Can you put a space heater on carpet? Or should you rather place them on the bare floor? And what if your floor is fully carpeted?
Many websites online suggest to never put a space heater on a carpet. A quick search already revealed quotes such as the following
“You should never sit a space heater on a carpet or area rug. The carpet will trap the heat, and the build-up of heat may cause a fire.”
temperaturemaster.com
But as an electrical engineer, I can tell you: This is an overly fearful perspective.
Quick answer: Yes, you can put a space heater on the carpet. Since heat rises to the top, it is extremely unlikely for the carpet to accumulate enough heat to catch flame. The temperatures needed to ignite carpets are much higher than what space heaters can produce. The main safety threat of space heaters is unresponsible usage. As long as you are in the same room, there is no problem with running a space heater on carpet.
You might wonder why I say you can place your space heater on carpet, while nearly everyone else out there is recommending the opposite.
In the following sections, I will explain, why you should not worry about running your space heater on a carpet and what you should do to ensure you are safe at all times.
Risk of putting a space heater on a carpet
Let’s first have a quick look at the “Never place a space heater on a carpet”-perspective. This is the fearful perspective most people have.
Most people reason that when a space heater is running on a carpet, heat accumulates between the heater and the carpet. Eventually, the heat will build up and cause a fire.
Especially thick and well-insulated carpets will trap heat, which either causes the carpet itself to catch flames, or it causes the space heater to overheat.
This perspective sounds reasonable at first. But in the next section, we will see why this fear can’t be backed up scientifically.
Why the risk is not as big as you think
Let’s see why your carpet will surely not ignite just by having a space heater run on it.
Carpets are hard to ignite
Most home fires do not originate on the floor. Carpets are relatively hard to inflame.
Let’s have a quick look at 3 different materials commonly used in carpets and their ignition and melting temperatures. The data is taken from the eco-terric flammability report:
Material | Ignition temperature (°F) | Melting temperature (°F) |
Wool | 1058 | Does not melt |
Cotton | 491 | Does not melt |
Nylon | 905 | 320 |
Polyester | 905 | 484 |
Rayon | 788 | Does not melt |
In the table above you can see the temperatures needed to ignite and melt different kinds of carpet.
All temperatures listed are definitely much higher than the surface temperatures a space heater generates. So, just through plain physics, it is already impossible for a space heater to ignite carpet.
Another point I find surprising is the very high ignition temperature of wool (honestly I thought wool would be the easiest to ignite).
The worst thing that can happen to you (as long as your space heater doesn’t explode), is that it tips over and melts parts of your Nylon carpet. But there is still no risk of fire.
Space heaters can’t ignite carpets because of the high ignition temperatures of carpets.
Space heaters have built-in safety mechanisms
As long as you bought your space heater within the last, say, 15 years, it is almost guaranteed to have built-in overheat protection.
The built-in overheat protection senses when a space heater becomes too hot and shuts it off automatically.
This prevents another disaster from happening:
Not only the carpet could ignite, but the space heater itself. With a thick carpet, the space heater has no way to get rid of the accumulated heat and can catch flames.
Right? Wrong!
First off, the carpet only covers the bottom side of the space heater. The bottom side of a space heater is naturally cool since hot air rises upwards and no space heater outputs heat downwards.
Also, the overheat protection would immediately shut off your space heater in case it gets too hot.
Your space heater catching fire through overheating while standing on a carpet is highly unlikely.
As long as you use a reasonably safe space heater, nothing can happen. I wrote a review about my favorite safe oil-filled radiator (click here to view the product).
Fires need oxygen to burn
Also, fires need oxygen to stay alive. Only the upper surface of a carpet is exposed to oxygen, which prevents the flame to nourish effectively. Most carpets you have at home are made of dense material and are densely knitted.
Trying to inflame a carpet is like trying to inflame a flat tabletop. Even though it is made of wood, which is naturally inflammable, starting a fire on it is next to impossible.
All you will end up with is burn stains.
Most carpets behave exactly the same. As long as you don’t put any inflammable liquids on them, trying to ignite a carpet is really hard.
Yes, there are some carpets that are easier to ignite than other kinds of carpets. But in general, the risk is not as big as you think it is.
Just be reasonable with your space heater placement.
Which space heaters you can put on carpet
You can put almost all space heaters on a carpet. All regular household heaters are suitable for usage on a carpet. This includes oil-filled radiators, infrared heaters, ceramic heaters, and other types of electric heaters.
It does not really matter which power rating a space heater has. Most American space heaters use 1500W of power. Europeans output 2000W of heating power. All of them are too weak to put a carpet on fire, regardless of the material.
Actually, the power is enough to ignite a fire. But space heaters distribute the heat through radiation. The power is not focused in one spot. This makes space heaters safe.
All household space heaters are generally safe to use on carpet. Of course, this does not mean you can run a space heater 24/7, even when you’re not at home.
Responsible usage is what makes a space heater safe. In a later section, we’re going to cover some safety measures you should ensure in order to prevent fires.
Which space heaters you can’t put on carpet
While you can use all regular electric household heaters on a carpet, you can’t use all space heaters in general. Some space heaters are not designed to be used in household spaces.
Unsafe space heaters are first and foremost torpedo heaters. Torpedo heaters are propane (or other fuel) powered heaters that exhaust flames! These are meant to quickly heat industrial spaces, garages, or construction sites. Torpedo heaters are not meant to be used in living spaces such as your living room or your bedroom.
Of course, there are exceptions. Especially, if you live in a remote place and don’t have access to electricity, using a torpedo or propane heater makes sense. However, in this case, you should never use them on carpets. Torpedo heaters output temperatures that go well above the ignition temperature of any regular carpet.
So, if you plan to use a torpedo heater at home, make sure to use it on a solid, non-inflammable surface.
Additional safety advice to run a space heater on carpet
Now that we know whether regular space heaters are safe to be used on carpets, let’s have a look at some additional safety measures you can take.
Don’t run the space heater in your absence
The most important rule of electric space heater usage is to never use your space heater when you are not at home or when you are otherwise absent.
This, of course, also means: Never use a space heater on carpets when you are absent.
Even though space heaters are generally safe, most house fires are caused by space heaters that were left alone running. Make this statistic your friend and always ensure space heaters are turned off when you leave the house.
Now you are well prepared to use your space heater on a carpet. There are, however, still a few nice tips I found online.
Put the space heater on ceramic flooring tiles
“Buy some 18”x18” ceramic flooring tiles from a hardware store and put those on the carpet and the heater on top”
Reddit user ArrivesWithaBeverage
The ceramic absorbs the heat and distributes it. Ceramic is known to be fireproof. If you are still worried, installing ceramic flooring tiles is a reasonable choice.
Put the space heater on an elevated surface
Alternatively, if have a stool or small table you can put the space heater on it. However, I personally dislike that chairs and stools are oftentimes not stable enough and the space heater could tip over. Putting a space heater on the floor is generally better.
Use a smaller space heater
Also, if you are still worried, you could go for smaller-sized space heaters. There are some heaters that only use 750W of power, instead of the regular 1500W. These heaters consequently also produce less heat and therefore ignite far less often.
Conclusion
Yes, you can run all regular household space heaters on carpet. Space heaters don’t simply ignite carpets. The temperatures needed to put a carpet on fire are far higher than what most space heaters produce.
In any case, the main security threat is not your space heater, but how you use it. As long as you act reasonably, you are perfectly safe.
Do not use space heaters in your absence. Evaluate on your own and based on your feelings if you can place your space heater on a carpet.
Generally, it is safe. But if you don’t feel confident, you should look for another solution such as putting ceramic flooring tiles beneath your heater.