Determining The Number Of Patio Heaters You Need

Picture it, a gorgeous night with a slight chill in the air. A night that would be well spent cozied up outside with a cup of hot cocoa staying warm with the help of a patio heater. But how many patio heaters are necessary to heat your desired space?

When determining how many patio heaters you’ll need, there are a few things to keep in mind. First off, there are plenty of options to choose from based on style or capabilities.

Natural gas, electric, and propane heaters are the primary options available for patio heaters. These options are based on the type of fuel source used, and each has pros and cons that will be explored.

Understanding something called British Thermal Units or BTU will be essential in determining exactly how many patio heaters you will need. Based on how much space you are looking to heat, more BTUs will be needed. Your needs will also vary based on whether space is covered or uncovered.

In general, you will need one patio heater for every 1500-2000 square feet. Whereas an uncovered space will require one patio heater for about 300-square feet of space. 

Lastly, once you’ve acquired the patio heaters you’ll need to be mindful of where you place them. Caution needs to be taken when setting them up and using your heaters. Placing them too close to certain flammable materials may be dangerous.

Furthermore, certain types of heaters will need to be arranged close to a ventilation system if they are being used indoors due to carbon monoxide emissions.

Determining how many patio heaters are need by looking at multiple patio heaters lined up

Types of Patio Heaters

Based on the patio heaters fuel source there are three different types of heaters to choose from. In exploring each of these options, it’s important to evaluate factors such as installation, energy efficiency and general upkeep of each one.


Propane patio heaters are not only easy to install, but they heat up quickly. All you will need for your propane heater is a propane tank which can last for up to ten hours.

Plus, if you’re a grill master you probably already have a propane tank on hand. Propane heaters do not require professional installation, but they do need to be replaced and exchanged once they have emptied.

A propane heater will need to be kept in an open or uncovered area due to the product of carbon monoxide.

Natural Gas

Natural gas heaters do require professional installation and mindful placement as once they are set up they are difficult to move. This heater will need to be connected to your home’s natural gas line.

Once installed though, these heaters are the most cost-effective option out of the three choices. A natural gas heater will need to be kept in an open or uncovered area due to the product of carbon monoxide.


Electric gas heaters are simple to install and do not require professional installation. With the electric heater, you won’t need to worry about replacing the propane tank or tapping into your home’s natural gas line.

Electric heaters can work in numerous spaces without the threat of carbon monoxide poisoning. However, you will need to keep in mind the energy used with your heater adding to your power bill. Furthermore, electrical heaters are the slowest to heat up of the three options.

Assessing the fuel sources, one might ask which one is best? breaks it down a few different ways. If you already have a propane tank or gas line set up in your home, then a Natural Gas or Propane Patio heater might be the most convenient option. 

However, keep in mind that electric heaters offer the flexibility of customizable heating in that they have more options other than on and off. 

In researching these three options, cost and efficiency can be deal-breakers, so it’s best to research how much fuel sources, such as electricity and gas, will cost in your area

Understanding British Thermal Units

Now that you have an idea on the type of patio heater you will need, it’s time to determine exactly how many you will need to heat your space. To maximize the efficiency of your heaters as well as actually heat your space, you’ll need to become familiar with British Thermal Units or BTU. 

According to the U.S. Energy Information Administration, BTU is “is a measure of the heat content of fuels or energy sources. It is the quantity of heat required to raise the temperature of one pound of liquid water by 1 degree Fahrenheit at the temperature that water has its greatest density.”

BTUs are not only used for patio heaters, but this unit of measurement is also associated with heat pumps, air conditioning, and various heating and cooling mechanics in a home.

So what does this mean? In short, the more area that needs to be heated the higher the BTU will need to be.

The BTU is typically listed with the patio heater so you know how much heat it will be emitted as well as how many heaters will need to be purchased.

While patio heaters come in different sizes, the average standing heater emits about 40,000 BTUs. With smaller models available as well, it’s important to check the BTUs to understand how many you will need.

Considering how your patio heater emits its heat, for example in a circular area, you may require several heaters based on how much space you are attempting to heat.

With options like wall-mounted heaters oscillating heat and pushing heat in one direction, you may require multiple heaters whereas, standing heaters that radiate heat in a circular pattern could heat larger areas.

How Many Patio Heaters You Actually Need

There are plenty of options when choosing the type of patio heater you want along with the pros and cons of each. Installation, energy efficiency and general upkeep of each one will need to be taken into account for each option.

Propane and Natural gas heaters both emit carbon monoxide and will need to be kept in a well-ventilated area, while electric heaters are the slowest to heat up and could be a strain financially.

To determine exactly how many patio heaters you actually need for your space, you’ll need to take notice of the BTUs or British Thermal Units noted on the heaters.

This unit of measurement for both heating and cooling appliances considers the energy emitted as well as the square footage of the space. Simply put, the more area that needs to be heated the higher the BTU will need to be.

With the average standing heater emitting 40,000 BTUs, at least one will be able to heat a covered area of about 2000 square feet. Of course, if the space in question is uncovered you may need two or more based on the square footage.

Now that you’ve decided what kind of heater and how many you will need, you can set them up in your space and begin enjoying your patio heaters.