The higher the temperature, the shorter the drying time. An extra source of heating should be used when drying buildings. This is vital when the temperature is circa 10ºC, as the air cannot contain any moisture as these temperatures.

Expert tip: When dehumidifiers are used in conjunction with heaters, don’t locate them too close to each other or the dehumidifier will only suck up the heated air and no dehumidification will occur.

Heat Performance Calculation

The following formula can be used to make an estimation of the heating performance for rooms approx. 1000m³

Room volume m³ x K-VALUE x desired temperature difference = required KCAL

Where K-VALUES are as follows:

  • New building (good insulation): 1.2K-VALUE
  • Average insulation: 2.2K-VALUE
  • Bad insulation (old house): 3.0K-VALUE
  • No insulation (marquee): 4.0K-VALUE

To convert KCAL into Watts, use the following formula: measured KCAL x 1.16 = Watt


  • Complete house 140m², height 2.7m, windows installed.
  • Volume = 378m³
  • Insulation / K-VALUE: 2.0
  • External minimum temperature approx. = -2ºC
  • Desired room temperature = 12ºC
  • Temperature difference = 14ºC

CALCULATION: 378x2x14x1.16 = 12,277Watts = 12.2kw