Related services Daylight reflectanceThe requirements on daylight reflectance by BCA are available in this circular dated 27/06/2016. Please refer to Section P.3.2 of the document (pages 5-6) for the requirements.
Below is a flowchart prepared by us for your easy reference:
For a specific scenario, you may click one of the blocks below for more elaborations.
My material is glass
For glasses, the requirement is that the daylight reflectance shall be less than 20%.
Please note the following:
- For glasses, the concept of total/diffuse/specular daylight reflectance is not applicable, as glass is a material with specular reflection only (without diffuse reflection).
- Daylight reflectance is also called visible light reflectance in some contexts. The “visible light reflectance, front” result in our glass test report is the same as the daylight reflectance result.
My material is not glass and is installed on a facade or horizontal/low-slope roof
For non-glass materials installed on facades or horizontal/low-slope roofs, the requirement is that the specular daylight reflectance shall be less than 10%.
Please note the following:
- Specular daylight reflectance is also called specular reflectance in some contexts. They are the same.
- Low-slope roof refers to a roof with less than 20 degrees of inclination angle (a horizontal roof is with 0 degrees of inclination angle).
My material is not glass and is installed on a steep-slope roof
For non-glass materials installed on steep-slope roofs, the requirement is that the total daylight reflectance shall be less than 20%.
Please note the following:
- Total daylight reflectance is also called daylight reflectance in some contexts. They are the same.
- Steep-slope roof refers to a roof with greater than 20 degrees of inclination angle (a horizontal roof is with 0 degrees of inclination angle).
