The heating load is the amount of heat energy that would need to be added to a space to maintain the temperature in an acceptable range.
The cooling load is the amount of heat energy that would need to be removed from a space (cooling) to maintain the temperature in an acceptable range.
The heating and cooling loads, or "thermal loads", take into account:
- the dwelling's construction and insulation; including floors, walls, ceilings and roof; and
- the dwelling's glazing and skylights; based on size, performance, shading and overshadowing.
Lower thermal loads indicate that, relatively, the dwelling will require less heating and cooling to maintain comfortable conditions. Lower thermal loads do not necessarily correspond to lower electricity usage.
In practice, the heating and cooling loads may be handled by heating or air-conditioning equipment. The efficiency of the equipment and the fuel type is assessed in the Energy section of BASIX. Lower loads will improve your Energy score.
Maximum heating and cooling loads
The maximum heating and cooling loads for the dwelling are calculated by BASIX based on the climate zone.
BASIX Thermal Performance sets maximum heating loads and cooling loads separately, meaning that good performance in heating or cooling alone will not be undermined by poor performance in the other.
BASIX Thermal Performance also sets the maximum total loads for certain building types in some climate zones. The total load is the sum of heating and cooling loads.