1. Room size:
What’s the length, width and ceiling height? While floor space is important, so is total volume – a room with high ceilings will require more energy to cool.
Are the ceilings and walls insulated? What’s underneath and on top of the room? Ceiling insulation is one of the biggest factors in making your home thermally efficient.
Room in Durban will need a more powerful air conditioner for cooling, compared to an otherwise identical room in Pietermaritzburg.
Which way does the room face? A large north- or west-facing window can let in a lot of heat in summer, whereas a shaded, southern-facing window will be cooler.