Can A Garage Heater Be Too Big? (Six Factors)

Estimating the right garage heater size can be a challenge.

This article will take you through simple measurements to establish the right size for your garage. 

So, Can A Garage Heater Be Too Big For Your Garage?

A too big garage heater is inefficient when heating your garage. A garage heater that is too big for the room will continue heating beyond the set temperature point, thus wasting your money and energy on the power you cannot use. On the other hand, a garage heater that is too small will run for extended periods, trying to heat your garage beyond its capacity.

Indeed, the larger the garage heater, the bigger the size.

A too big heater in a limited space can be burdensome and hard to mount.

So before you get to the store to buy a garage heater, you must get the correct wattage to avoid throwing your money into a loss-making installation.

Six Considerations Before Buying a Garage Heater

To achieve the best results, here are essential factors to consider before purchasing a garage heater:

1. Heating Consistency

You need to determine if you want consistent heat inside your garage or you need a heating system that can be turned on and off when required.

The heating units are very much available if you have a good natural gas or electricity supply.

2. Total Garage Space

The size of your garage matters a lot when getting a suitable heating unit.

Actually, your garage’s space and size determine the size of the heater to purchase.

A large garage will need a big heater whose heat output is adequate to raise the temperature of your garage to the level that is needed.

3. Winter Temperatures

When it gets freezing, you need a reliable heater that will meet heat demands in your garage during the cold season.

If you live in colder climatic areas, the outdoor temperature can be pretty low, reflecting the level of chill in your garage.

Therefore, you should factor in the lowest season temperature and buy the type of heater that suits such situations and the garage space.

4. Average Seasonal Temperatures

You should also consider the average seasonal changes in temperature.

For instance, if the temperature drops to minus ten degrees Celsius during the cold season and you wish to keep your garage at a relatively constant temperature of forty degrees Celsius, you will need a heater that will be able to generate heat of fifty degrees.

5. Cubic Footage Measurement

You will need the cubic measurements of your garage when calculating the size of the heater for your space.

To get the cubic footage, take the square footage of the garage floor and multiply it by the height of the ceiling.

For example, if your garage has a square footage of 500 and a 12-foot ceiling, its cubic footage is 6000.

6. Insulated Or Uninsulated Garage

An Insulated garage retains a lot of the heat. It contains heat better than the Insulated garage.

A non-insulated garage will lose a lot of heat, and therefore you will have to consider buying a larger heating unit to compensate for the heat loss through the walls.

You can easily factor in insulation when calculating the size of the heater to buy.

How Can You Estimate The Correct Garage Heater Size?

First, you need to guess the total wattage amount needed, by multiplying the total square of your garage by 10.

For example,  if your garage has a floor space of 600 sq feet, you can easily estimate the required wattage by multiplying by ten, i.e., 600 X 10 = 6000 watts for an electric heater.

Secondly, you can estimate the right size of the gas heater by multiplying the wattage you have calculated by 3.41.

If you obtained 6000W, multiply as 6000 X 3.41 = 20469 BTUs.

Calculating BTU

To get the right heater, you will have to use the BTU method to best estimate the size of your heater.

It is a complicated but more accurate method. It puts into consideration the level of insulation in your garage.

First, Determine The Temperature Level

Then measure the cubic footage of your garage to determine the volume of space you need to be heated. Calculate this by multiplying the square footage by the ceiling height.

Secondly, Estimate The Garage Insulation

Check the recommended levels of insulation in your region.

Garage walls in icy climatic areas need an R-value of 25 to 30, while walls in hot climates require an R-value of 13 to 15.

The insulation levels are assigned based on how far below or above it is from the proposed average.

So, if your garage walls are well insulated, use the value of 0.5 in your calculation, and for average insulation, use 1.0. But if your garage has weak or average insulation, use 1.5.

For a garage wall with no insulation, use a rating of 5.

Lastly, (Insulation Quality) x (Total Cubic Feet) x (Total Heat Raise) = the BTU requirement.

The figure you obtain is an estimate of the garage heater rating. It is easier to approximate the rating of the heater you will purchase from here.

If you live in frigid climates, don’t forget to add 10% to the BTU calculation you obtain. And to convert BTU into Watts, divide it by 3.41.

The Five Types of Garage Heaters

1. Electric

This type of heater transforms electricity into heat.

The heat produced is proportional to metal resistance multiplied by the current square.

These heaters are manufactured in both more permanent and portable products. Electric garage heaters need a 240V outlet and breaker strength of 20 Amps.

2. Fuel

Fuel-powered heaters generate heat using propane, kerosene, diesel, or natural gas.

Fuel is fed through a gas valve within the heater and lit by a sparker.

Once ignited, the burning fuel heats the heat exchanger, turning the fan that will spread the heat from the heater to the rest of the garage.

3. Radiant/Infrared

Radiant heat is adequate for direct heating. It warms items close to it instead of warming the air.

4. Forced Air

The forced air unit heater sucks cold air, warms it, and forces it into the garage space using fans.

5. Convection

The Convection heater functions in the same way as the forced air heater except for the fans. It relies on natural air circulation to spread heat within the garage. It is highly effective, quiet, and very clean.

How to Make Your Garage Heater Cost-Effective

A garage heater is an appliance you cannot do away with.

The extra heat is an excellent source of warmth in the garage during winter when the weather is chilly. But the cost of heating can be unbearably high.

Here are a few tips to help you reduce heating costs:

  1. Insulate your garage windows and the door to avoid heat leakages.
  2. Apply sealants to the cracks in the walls and on the floor.
  3. Check for leaks in the door connecting the garage and the main house and seal them with weather stripping.
  4. The concrete floor absorbs a lot of heat. Insulate it with foam board and apply a water-resistant material like vinyl.

Final words

Finding the right size heater for your garage should not be a problem anymore.

You can easily estimate the correct wattage for your garage heating need through simple calculations.

A model that’s too large takes up a lot of space and wastes energy by generating more heat than desired.