Use this calculator to find out what capacity heater you need, based on the type and size of area you need to heat.

kW BTU
Oil/Gas 0 0
Electric 0 0

## Buildings and Halls

For the decision of which kind of heater and the required heat capacity, the type and size of the room that needs to be heated are decisive. The following general rules give you guides for the often required quick decisions - unless you have a heat requirement calculation from an architect at hand this one should be preferred. For buildings and halls a general rule assumes a maximum temperature rise (difference between the lowest anticipated outdoor temperature and the highest inside temperature) of 30°C. For other temperature rises you have to reduce or increase the heat capacity by 17 % for every 5°C.

### Non-redeveloped rooms in old buildings or shells before installation of insulation

Oil or Gas heaters: Volume (m³) x Factor 0.058 = Req. heat capacity (kW)

Electric heaters: Volume (m³) x Factor 0.041 = Req. heat capacity (kW)

### Old buildings with average insulation

Oil or Gas heaters: Volume (m³) x Factor 0.040 = Req. heat capacity (kW)

Electric heaters: Volume (m³) x Factor 0.030 = Req. heat capacity (kW)

### New buildings with insulation

Oil or Gas heaters: Volume (m³) x Factor 0.025 = Req. heat capacity (kW)

Electric heaters: Volume (m³) x Factor 0.020 = Req. heat capacity (kW)

## Green houses and tents

For the calculation of the required heat capacity of green houses and tents, different to buildings and halls, the entire outer surface should serve as the base for the calculation instead of the room volume. This is simply because the heat loss of such constructions is proportional to the outer surfaces.

### Green houses and tents without insulation

Oil or Gas heaters: Outer surface (m²) x Factor 0.0064 x Temp. rise = Req. heat capacity (kW)

### Green houses with double glassing and thermo tents

Oil or Gas heaters: Outer surface (m²) x Factor 0.0037 x Temp. rise = Req. heat capacity (kW)