A cold garage is never fun to work in! Too much cold may be damaging to your vehicles as well. With a proper heating system in place, you can work comfortably in your garage during cold winter days and keep your vehicles in tip-top shape.
You may be wondering, “What size heater do I need for my garage?”
Well, the easiest way to determine the heater size for your garage is by multiplying 10 watts to the total floor space in square foot units. So, if you have 600 sq. ft. floor space, you would need a (600×10) 6000-watt garage heater.
There are a few more ways of calculating the heater size, all of which are discussed below. Keep reading!
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What Size Heater Do I Need for My Garage: Methods to Estimate
This section will detail the methods you can employ to estimate the garage heater size.
Method 1: By Wattage
This is the = method we were talking about earlier. If you do not want to spend much time or effort to get a suitable garage heater, measure out the floor space of your garage. You can do it by multiplying the floor-length by the floor width.
So, for example, if your garage floor is 24 ft in length and 20 ft in width, the floor space would be 480 square feet. Then, simply multiply the floor area with 10 watts to get a rough idea of the heater size you would need. In the same example, you would need a heater with 4800-watt power (because 480 multiplied by ten is 4800).
Method 2: By BTU (Rough Estimate Method)
This is where it gets a bit trickier. BTU, or British thermal unit, is often used to rate gas heaters. 1 BTU equals the amount of energy you will need to exert to heat 1 pound of water by 1 degree – this is equal to roughly 1055 joules.
To get a rough estimate of the BTU your garage needs, find the amount of wattage it requires following the first method. Then, simply multiply the number by 3.41.
In our previous example, 4800 watts multiplied by 3.41 equals 16,368 BTUs. You can get a garage heater close to this number.
Method 3: By BTU (Most Accurate Method)
For the most precise measurement possible, you need to calculate your garage’s air volume in cubic feet & the temperature rise. You will also need to consider the insulation (or lack thereof) in your garage’s walls. Here’s the step-by-step process to follow this method.
Finding the Temperature Rise
Start by figuring out the temperature rise of your garage. This is essentially the degree to which the garage should be heated to achieve your desired room heat level. To find this, you need the average coldest temperature of your area and the optimal garage temperature that you want.
Subtract the former number from the latter. For example, in Clinton, Iowa, the average lowest temperature is 14 degrees Fahrenheit, according to U.S. climate data. So, if you wish to maintain a temperature of 68 degrees F in your garage, your temperature rise would be 68 – 14 = 54 degrees F.
Measuring the Required Volume
Measure the cubic volume space you want to keep warm. It might be your entire garage room or only a specific part where you park your car. Multiply the height, width, and length of the area to find the volume.
For example, a garage with the length, width, and height of 24 ft., 22 ft., and 8 ft. would have a volume of 24 x 22 x 8 = 4224 cubic feet.
Estimating the Degree of Insulation
Now you have to estimate the degree of insulation in your walls. The recommended amount of insulation varies by region to region. In extremely cold areas, the recommended R-value of walls is 25-30, whereas, in scorching places, it is 13-15.
Find the recommended R-value of your area from the internet.
The degree of insulation is estimated based on how greater or lower it is from the recommended value. If your room has no insulation, use a 5 rating. The rating is 1.5, 1, and 0.5 for weak, average, and strong insulation, respectively.
Placing All the Numbers into the Formula
Once you have all the required numbers, use the formula below to find the number of BTU required for your garage
(Degree of Insulation*Volume for Heating*Temperature Rise)/1.6=BTU
For the room from our example, let, it has average insulation. The BTU would be –
And to find the required wattage, divide the number by 3.41, which results in 41,806 roughly.
It is unlikely for electric garage heaters to go that high of wattage. So, you need to install a gas garage heater, get multiple electric heaters, or increase your walls’ insulation.
Types of Garage Heaters
You will find two types of garage heaters in the market. They are explained below:
Electric Garage Heater
This is the most common type of garage heater. It works by using a metal conductor. Electricity passes through the metal implement, which heats the air surrounded by it.
How much heat will be generated depends directly on how much current is applied to the metal or how much electric resistance it has.
And the dissipation of this heat depends on two things – fans and infrared rays. Fans help to move around the heat. Infrared rays get absorbed into the solid objects situated in a garage, making them very useful in garages with low insulation.
Benefits of this kind of heater include being lightweight, no open flame, fast heating, higher efficiency, no wase fumes, simple thermostat control, etc.
Natural & Propane Gas Heater
In these kinds of heaters, natural gas such as propane is fed in a gas valve located inside. The gas valve gets ignited with a pilot flame or a sparker. Then the gas burns and warms a heat exchanger, which in turn activates a fan. The fan blows air through the heat exchanger, which heats the air up.
This air then warms up the garage. Some gas heaters contain an infrared tube of low intensity instead of a fan. The tube absorbs the heat and then emits infrared rays.
Benefits of using a natural and propane gas heater include powerful capacity, fast heat, cheaper operation cost, more extensive coverage, wider size options, durability, etc.
We hope we were able to explain the answer to your query –“What size heater do I need for my garage?” well. Follow our methods to calculate the heater size you need. Then go through the possible options to decide on the most suitable garage heater for yourself.
I hope the heater keeps you and your beloved cars warm throughout cold winter nights. Until the next time, ciao!