficiency is insulation. No heater, regardless of how efficient it is, will perform well in an uninsulated or poorly insulated garage. New Brunswick's winter temperatures regularly reach -20 to -30 degrees Celsius, and an uninsulated two-car garage loses heat so rapidly that even a large heater runs continuously without maintaining a comfortable temperature. Before investing in any heating system, ensure your garage has at least R-20 wall insulation, R-40 to R-50 ceiling insulation, and an insulated garage door rated to R-16 or higher. A well-insulated two-car garage can be kept comfortable with a heater half the size needed for an uninsulated space.

Natural gas unit heaters are the most popular choice for NB garages where natural gas service is available (Moncton, Saint John, Fredericton, and surrounding communities). A 45,000-75,000 BTU gas-fired unit heater costs $1,500 to $3,500 installed including the gas line connection, and modern units operate at 80-95% efficiency. Monthly operating costs during NB's six-month heating season run approximately $80 to $200 per month for a well-insulated two-car garage, depending on your thermostat setting and how often the garage door is opened. The key advantage of gas unit heaters is their ability to recover quickly — when you open the garage door on a -25 degree day and the temperature plummets, a gas heater brings the space back to working temperature within 15-20 minutes.

Propane unit heaters are essentially the same equipment as natural gas units but run on propane, making them the go-to choice for rural NB properties without natural gas service. Efficiency ratings are comparable (80-95%), but operating costs are approximately 30-50% higher than natural gas because propane costs more per BTU in New Brunswick. A 250-gallon propane tank and annual fuel costs of $1,200 to $2,500 are typical for regular winter use of a two-car garage workshop.

Electric heaters come in several varieties. 240V electric forced-air heaters (4,000-7,500 watts) are inexpensive to purchase and install at $300 to $800 installed, but NB's electricity rates make them the most expensive option to operate — roughly $200 to $400 per month for a well-insulated two-car garage kept at workshop temperatures. Electric infrared/radiant heaters are a more targeted option that heats objects and people directly rather than heating the air. They are excellent for garages where you work in one area because they provide immediate warmth without needing to heat the entire volume of air. Operating costs are lower than forced-air electric because you are only heating a zone rather than the whole space.

Ductless mini-split heat pumps are the emerging efficiency champion for NB garages. Modern cold-climate mini-splits operate effectively down to -25 to -30 degrees Celsius and deliver 2-3 times more heat energy than the electrical energy they consume, making them the lowest-cost option to operate. A 12,000-18,000 BTU mini-split costs $3,000 to $5,500 installed and can both heat and cool the garage. Monthly heating costs run $50 to $120 for a well-insulated two-car garage. The main drawback is slower recovery time compared to a gas heater — if you open the garage door frequently in winter, a mini-split struggles to keep up.

In-floor radiant heating (hydronic) is the premium option at $8 to $14 per square foot installed and must be planned before the concrete slab is poured. It provides the most comfortable, uniform heat and is ideal for garages used as serious workshops. However, the high installation cost means it is typically only justified for garages that will be used daily throughout winter.

For most NB homeowners, the practical recommendation is a natural gas unit heater if you have gas service, or a cold-climate mini-split heat pump if you want the lowest operating costs. Either way, invest in proper insulation first — it is the foundation of an energy-efficient heated garage. Find qualified HVAC and garage contractors through the New Brunswick Construction Network at newbrunswickconstructionnetwork.com.