The National Construction Code (NCC) sets the minimum requirements for natural lighting in NCC Vol 1.0 Part F4, which states that “Sufficient openings must be provided and distributed in a building, appropriate to the function or use of that part of the building so that natural light, when available, provides an average daylight factor of not less than 2.”

This provision applies to the following building classes:

• Class 2 buildings and Class 4 parts of buildings — to all habitable rooms
• Class 3 buildings — to all bedrooms and dormitories
• Class 9a and 9c buildings — to all rooms used for sleeping purposes
• Class 9b buildings — to all general purpose classrooms in primary or secondary schools and all playrooms or the like for children’s use in an early childhood centre

Local councils in Victoria may also have additional requirements for daylighting, so it’s important to meet the provisions of your governing council and the NCC.

The Daylight Assessment is a major contributor to most of your score for IEQ in the BESS tool. Because the proposed building must achieve a mandatory pass minimum score of 50% for Indoor Environment Quality (IEQ), it is important to prioritise daylighting in your ESD plans.