Daylight Reflectance Design Guide

Singapore's Daylight Reflectance Design Guide was jointly prepared by the Building and Construction Authority (BCA) and the National University of Singapore (NUS) to improve understanding of daylight reflectance from buildings. The first edition was published on 1 September 2022 and is aimed primarily at building designers, while also being relevant to developers, facility managers and others involved in design decisions (BCA and NUS Daylight Reflectance Design Guide, accessed 2 September 2026).

Reflected glare in Singapore's built environment

Reflected sunlight from a building façade can create glare in Singapore's strong solar-radiation conditions and dense urban environment. The guide explains that increasingly diverse building forms and reflective materials such as glass and metal cladding make façade reflectance a design issue alongside architectural appearance. Appropriate planning and design can improve visual performance and reduce incidences of reflected glare affecting neighbouring buildings (BCA and NUS Daylight Reflectance Design Guide, accessed 2 September 2026).

Factors beyond a single reflectance value

The guide distinguishes the total reflectance value of the building envelope from other parameters that contribute to solar reflectance and glare. It recommends considering those factors from the urban-planning and building-design perspective at the onset of design, including the site and building parameters that influence how sunlight is reflected toward surrounding locations (BCA and NUS Daylight Reflectance Design Guide, accessed 2 September 2026). The guide is therefore about managing the interaction of façade, sun and context, not simply selecting a material by colour or appearance.

Site assessment and simulation

The Daylight Reflectance Design Guide recommends a set of considerations for assessing site and building parameters and identifying mitigation measures to minimise reflected-glare occurrences. It also includes an example of using computer simulation for solar-glare evaluation, allowing a design team to assess whether a proposed building may cause significant glare to neighbouring buildings (BCA and NUS Daylight Reflectance Design Guide, accessed 2 September 2026). A simulation example is an assessment method in the guide; it is not a published guarantee that every project using the method will receive approval or avoid all glare.

Relationship to mandatory requirements

The guide is not a substitute for compliance with the Building Control Regulations or the maximum allowable reflectance value for façade material prescribed in the Approved Document. BCA and NUS present it as design information and recommendations to support decisions beyond that mandatory boundary (BCA and NUS Daylight Reflectance Design Guide, accessed 2 September 2026). Following a recommendation in the guide does not by itself establish compliance, planning approval or a universal safe reflectance level for every façade and site.