Conditioned space

for the purposes of Volume One, means a space within a building, including a ceiling or under-floor supply air plenum or return air plenum, where the environment is likely, by the intended use of the space, to have its temperature controlled by air-conditioning .

for the purposes of Volume Two, means a space within a building that is heated or cooled by the building’s domestic services , excluding a non- habitable room in which a heater with a capacity of not more than 1.2 kW or 4.3 MJ/hour is installed.

volume of a space to which treated air is supplied