Electric Garage Heaters… The Pros and Cons

If you’re looking for a way to heat your garage or workshop you might want to consider installing an electric garage heater. Generally speaking, electric heaters cost a bit more to operate than gas fired heaters, but there are some excellent benefits to using electric instead. Here are the pros and cons.

Pros:

1. Quiet operation. Electric heaters consist of electric coil heating elements and a prop fan. The coils make no noise as they heat up. A prop fan located behind the coils produces only minimal noise as it pushes air across the warmed up coils and into the garage or shop space. Gas forced air heaters are basically small furnaces, much like a central furnace used in most homes. They are generally louder because they have an open flame that produces noise and vibration as the gas combusts in the heat exchanger. This is especially annoying in attached garages where sound vibrations can resonate through walls and joists into the dwelling space of the home.
2. Easy to install. Electric heaters are fairly easy to install compared to gas heaters because you don’t need to run a gas line or flue. In many homes, getting a gas line to the garage is impractical or unaffordable, so electric makes more sense. However, running electrical power is usually not a do-it-yourself project requiring the services of a licensed electrician. Most vented gas-fired heaters require at least a 4" flue to the outside. Many homeowners fear the job of punching a hole in the roof or an outside wall to eliminate those flue gases. Electric heaters produce no combustion gases, just clean quiet heat, so no flue is required.

Cons:

1. Electricity is generally more expensive than gas in most all of North America. If we compare the cost of heating a typical two-car garage, the electric heater can cost as much as 20% more to operate than a vented forced air gas heater and 40% more than a vent-free infrared gas heater.
2. 240 volt power is required. This is the same power requirement as your oven or electric clothes dryer. You need to ensure that there is enough capacity in your home’s electrical panel to accommodate an additional 40 or 50 amp breaker. A 7.5 kw electric heater at 240V, 1 phase will draw about 31 amps and will require a 40 amp circuit. A 10.0 kw 240V, 1 phase heater will draw about 42 amps, requiring a 50 amp circuit. You’ll want to check the total amp rating of your panel before buying an electric heater.

We’re often asked, "Can’t I just buy a plug-in type electric heater to do the job?"

You can buy such a heater, but it won’t produce nearly enough heat to do the job. A small 110V plug-in electric heater (like one you would buy at Walmart or Home Depot) can only generate about 1.5 kw (1500 watts). That’s equivalent to about 5,119 BTU’s, about 20% of the amount needed to heat a typical two-car garage. At bare minimum, you’ll need at least a 5.0 kw (17,065 BTU) heater, which requires 240V, 1 phase power. The most popular garage heaters are sized at 7.5 kw (25,598 BTU’s) or 10.0 kw (34,130 BTU’s).

What about cost of installation?

That’s a great question and the answer is different for every situation. Normally, a gas heater will cost more to install due to the expense of running a gas line, 110V electrical power and a flue. The additional labor of gas line and flue may make the overall installed cost of the gas heater as much as 35% higher than an electric heater. Therefore, it may take considerable time to pay back that cost difference through whatever energy savings a gas heater may generate compared to an electric heater.

Look at it this way; if you think you’ll be using your heater only occasionally, the ROI (return on investment) of a gas heater generated through energy savings alone may take several years. So, those who only use their heaters occasionally for short stretches of time are excellent candidates for electric heat, whereas those who want to keep their garages warm constantly during the cold months will see much quicker returns with gas.