BASIX assesses energy saved by direct natural lighting based on:
- whether windows or skylights will be installed in the kitchen; and
- how many separate bathrooms or toilets will be naturally lit by either a window or a skylight.
Direct natural lighting means that the light source can be either a window or skylight. The window must be part of the perimeter wall of the room being lit. The skylight must be located in the roof of the room to be lit.
Bathrooms and toilets must be separate, fully enclosed rooms, enclosed by their own wall or wall/door combination. For example, if a toilet is located inside a bathroom, it cannot be counted twice.