How Much Heat do Patio Heaters Give Off?

The amount of heat output depends on the size of the patio heater. Patio heaters are manufactured in different sizes and each size has its own amount of heat output. The amount of heat produced is measured in British Thermal Units (BTUs). Currently, the smallest patio heater can give out 5000 BTUs while the largest patio heater can give off 34000 BTUs

What Size of Patio Heater Do You Require? 

The size of your patio is the main determining factor for the size of patio heater you need. However, there are other factors such as weather conditions, the number of patio users, and the duration the patio is in use. The formula below will help you to determine the size of the patio heater which is the best for your patio.

Cubic feet of your patio area X desired temperature = BTUs needed 

You can choose to have one patio heater that will give you all of the needed BTUs or buy several patio heaters that sum up the needed BTUs. You can use the table below to decide on the best patio heater. 

A table showing area in square feet and the amount of heat needed in BTUs 

Area in square feet BTUs needed 

Factors to Consider Before/When Buying a Patio Heater 

  1. Size of your patio 

This is the main determining factor. Because the size of your patio is what determines the size of the heater you have to buy according to the amount of your desired temperature. 

Use the table above to choose the best patio heater. If your patio has many corners or turning points, it is best if you buy more than one heater that sums up the needed amount of heat. 

You should note that many heaters consume more power. 

  1. Source of power 

Patio heaters can either use electricity, propane, or natural gas. Each power source has its own advantages and disadvantages, so choose one that is best for you. 

Heaters that use natural gas are expensive to buy and install because they need a professional to install. But on the other hand, they are cheap to use and maintain. They are not easy to move around because they are fixed on a gas line. 

Patio heaters that use propane are easy to install because they do not require a professional to do so. They have a propane tank that is easy to replace when it runs out. They can be moved around when the need arises and they heat up very fast. 

The only problem is that they are expensive in the long run because you have to replace the propane tank periodically. 

Patio heaters that use electricity are expensive in the long run and they take time to heat up. They can only be used close to a power outlet because they have to be plugged in. However, they are the only patio heaters that are safe to use in an enclosed space. 

  1. The design of the patio heater 

Patio heaters can be designed to be used on the floor, to be hung on the wall, or to be placed on the table. Choose a patio heater design that is most convenient for you. 

Floor heaters are in most cases tall and thin and use gas as a source of power. Floor heaters also give off a good amount of heat and heat up faster.  

Table heaters are small and are placed on tables, stools, or stands. They are used in limited spaces and they can either be electric or gas. 

Hanging or wall patio heaters save a lot of floor space. They produce enough heat to keep you warm. They are electric and easy to install. 

  1. Cost 

The size, type/design, and fuel of a patio heater determine the cost of buying and long-run maintenance. Natural gas heaters are expensive to purchase and install but they are cheap in the long run. Propane heaters are cheap to buy but expensive to replace the propane tank. 

Electric heaters are cheap to buy and easy to install, but they are expensive in the long run, moreover, you must have an electricity connection to use them. 

  1. Safety 

A patio heater is an object producing heat and safety is an important consideration. It needs to be handled with care or else it can cause a disaster. 

If you stay in areas that have occasional gusts of wind, try to have a patio heater that can withstand this or reinforce the heater on the ground with sandbags or water bags. 

Gas heaters should be used in open spaces. Electric heaters are the safest but do not place them on flammable objects. 

Other Important Considerations 

Choose a patio heater that is easy to assemble. Get a heater that is easy to connect onto the power source and has few parts to put together. A heater with too many parts can be hard to put together. And if a heater is poorly assembled it can be a fire hazard. 

You should also consider the weather of the area you stay in. If your area receives strong winters and a lot of rainfall, buy a more powerful heater that can handle these conditions. 

You can also consider the aesthetics, elegance, and beauty the patio heater will add to your patio. Although this is not an important consideration, consider the functionality of the heater then consider the aesthetics. 


Many patio heaters offer a varied amount of heat. If the patio heater gives excess heat then it will become uncomfortable hence not serving its intended purpose. The heat capacity of a patio heater is always indicated on the heater hence calculating the needed amount of heat is important. Nowadays the smallest patio heater can give about 5000BTUs while the largest can give 34000 BTUs. 

The size of your patio is the most important consideration before purchasing a patio heater. However, there are other important factors that should also be considered. They include the safety of the patio heater, cost, design, source of power, and weather.