Space heater buying guide

A space heater is a type of additional heating device designed to be used alongside your main heating system. Space heaters may operate using different power sources such as gas, petrol, bioethanol or, more commonly, electricity. These portable devices may be mounted on feet or wheels.

Their size, shape and design will vary depending on the heating technology used and power they produce.

Space heaters can be really practical for combating the temperature variations between seasons. For example, you can switch on a space heater at the start of winter before firing up your whole heating system or at the end of winter when you maybe don't want to have your system running anymore.

These portable heaters also mean you don't have to set up a permanent heating system in a room where it is not necessary such as a guest room or workshop. They allow you to increase the temperature of your home during very cold spells and/or to make up for an inefficient central heating system.

A space heater that doesn't rely on electricity (such as a paraffin heater) can provide a secondary heat source in case of power cuts.

There are several different types of electric space heaters on the market. The heat output of these devices varies depending on their type of heating technology and heat distribution.

Convector heaters

These devices heat up quickly and heat by convection. Most convector heaters are lightweight and mounted on feet, and some models are equipped with fans.

Oil-filled radiators 

These storage heaters are filled with heat transfer fluid and release radiant heat. They heat up less quickly than other models but are more cost-effective to run as they release heat even after they have been switched off. Oil-filled radiators are heavy and are usually mounted on castors.

Fan heaters 

These heaters are lightweight and send out heat via a fan which is housed behind an electric element. They are small, lightweight and can be placed on a counter top or shelf. They heat up quickly and are suitable for small, well-insulated rooms.

Ceramic heaters

These devices release radiant heat and can also be equipped with a fan for more efficient heat-up times. Heavier and more fragile than fan heaters, these heaters must be placed on a flat surface.

Panel heaters

These heaters are lightweight and take up as much room as convector heaters, but release radiant heat instead. Mounted on wheels, these heaters are popular as they offer instant heat.

Fireplace heaters

These heaters can be fixed in place or freestanding and offer a range of design options from traditional to modern. Fireplace heaters are designed to fit seamlessly into homes and also provide decoration.

Heated towel rails

Electric towel rails function in a similar way to space heaters. However, they are considered part of your central heating system if powered by hot water from the boiler. Electric towel rails can also be programmed. Towel rails can be fixed in place or free-standing and vary in size. These heaters release radiant heat.

In general, gas space heaters are bulky, less attractive and usually require a 13 kg gas bottle to function. It is sometimes possible to use a 6 kg gas bottle but you will have to adapt your pressure regulator accordingly. Gas space heaters do not require an electrical connection and are usually mounted on wheels.

Catalytic gas heaters

These heaters work by radiant heat technology. They are mainly used in large rooms thanks to their efficient heating capacity and size.

Infrared gas heaters

Infrared gas heaters are as bulky as catalytic heaters. The gas is distributed and burned on a ceramic tile producing convective and radiant heat transfer. These heaters are more attractive and are used indoors.

Blue flame heaters

Less common than the two above-mentioned heaters, blue flame gas heaters feature stainless steel burners and produce heat by convection and radiation. These heaters take up quite a bit of room and are comparable to catalyst heaters in terms of appearance.

Gas site heaters

Gas site heaters are space heaters designed for use on work sites or in well-ventilated workshops or garages. However, you will have to work close to the heater as they are only designed to produce low intensity radiant heat. These heaters are connected directly to a gas bottle via a pressure regulator and hose.

There are two different types of kerosene space heaters: conventional and forced-air.

Conventional kerosene heaters

Conventional kerosene heaters may feature one or two burning chambers; the latter models are more cost-effective to run and offer more efficient performance. These heaters do not require electricity to function, offer variable heat settings and generally operate using two LR20 batteries which are used to light the flame. They can operate time for around 15 hours at a time but the wick must be replaced regularly. Designed to produce radiant heat, these models are rather heavy and can be placed on the ground

Forced-air kerosene heaters

These heaters use both kerosene and electricity to run inverter technology. They can be programmed (with delayed start up to 7 days), self-regulate as soon as a set temperature is reached and feature a fan system. They are also more attractive and produce less odour than conventional models.

Bioethanol heaters are best for those more interested in design than energy performance! They can freestanding or fixed in place but are not recommended for households with young children. They operate using bioethanol and can only be used in a well-ventilated room. It's possible to find fairly large models that can be placed on or fixed to a flat surface, such as a coffee table.

All heaters vary in terms of heating technology, shape, weight and size. These factors make certain models better suited to certain rooms.

In the grand scheme of things, there's nothing stopping you from using a bioethanol heater in a garage or a kerosene heater in a bedroom. However, some space heaters are simply better suited to certain room types owing to differences in performance, thermal comfort, odour emission (however slight), heat distribution and design.

It is easy to calculate the right power rating for your space heater – it all depends on the size or volume of the room where it will be used. You should account for roughly 100 watts (or 0.1 kW) per m². First, you'll need to calculate the size of the room by multiplying the length by the width of the room in metres. Next, multiply this number by 0.1 kW to find out how much power you need.

If you want to calculate based on the volume of the room you plan on heating, you will have to multiply the length and breadth of the room by its height before multiplying the result by 0.04 kW.

If you intend to use your space heater in several rooms, make your calculations in line with the largest room it will be used in and opt for a model with variable heat settings.

1. Be sure to carefully calculate the power rating required with as much accuracy as possible and measure your heater up to the largest room it will be used in.

2. Choose a space heater with several heat settings so that it can be used in several different rooms.

3. In order to heat up a bathroom quickly, go for an electric heater equipped with a fan. It's worth noting that electric heated towel rails occasionally offer this feature.

4. Bioethanol fireplaces and conventional kerosene heaters are not recommended for households with young children.

5. If you are looking for a space heater for a bedroom or living room, electric fireplaces offer the most attractive option.

6. If you plan on purchasing a kerosene heater for a smaller room and you're not terribly handy, opt for an electric model rather than a conventional one or think twice about your decision as the cost of paying someone to replace the wick and ignition system can be high.