Kitchen BTU Calculator
About Kitchen BTU Calculator
A kitchen is the one room where floor area alone gives a misleading answer, because the largest heat sources in it do not scale with the size of the room. This calculator uses the standard 25 BTU/h per square foot and then adds a flat 4,000 BTU/h for appliances, which is the long-standing allowance in HVAC sizing guidance. An oven at temperature, a hob with two rings going and a fridge compressor cycling all add heat regardless of whether the kitchen is small or large, and a small kitchen with a full cooking load can genuinely need more capacity than a larger room with none. The flat allowance is why a galley kitchen and an open plan kitchen of twice the area do not differ by a factor of two. Extraction changes the picture more than any other single factor: a properly ducted extractor removes both heat and moisture at source, whereas a recirculating hood filters grease and returns the heat straight back into the room. If your kitchen opens into a living space, measure the whole connected area and see Living Room BTU Calculator.
How to use Kitchen BTU Calculator
- Enter room area in m² or ft²
- Set ceiling height, sunlight exposure, and number of occupants
- See recommended BTU, kW, and AC unit type
Frequently Asked Questions
- Why does a kitchen get a flat 4,000 BTU allowance?
- Because ovens, hobs and refrigeration produce heat independent of room size. A small kitchen with the oven on has nearly the same appliance load as a large one, so the allowance is added as a fixed figure rather than scaled by floor area.
- Does an extractor fan reduce the requirement?
- A ducted extractor that vents outside removes heat and moisture at source and makes a real difference. A recirculating hood only filters grease and returns the air, along with its heat, back into the room, so it does not reduce the cooling load.
- How many BTU for a small kitchen?
- A 100 square foot kitchen needs roughly 2,500 BTU/h for the space plus the 4,000 appliance allowance, so around 6,500 BTU/h in total. The appliance figure dominates in small kitchens, which is exactly why area alone is misleading.
- Should I include the fridge?
- It is already in the flat allowance. A fridge rejects heat into the room continuously through its condenser, which is why a kitchen never fully cools down overnight the way other rooms do.
- What about an open plan kitchen diner?
- Measure the whole connected area and add the appliance allowance once. Air moves freely between the zones, so the equipment has to condition all of it rather than just the part with the cooker in it.
Related Tools
Also Available As