We all know what is the best way to heat a garage: just use an electric garage heater. Which one through? There are 1000s of 120V and 240V electric heaters for garages or shops and it’s quite a mundane task to check all of them. That’s why we narrowed down the choices to 4 best 120V electric garage heaters and the 5 best 240V electric garage heaters (found in two spec-by-spec comparison tables below).
To choose the best electric garage heater on your 1st pick, we will need to figure out the following specs:
- What size garage heater do you need? To adequately heat up a garage, you will need about 30 BTU (or 8.8W) per square foot. Here is where the 120V vs 240V heater dilemma comes in: All 120V can produce up to 1500W (or 5,118 BTU). That’s enough to heat up a 170 sq ft garage (small 1-car garage). However, if you want to heat up a 2-car, 3-car, 4-car, or even 5-car garage, you should go for a 240V electric heaters that can produce up to 10 times as much heating output as 120V units (up to 15,000W or 51,180 BTU) enough for up to 1,700 sq ft garages.
- Energy efficiency (inclusion of an external thermostat). If a garage heater operates at 100% output all the time, it will impact your electricity bill quite a lot. That’s why the best electric garage heaters include an external thermostat (different from the internal thermostat, we’ll explain that later on). The thermostat will reduce the heating output and thereby electricity expenditure to only produce as much heat as needed. This can reduce the cost of running an electric garage heater by up to 80%.
- Wiring and positioning. Most of the bigger 240V electric heaters will be hard-wired and ceiling-mounted. You also need to consider wiring to handle all the amps; a 5000W 240V heater will draw 21 amps. That means you will need a 12 AWG wire and 30A breakers. Smaller 120V 1500W heaters can be plugged into a standard outlet (they draw about 12.5 amps and require only standard 14 AWG copper wires).
- Electric heater should be reliable and safe to use. You have good and bad electric garage heaters. The best way to choose one that will last for a long is to go with reputable brands like King Electric, Stiebel Eltron, Fahrenheit, Comfort Zone, Dyan-Glo, and so on.
Here’s the deal right off the batt:
120V 1500W electric heaters are the easiest ones to use. However, they produce just a little over 5,000 BTU of heating output and that will usually not be enough to adequately heat (to let’s say 70°F) a bigger 1-car, 2-car, 3-car, 4-car garage, and so on. For that, you will need a bigger 5000W, 10.000W, or even 15.000W 240V garage heater.
In short, you can have two strategies here:
- Get one or more 120V 1500W heaters. You will usually have to use 2 or more 120V heaters to properly heat a garage. However, you can just start with 1 heater and then another 120V 1500W heater if needed.
- Just get an adequately sized 240V garage heater. Yes, you may need to upgrade your electric circuit a bit, but you will have just one heater that is powerful enough to heat a garage on its own.
That’s why you will find two tables further on. The 1st one includes a selection of the best 120V garage electric heaters and the 2nd one includes a selection of the best 240V electric garage heaters.
First, however, it makes sense to go over sizing, thermostats, amp draws, and so on to get a handle on what is the right way of choosing the best electric heater for your garage.
Let’s start with how many watts heater you need for your garage:
What Size Electric Heater Do I Need For A 1-Car, 2-Car, 3-Car, And 4-Car Garage?
Every selection of an electric heater for a garage starts with wattage. Because electricity is converted to heating output with nearly 100% efficiency (about 98%, to be exact), wattage is equal to BTU output.
For heating a garage, you will need quite a lot of heating output. A simple rule of thumb you can follow is ’30 BTU per sq ft’ of the garage. Garages are usually detached and have inferior insulation to a house.
Home Inspection Insider provides us with a good estimate of the size of multicar garages. Based on this and using the 30 BTU rule of thumb, we have prepared this table with the electric heater sizes for different-sized garages:
|Garage Size:||Width (Ft):||Length (Ft):||Square Footage:||BTU Output:||Heater Wattage:|
|1-Car Garage||12 – 16 ft||20 – 24 ft||240 – 384 sq ft||7,200 – 11,520 BTU||2110 – 3380 Watts|
|2-Car Garage||18 – 22 ft||20 – 22 ft||440 – 624 sq ft||13,200 – 18,720 BTU||3870 – 5480 Watts|
|3-Car Garage||32 – 40 ft||20 – 30 ft||620 – 816 sq ft||18,600 – 24,480 BTU||5450 – 7170 Watts|
|4-Car Garage||40 – 44 ft||20 – 24 ft||800 – 1056 sq ft||24,000 – 31,680 BTU||7030 – 9280 Watts|
Here is how to read this table:
Let’s say you need an electric heater for a 2-car garage. These garages have an 18 – 22 ft width and 20 – 22 ft length, with total square footage ranging from 440 to 624 sq ft. When you multiply the square footage by 30 BTU per sq ft, you see that you need anywhere from 13,200 BTU to 18,720 BTU heating output. When you convert BTUs to watts, you see that you would need anywhere from 3870 to 5480 watt electric heater.
You can go with:
- A 5000W 240V electric heater. This is the most common size electric heater for a 2-car garage.
- Three 1500W 120V electric heaters. The combined wattage is 4500 watts which is about enough to adequately heat a 2-car garage.
If you know the square footage of your garage, you can simply calculate the size of the electric heater you need using this formula:
Electric Heater Wattage = Garage Square Footage × 30 BTU/Sq Ft × 0.293 Watts/BTU
30 BTU per sq ft is the rule of thumb for garage heater sizing and 0.293 Watts/BTU converts BTUs to watts.
Example of how to use this formula: Let’s say you need an electric heater for a 500 sq ft garage. How many watts heater should you get? Just insert the 500 sq ft into the formula like this;
Electric Heater Wattage (500 Sq Ft) = 500 Sq Ft × 30 BTU/Sq Ft × 0.293 Watts/BTU = 4395 Watts
For a 500 sq ft garage, you will need a 4395 watt heater. You can go with a 5000W 240W heater here or opt for 3 1500W 120V heaters.
A good estimate is offered by King Electric as well for their versatile 240V electric heaters for the garage (check #1 King Electric ECO heaters in the 2nd table):
How To Know Which Electric Heater Is Energy Efficient? (External Thermostat)
As stated before, all electric heaters convert almost 100% of electricity to heating output. A 1500W 120V heater will produce 5118 BTU of heating output when running at 100% output.
Here are the costs of running an electric heater per hour when operating at 100% output and at the US national average electricity cost of $0.1319/kWh:
- 1500W heater will consume 1.5 kWh of electricity per hour. That means it will cost about $0.20 per hour to run a 1500W heater at 100% output.
- 5000W heater will consume 5 kWh of electricity per hour. That means it will cost about $0.66 per hour to run a 1500W heater at 100% output.
- 7500W heater will consume 7.5 kWh of electricity per hour. That means it will cost about $0.99 per hour to run a 1500W heater at 100% output.
- 10,000W heater will consume 10 kWh of electricity per hour. That means it will cost about $1.32 per hour to run a 1500W heater at 100% output.
- 15,000W heater will consume 15 kWh of electricity per hour. That means it will cost about $1.98 per hour to run a 1500W heater at 100% output.
Obviously, you want to reduce the running cost of an electric heater as much as possible. This means you have to get a heater that is energy efficient but what does energy efficiency even mean if electricity is directly converted to heat at 100% efficiency?
Well, there are two kinds of heaters:
- Electric heater without an external thermostat. If you have a 1500W 120V heater and set it to 1500W, it will always produce 1500 watts or 5118 BTU of heating output (100%), even if your garage is already at 80°F.
- Electric heater with an external thermostat. This heater will run at 100% only when it is below the thermostat set temperature (let’s say 72°F). When it hits 72°F, however, it will no longer produce 100% of its capacity. A 1500W heater will reduce the heating output to 1000W, 500W, or even stop heating. The point here is to sustain the acceptable garage temperature. In such a way, you will not run the electric heater at 100% output, but at a lower 20% – 90% output. This will reduce the costs of running a garage electric heater.
In short, if you want an energy-efficient heater, you need to get one with an external thermostat. You can set the temperature on the heater itself or via a remote control.
Note: ‘External’ thermostat is a very important word here. All electric heaters have an internal thermostat that prevents the heater from going up in flames. It’s just a safety measure to prevent overheating; it has nothing to do with energy efficiency. That’s why check that the electric heater you are looking at has an external thermostat where you can set the garage temperature.
Where To Place And How To Wire A Garage Heater?
When choosing a 120V or 240V electric garage heater, you will see that you have 3 kinds of heaters depending on where to place them. These 3 locations are:
- Ceiling-mounted. Almost all 240V electric heaters are ceiling-mounted and hardwired. This is usually the safest and most common location to install a garage heater.
- Wall-mounted. Many 120V and some 240V heaters are wall-mounted and can either be hardwired or just plugged in. Here the point is to get as thin a heater as possible and save on garage space.
- Portable or floor heaters. Only 120V 1500W garage heaters are portable. They will have a handle you can use to move them around. Most often, you place it on a garage floor. It is also worth mentioning that all portable electric garage heaters are plugged-in directly into a standard outlet; quite an easy installation.
Wiring will also be important. 120V heaters are easier to install than 240V heaters. This is hardwired vs plug-in electric heater consideration:
Namely, for a 120V 1500W heater you will only need a standard circuit. Why? Well, 1500W heaters on 120V will draw 12.5 amps and you usually have 15 amp breakers. That means that even a small 15A breaker will be enough for a 1500W heater (and standard 14 AWG wires).
With powerful 240V heaters, however, you are dealing with higher voltage, amps, and watts. A 5000W heater on a 240V circuit will draw 20.8 amps; you will already need 30 amp breakers and 12 AWG wires.
The biggest 15,000W heaters can draw up to 62.5 amps. You will need bigger 6 AWG wires that can handle up to 65A and multiple amp breakers. This may seem like a big electric circuit upgrade; however, to produce 15,000W of electric input and heating output, you would need ten simpler-to-install 1500W 120V heaters. That’s quite a lot of heaters and wiring.
How To Choose A Reliable Electric Heater?
Nowadays, pretty much anybody can produce an electric heater. It’s just a heating element, a fan, and wiring. However, many of no-brand electric heaters are notoriously unreliable and can break down within the 1st year of use.
The best way to ensure you are getting a reliable electric heater (be it 120V or 240V) is to look for a reliable brand with a good track record.
The reliable brands for electric heaters are:
- King Electric. This is usually considered the best electric heater brand and they make the best 240V electric heaters for garages.
- Stiebel Eltron. This is a German company most well-known for their tankless water heaters. They make exceptional 120V electric heaters as well.
- EdenPURE. They make superb good quality (heavy) 120V heaters but their price tag is considerably higher due to best reliability.
- Comfort Zone.
- Dr. Heater.
In the following lists of the best 120V garage electric heaters and best 240V garage electric heaters you will see that the selection of the best garage electric heaters is made out of only these reliable brands:
Best 120V Electric Garage Heaters
- Best 120V Electric Garage Heater With Thermostat: Stiebel Eltron 074058
- Best Portable Electric Garage Heater 120V: NewAir NGH160GA00
- Best Small Plug-In Electric Panel 120V Garage Heater: Envi LE5012P
- Very Good Space Heater For Garage That Runs On 120V: EdenPURE CopperSMART
1. Best 120V Electric Garage Heater With Thermostat: Stiebel Eltron 074058
Stiebel Eltron is a German company, specializing in electric heaters. Their Stiebel Eltron 074058 model is the best 120V electric garage heater on the market, for quite a few reasons apart from being made by Stiebel Eltron.
Namely, the 074058 heater is a standard 1500W 120V garage heater. It can generate up to 5118 BTU and can adequately heat up garages with up to 170 sq ft.
It is a wall-mounted 120V electric heater that requires minimal electric circuit requirements (it’s hardwired into the wall). You only need 15A breakers and 14 AWG copper wires which you already have (standard wiring). That means the installation is as simple as it gets, apart from portable electric heaters.
Very importantly, it has a superb external thermostat with a 41°F – 86°F temperature range. You just set the thermostat temperature, and the Stiebel Eltron 074058 will run on 100% heating output to reach it. When the garage temperature is reached, the heater will reduce the heating output to sustain that temperature and run at a much lower running cost. You can get from $0.20 per hour running cost to below $0.10 per hour running cost with this thermostat.
It also has a bunch of advantageous features including an even-heating down-draft design, booster timer on CKT, frost protection, CK trend on/off switch, and so on.
On top of that, many people love it in their garage because it is the quietest electric heater on the market. With its ultra quite fan, it will only generate up to 49.7 dB of noise output. For comparison, most electric heaters run on 55 dB, 60 dB, or more noise output.
All in all, the Stiebel Eltron 074058 is the best 120V electric space heater for a garage. It is incredibly energy efficient, very quiet, reliable and with quite an attractive price:
2. Best Portable Electric Garage Heater 120V: NewAir NGH160GA00
NewAir NGH160GA00 is a very interesting 120V electric heater for the garage. No, it’s not as reliable as #1 Stiebel Eltron or as high quality as #4 EdenPURE heater but it is ridiculously underpriced and one of the best portable electric 120V garage heaters.
The same as most 120V garage heaters, it can generate up to 1500W or 5118 BTU of heating output. This is enough to heat an up to 170 sq ft garage; you might need 2-4 of these heaters for bigger multiple-car garages.
It has the simplest installation. NewAir NGH160GA00 is basically a portable electric heater. You have a handle on top to move it around and you just plug it into a standard 120V outlet. That’s it; this is the biggest advantage (apart from the price) that the NewAir heater has.
It does have its own disadvantages, of course. Namely, the lack of an external thermostat will increase the running costs. When running it at 1500W, it will consume about $0.20 per hour (given $0.1319/kWh electricity cost). When the temperature in the garage is OK, you will have to shut it off… and then turn it on again when the temperature falls. That’s not the most convenient way of using an electric garage heater.
NewAir is also not as a reliable brand as Stiebel Eltron or EdenPURE.
However, this heater costs way below $100. It is almost impossible to get a good electric heater for less than $100. NewAir NGH160GA00 is fairly good (it even has a 200 CFM fan for quick heating) and it does have the advantage of being portable and can be plugged in anywhere.
All in all, if you need a quick and cheap (albeit not very reliable) way of heating up a garage, NewAir NGH160GA00 is a good heater to choose:
3. Best Small Plug-In Electric Panel 120V Garage Heater: Envi LE5012P
Envi LE5012P has become quite a popular 120V electric garage heater in the last few years and it’s not hard to see why. It has the most optimum thin shape for a wall-mounted garage heater and it is a plug-in model (no messing around with wiring).
As we have said earlier, these wall-mounted electric heaters for the garage better be thin. And Envi LE5012P is the thinnest wall-mounted electric space heater; it is only 2 inches thick. Effectively, it is more of a heating panel than a conventional forced-air garage heater.
It does have an external thermostat; this translates into being energy efficient. On top of that, it is one of a few plug-in models with the easiest installation. You just mount the Envi LE5012P on the wall and plug it into a standard 120V outlet.
Envi LE5012P is, however, not a 1500W electric heater. It is a 500W heater that can generate 1,709 BTU of heating output; enough to heat only 60 sq ft. If you want to heat up a garage, you will need more than 1 unit; you might need 10 of them if you have a bigger 2-car or 3-car garage. Given it only draws 4.3 amps, you can put 3 of them on the same 15A breaker.
All in all, Envi LE5012P is quite a popular choice despite only having a 500W power input. It is easy to install, quite reliable, doesn’t cost all that much but you will need quite a lot of them for adequate garage heating:
4. Very Good Space Heater For Garage That Runs On 120V: EdenPURE CopperSMART
EdenPURE CopperSMART is considered the best electric space heater on the market. This is a 20+ lbs heater made of durable materials that can be used in a garage as well. The problem with such a great heater is obviously the $400+ price tag; quite justified given the design but it’s still quite a lot.
EdenPURE heater has it all: dual high limit sensors, touch-safe front grill cover, tip-over sensor, and even a copper PTC with an auto reboot for after power outages. It is made mostly out of durable copper and will last for 10+ years easily.
Needless to say, this is a 1500W 120V electric space heater that can heat an up to 170 sq ft garage. It is not specifically a garage electric heater; it is a general-use space heater that can be used in a garage.
It also has the best thermostat with the widest temperature range. You can set it as low as 40°F to as high as 90°F. The value of this thermostat is considerably lower heating costs. You can use the remote control to set the temperature and once the set temperature is met, the EdenPure CopperSMART will reduce the electric input to only sustain the temperature.
The biggest hurdle when deciding on this heater is the $400+ price tag.
In short, EdenPure CopperSMART is superbly made out of copper and it has a smart thermostat. That, in addition to being one of the most reliable heaters, can quite justify the higher-than-average 120V electric heater cost:
Let’s have a look at more useful bigger 240V electric garage heaters as well:
Best 240V Electric Garage Heaters
1. Best 240V Electric Garage Heater (5 Models): King Electric ECO Heaters
King Electric ECO heaters are generally considered to be the best electric garage heaters. They are one of the few heaters still made in the US and have a 64+ year old tradition. Out of all electric heaters, the King Electric ECO heaters are the best ones to own.
Namely, King offers the widest range of heaters for all garage sizes:
- King KB2405-1-B2-ECO KB ECO2S is a 5000W heater for 1-car and 2-car garages. It has a heat output of 17,060 BTU and can adequately heat garages with a total square footage of up to 570 square feet.
- King KB2407-1-B2-ECO KB ECO2S is a 7500W heater for 2-car and 3-car garages. It has a heat output of 25,590 BTU and can adequately heat garages with a total square footage of up to 850 square feet.
- King KB2410-1-B2-ECO KB ECO2S is a 10,000W heater for 3-car and 4-car garages. It has a heat output of 34,120 BTU and can adequately heat garages with a total square footage of up to 1140 square feet.
- King KB2412-1-B2-ECO is a 12,500W heater for 4-car and 5-car garages. It has a heat output of 42,650 BTU and can adequately heat garages with a total square footage of up to 1420 square feet.
- King KB2415-1-B2-ECO is a 15,000W heater for 5+ car garages and big shops. It has a heat output of 51,180 BTU and can adequately heat garages with a total square footage of up to 1700 square feet.
The important thing with these bigger electric garage heaters is energy efficiency. If you run a 10,000W heater for 1 hour, it will use 10 kWh of electricity with an average cost of $1.32 per hour. That’s why King ECO2S heaters use a smart 2-stage energy-saving thermostat to significantly reduce garage heating costs.
King also uses the best-in-industry heat exchangers through which the forced air produced by the fan is passed. These spiral fins and brazed with copper and them molded into a coil configuration. This system ensures homogeneous heating (without hot spots) and facilities a high CFM airflow needed to produce 30,000+ BTU of heating output.
As all 240V electric heaters for the garage, the King heaters have to be hardwired. You can mount it on the ceiling or on the wall. You have to be aware that with such a high wattage, you will need thicker wires and bigger/multiple amp breakers. 10,000 W heater, for example, draws 42 amps; you will need two 30A breakers and an 8 AWG wire.
In every aspect but one, the King heaters are the best electric heaters to be used in a garage. That one aspect? The price. The price matches the superb reputation of King heaters; the 5000W heater costs about $900 and the biggest 15000W heater costs almost $1,500.
All in all, King heaters might be pricy, but they are the best electric heaters currently on the market. ECO2s heaters significantly reduce the running costs, are made out of extremely durable materials (with a copper blazing on the heat exchanger), and are the must-have addition to a garage in the winter if you can afford one:
2. Good 240V Alternative To King Electric ECO (3 Models): Comfort Zone CZ230ER
No one offers better or more versatile electric heaters than King. However, while those heaters are made in the US and will last for ages, the cost is sometimes too much to bear. A viable, yet lower quality, alternative are the Comfort Zone heaters.
These are 240V heaters that can produce 5000W, 7500W, or 10,000W wattage and up to 34,120 BTU heating output. With this wattage range, you can use them in 1-car, 2-car, 3-car, and even 4-car garages.
Comfort Zone CZ230ER heaters do have a thermostat for energy efficiency, overheat protection sensor and are made of quite durable materials. Obviously, King heaters are far superior, but Comfort Zone CZ230ER units are also a lot cheaper. You can get these heaters for less than $200.
The durability of the heat exchanger, however, is a bit questionable. Comfort Zone is also not as well-regarded a brand of electric garage heaters as King.
All in all, if you are looking for a similar heating output King can offer but at a lower price point, Comfort Zone is a viable choice:
3. Most Popular Old-School 240V Electric Garage Heater: Fahrenheat FUH
Fahrenheat FUH heater is something your father might have in the garage. It is a classic old-school electric heater with a good track record that is still considered one of the best 240V electric heaters in 2023.
Despite being of designed decades ago, it does have a good thermostat with a 45°F – 135°F temperature range. That means that the heater will switch to lower wattage (saving costs) when it reaches the thermostat set temperature.
This is a 5000W heater that can produce up to 17,060 BTU of heating output. This is enough to heat up garages with a total square footage of 570 sq ft, according to the 30 BTU per sq ft of garage rule of thumb.
Despite having a good track record, however, the newer King heaters are obviously more advanced and safer to use.
For wiring, you will need just one 30A breaker and 12 AWG copper wires.
All in all, with a price of about $300, the Fahrenheat FUH is a classic and tested electric heater that can still be used in modern garages:
4. Biggest 240V Electric Heater For Large Garages: Dyna-Glo Dual Power
Dyna-Glo Dual Power is a powerful 240V electric garage heater. It has a 15,000W electric output that can generate 50,000+ BTU of heating output and can heat up big 5+ car garages and shops.
With these big electric heaters, a good thermostat is vital. 15,000W heater will, when operating at 100% heating output, use 15 kWh per hour. That’s more than Tesla Model 3 uses on average. That can increase the costs of heating a garage to over $2 per hour. That’s why Gyna-Glo uses a good thermostat that reduces the wattage to 11,300W and thereby reduces the running cost of heating a big garage.
Of course, 15000W is usually too much heating output for most garages; Dyna-Glo Dual Power is specialized only for big garages and workshops.
It is hardwired and ceiling-mounted. The heater draws 62.5 amps. That means you will need to do some serious electric circuit upgrades, including triple 30A breakers.
All in all, Dyna-Glo Dual Power is a good choice for the biggest garages. It costs less than $600 and for that you get 50,000+ BTU of heating output with a good cost-saving thermostat:
5. Cheap 240V Electric Heater For Garage: Dr. Heater DR966
The best electric heaters can be quite pricy. If you are looking for a budget-friendly heater strong enough to heat a 1-car, 2-car, or even a small 3-car garage, the Dr. Heater DR966 is not a bad choice.
This is a 6000 watt 240V heater that can produce 20,472 BTU of heating output. According to the 30 BTU per sq ft rule of thumb, this is enough to heat up garages with combined square footage of up to 680 sq ft.
6000W is also an optimum heater wiring-wise. Namely, you will need only one 30A breaker (80% capacity is 25 amps) because when operating at 100% output, the Dr. Heater DR966 draws exactly 25 amps.
Dr. Heater DR966 is also ridiculously underpriced. It costs at most $200. Now, you need to be aware this is not as a reliable heater as King heaters and it can break down quite easily. That’s why the lower price point.
In short, Dr. Heater DR966 is a quick cheap solution for heating a garage but it might not last as long as you want:
As we have seen, the best way to heat a garage is with a simple electric heater. With this selection of the best 120V electric garage heaters and the best 240V electric heaters, you have all you need to figure out which electric heater to use in your garage.