How Many Infrared Panels Do I Need? A Complete Sizing Guide
The number of infrared panels you need cannot be determined accurately from floor area or bedroom count alone.
First calculate how much heating output each room requires. Then decide how that wattage should be distributed between one or more appropriately positioned heaters.
How Do I Work Out How Many Infrared Panels I Need?
Start by calculating the required heating wattage for each room using its dimensions, ceiling height, building type and other relevant heat-loss factors.
Once you know the required wattage, choose a heater or combination of heaters that provides suitable output and radiant coverage for that particular space.
A room requiring 1,200W does not automatically need one 1,200W heater. Depending on the layout and available heater positions, distributing the output between more than one heater may sometimes provide a more suitable arrangement.
Calculate Wattage First - Panel Quantity Second
One of the easiest mistakes when buying infrared heating is starting with the number of panels.
The first question shouldn't be:
“How many panels fit in this room?”
It should be:
“How much heating output does this room require?”
Once the required wattage is known, you can decide how best to provide it.
If you're unsure about the wattage stage itself, our What Size Infrared Heater Do I Need? guide explains it in more detail.
7 Factors That Affect How Many Infrared Panels You Need
Room Dimensions
Length and width matter, but floor area alone does not tell the whole story.
The volume and construction of the room also influence its heating requirement.
Ceiling Height
Two rooms with identical floor areas but very different ceiling heights should not automatically be treated as identical heating projects.
This becomes especially important in vaulted rooms, older properties, halls and commercial spaces.
Building Age and Construction
A modern insulated property and an older building may lose heat at very different rates.
The heating requirement should therefore reflect the building rather than applying one universal wattage figure to every property.
Insulation
Insulation influences how quickly heat leaves a building.
Better thermal performance can reduce the amount of heating output needed to maintain the intended indoor conditions compared with a higher-loss equivalent space.
Windows and Glazing
The amount and performance of glazing can influence room heat loss.
Large glazed areas therefore need to be considered when calculating the required heating output.
Room Layout
Total wattage isn't the only consideration with radiant heating.
Room shape, furniture, available wall or ceiling positions and the location of occupied areas can affect whether one heater or several heaters provide the more suitable arrangement.
How the Room Is Used
A regularly occupied living room, intermittently used home office and large commercial space do not necessarily have identical heating requirements or control strategies.
Heater selection should therefore consider the intended application as well as the room dimensions.
Don't Use One Fixed “Square Metres Per Panel” Rule
You may see infrared heaters advertised using claims such as:
“This heater covers X square metres.”
That can be useful only as a very broad indication because two rooms with the same floor area can have substantially different heating requirements.
Ceiling height, insulation, glazing and building construction all matter.
That's why IHS uses a room-based Wattage Calculator rather than relying on one universal square-metre figure.
Is One Large Infrared Panel Better Than Two Smaller Panels?
Not necessarily.
The first requirement is that the selected heaters provide appropriate total output for the room.
After that, positioning and radiant coverage should be considered.
In some spaces, one appropriately positioned heater may be suitable. In another room, distributing the required output between two heaters can provide a more practical arrangement.
May Make Sense When...
- The required output is available from one suitable model
- The room layout allows an effective position
- The occupied area can be served appropriately
- There are no major layout obstacles
May Make Sense When...
- The room requires higher total output
- The room is large or unusually shaped
- Output needs to be distributed across the space
- Available mounting positions favour more than one heater
More panels do not automatically mean more total electricity use. If two heaters together provide the same total rated output as one larger heater, the combined maximum electrical input is determined by that total wattage. The actual system design and operation still matter.
A Simple Infrared Panel Sizing Example
Imagine a room has been calculated to require approximately 1,200W of heating output.
That does not necessarily mean you must find one 1,200W infrared panel.
Depending on the available products, room layout and suitable mounting positions, the required output could potentially be provided by:
- One appropriately rated heater
- Two heaters whose combined output meets the requirement
- Another suitable combination based on the room design
The important point is that the total required output came first.
The number of heaters was then selected around that requirement and the room layout.
Panel Positioning Can Affect How Many You Need
Infrared heaters emit radiant energy towards people and surfaces within their effective area.
This makes positioning an important part of the design.
A powerful heater in a poor location should not automatically be assumed to perform as well as an appropriately distributed system.
When deciding how many heaters to use, consider:
- Where people spend time in the room
- Furniture placement
- Room shape
- Available wall space
- Available ceiling positions
- Product-specific mounting requirements
If you're deciding where the heaters should go, read our Ceiling vs Wall-Mounted Infrared Panels guide and our Infrared Heater Installation Guide.
How Many Infrared Panels Do I Need for a Whole House?
A whole house should be calculated room by room.
Avoid shortcuts such as:
“A three-bedroom house needs X panels.”
Bedroom count tells us very little about the actual heat requirement.
Instead, calculate each heated room separately and then combine the results to understand the complete property requirement.
| Room | What Should Be Calculated? |
|---|---|
| Living room | Required output, layout, occupied areas and suitable heater positions |
| Kitchen | Required output plus available wall or ceiling positions around the room layout |
| Bedrooms | Each bedroom independently rather than assuming identical requirements |
| Bathroom | Required output plus suitability of the specific heater and installation location |
| Home office | Output plus occupancy schedule and independent control requirements |
Our Can Infrared Heating Heat a Whole House? guide explains the complete-property approach in more detail.
Don't Forget the Thermostats
Working out the correct number of heaters is only part of designing the system.
You also need to decide how the heaters will be controlled.
Separate rooms often have different occupancy schedules and temperature requirements.
If those rooms need independent temperature control, they require the appropriate independent control arrangement.
One thermostat should not be assumed to provide independent temperature control across multiple separate rooms.
Read our Do Infrared Heaters Need a Thermostat? guide or compare built-in and external thermostat options.
Does Having More Infrared Panels Mean Higher Running Costs?
Panel count alone does not determine electricity consumption.
Total electrical output and operating time matter more than simply counting the number of heaters.
For example, two heaters with a combined rated output of 1,200W have the same maximum combined electrical input as a single 1,200W heater when all are drawing full rated power.
Actual energy consumption then depends on factors such as:
- Operating hours
- Thermostatic cycling
- Temperature settings
- Building heat loss
- Zoning
- Occupancy
- Electricity tariff
See our infrared heating running-cost guide for the full explanation.
What If You're Still Deciding Whether Infrared Is Right for You?
Before calculating an entire property, it can be useful to understand whether infrared's characteristics suit what you're trying to achieve.
We've created two decision guides for exactly that:
If you're comparing infrared with other electric systems, you can also read:
Sizing Infrared Heating for Houses and Flats
The same basic sizing principle applies whether you are planning infrared heating for a detached house, terrace, apartment or individual room:
calculate the heating requirement of the space before choosing the heaters.
However, the available heating options and installation considerations may differ between property types.
If your property has no gas connection, read: Best Heating for a House Without Gas.
For apartments, we've also created: Best Electric Heating for a Flat.
Does the Number of Panels Affect Installation Cost?
Potentially, but heater quantity is only one part of the installation.
The final project can also depend on:
- Heater type
- Mounting position
- Controls
- Electrical work
- Accessibility
- Existing electrical installation
- The number of separately controlled heating zones
We cover this separately in How Much Does It Cost to Install Infrared Heating in a House?.
Infrared Panel Sizing FAQs
How many infrared panels do I need per room?
There is no fixed number. First calculate the required heating wattage for the room, then select one or more suitable heaters based on total output, room layout and positioning.
How many infrared panels do I need for a three-bedroom house?
Bedroom count alone is not enough to size the system. Each heated room should be assessed individually because dimensions, ceiling height, insulation, glazing and construction can differ throughout the property.
Can one infrared panel heat a whole room?
It may be possible where one suitable heater provides the required output and can be positioned appropriately. Larger or differently shaped rooms may be better suited to more than one heater.
Is it better to have one large infrared panel or two smaller ones?
Neither arrangement is universally better. Total required output, room shape, radiant coverage and available mounting positions should determine the most appropriate arrangement.
How do I calculate what size infrared panel I need?
Start with the room's dimensions and relevant building factors to estimate its required heating output. See our infrared heater sizing guide for more detail.
Do more infrared panels use more electricity?
Not simply because there are more units. Maximum electrical consumption is determined by the combined wattage operating at a particular time, while actual energy use also depends on operating hours, thermostatic control and building heat loss.
Can I use infrared panels throughout my whole house?
Infrared heating can be designed as a multi-room system when each room has sufficient calculated output, suitable heater positioning and appropriate controls. Read our whole-house infrared heating guide.
Work Out How Many Infrared Panels You Need
Don't guess from room area or choose the panels first.
Calculate the heating requirement, establish the wattage and then decide how that output should be distributed throughout the room.
Read our Complete Infrared Heating Guide, browse our infrared heating collections or speak to the IHS team about your heating project →