This document provides a design process for daylight openings in order to ensure the principle of sustainability in the indoor visual environment. The design process for daylight openings includes the consideration of:

— sunshine duration in the building interiors;

— daylight opening ratio to the wall area of a habitable room;

— daylight opening ratio to the floor area of a habitable room;

— appropriate levels of indoor daylight based on human visual needs and the extent of sunlight;

— daylight control systems in the building;

— thermal comfort, thermal gains and energy efficiency.

This document is applicable to building environment design for new buildings and the retrofit of existing buildings.