Having the right amount of infrared wattage for a room makes all the difference. Therefore, I put together a calculator where you can easily fill in the length, width, and height of your room to get the required wattage. Since the required wattage differs per type of room, you can select what type of room you are calculating for.
Wattage calculator based on room size and type
You can use the following calculator to easily determine the required wattage based on the type of room and its size. The calculator on the left is for room size in feet. The right one is for room size in meters.
The calculator needs the length, width, and height of your room. If you can’t easily measure the height, no problem, I filled out the most common and therefore most likely height already! If you don’t know how to measure the length and width of the room, you can simply measure the number of steps you take from one end to the other. Every big step is one meter (3 foot lengths is one meter).
Additionally, the calculator requires you to select the room type you are calculating. Also, an indication of how well the room is insulated is required. If you do not know how well the room is insulated, I recommend checking the average box.
The required wattage for a standard living room
If you just want to know what an average living room requires, here you go:
- a standard US living room is 330 square feet (31m2)
- the standard height in the US is 9 feet
- a living room requires 7 watts per square foot when properly insulated (this assumes 9 feet high)
330 square feet times 7 watts = 2310 watts
Different rooms require different wattage
The calculators above already took into account everything you need, including the type of room and insulation value. Nonetheless, here are the required wattages of infrared you need per square foot for every room type. On top of that, this table shows the required wattage per room type for regular (non-infrared) heating.
This table is based on information from an infrared heaters supplier and assumes excellent insulation. If you have average or poor insulation, I recommend multiplying the required wattage by 1.15 for average insulation and 1.25 for poor insulation.
|Room type||Infrared heating: wattage |
per sq. ft (0,1 m²)
|Regular heating: wattage |
per sq. ft (0,1 m²)
|Living room||7 W||10 W|
|Bedroom||4.5 W||6.3 W|
|Bathroom||9.3 W||13.3 W|
|Closed porch||9.3 W||13.3 W|
|Open outdoor area||28 – 56 W||Warm air cannot heat an outdoor area|
I highly recommend trying an infrared panel yourself. Amazon.com offers excellent infrared panels starting from only 199$, check it out here.
Additional factors that can influence the required wattage
The calculator in this article gives an indication of the wattage that is required for your room. However, it cannot give a very precise answer because there are too many factors at play. Additional factors that determine the required wattage include:
- high humidity levels (high humidity increases our feeling of cold during winter and warmth during summer)
- outdoor temperature (large temperature difference increases heat loss)
- wind speed of outdoor air (wind increases heat loss through the walls)
- drafts and air leaks
If you have one or more of the issues stated above you will need additional heating to be comfortable.
I wrote an in-depth article about the energy use of infrared heaters. It includes their efficiency as well as the running costs. You can find it here: Infrared heaters energy use (costs, efficiency, W/sq. ft.)