Use our heat output calculator to estimate the right size wood burning stove, gas fire or electric fire for your room, or check room suitability for a bioethanol fire.
Fire & Stove Heat Output Calculator
Calculate what size wood burning stove, gas fire or electric fire may suit your room, or check your room volume when considering a bioethanol fire.
Enter Your Room Details
Enter the dimensions of the room where the appliance will be installed.
Wood Burning Stove kW Calculator
Estimate the approximate heat output your room needs from a wood burning stove.
Gas Fire kW Calculator
Estimate the approximate heat output required when choosing a gas fire for your room.
Electric Fire Room Size Calculator
Compare your estimated room heat requirement with the heater output of an electric fire.
Bioethanol Fire Room Size Calculator
Calculate your room volume and compare it with the minimum room volume specified for the bioethanol fire you are considering.
What Size Fire or Stove Do I Need?
Choosing the right heat output helps ensure your appliance is appropriately sized for the room. A fire or stove that is too small may struggle to provide the desired warmth, while an unnecessarily powerful appliance can make the room uncomfortable.
As an initial guide, the calculator uses approximately 1kW of heat for every 14m³ of room volume at a temperature difference of around 21°C, with an adjustment for the insulation level selected.
Wood Burning Stove Heat Output
Wood burning stoves are available in a wide range of nominal outputs. Once you have calculated the approximate requirement for your room, compare the result with the stove manufacturer’s nominal output and operating range.
Gas Fire Heat Output
Gas fires normally state both gas input and heat output. For room sizing, heat output is the important figure because it represents the useful heat delivered into the room.
Electric Fire Heat Output
Electric fires commonly combine a decorative flame effect with a heater. The physical size of the fire does not necessarily indicate its heat output, so check the manufacturer’s stated heater rating and compare it with your estimated requirement.
Bioethanol Fire Room Size
Bioethanol fires require a different approach. Manufacturers specify minimum room volumes for individual fires or burners, so there is no single room-size rule that applies to every bioethanol appliance.
Use the calculator to determine your room volume and compare it directly with the minimum room volume stated in the manufacturer’s technical information.
What Affects the Heat Output Required?
- Room length, width and ceiling height
- Property age and construction
- Wall, roof and floor insulation
- Size and type of glazing
- Number of external walls
- Draughts and air leakage
- Open-plan adjoining spaces
- Other heating within the room
For more information, please come in and see us in our showroom.
Insulation Overview
Before selecting a stove, evaluate how effectively your home holds warmth.
- Poor insulation: Homes built before roughly 1950 or those with single-pane windows, noticeable drafts, and minimal loft or wall insulation typically lose heat rapidly.
- Moderate insulation: Common in properties from the 1990s, where double glazing and partial insulation provide a middling level of heat retention.
- High insulation: Newer homes constructed from around 2008 onward are generally built to be airtight and meet modern thermal standards, allowing them to maintain heat efficiently.
How to calculate the kw heat output required for a room manually?
To determine the room’s cubic space, multiply its width, height, and length. As a general guideline, divide the resulting cubic space by 14 to obtain the required kilowatt (KW) output for the room.
What should I bare in mind when choosing a log burner?
Consider the insulation quality, easily assessable through our calculator, as well as factors such as the number of radiators, desired room temperature, openness of the space, presence of underfloor heating, and the intended purpose of the stove, whether it’s meant to serve as the primary heat source or purely for aesthetic effect.
- The amount of insulation in your home (factored in our calculator)
- Determine the number of radiators in the room
- Specify the desired room temperature
- Consider the openness of the space
- Account for the presence of underfloor heating
- Define the stove’s purpose: main heat source or aesthetic effect
These considerations ensure a comprehensive approach to selecting a stove that aligns with your specific heating needs and preferences.
Why is it important to get the kW heat output correct?
Choosing the correct kW heat output for your log burner is crucial to ensure optimal performance and efficiency, preventing the risks of underfiring or overfiring.
Incorrect heat levels can not only diminish the stove’s lifespan but also lead to potential issues such as tar buildup in the chimney, emphasising the importance of selecting the right capacity for your specific room.
What stove should I purchase based on my result?
Choose a category of the leading wood burning stoves based on kW heat output using the links below:
- Small: 3kW+ Wood Burning Stoves
- Average: 5kW+ Wood Burning Stoves
- Large: 8kW+ Wood Burning Stoves
- Extra Large: 11kW+ Wood Burning Stoves
Or view All wood burning stoves
Calculate the kiloWatt power needed to heat your room
Related Article: Choosing the Right Size Log Burner: A Comprehensive Guide
Our stove calculator even provides links to stoves that are genuinely suited to your space. Try it out below, and follow our concise guide to heat output (kW), size and installation for further information.
