This document specifies a method to measure the solar heat gain coefficient for the centre of glazing in fenestration systems (e.g. complete windows, doors or curtain walls with or without shading devices) for normal and off-normal irradiation on the surface.

This document applies to the centre of glazing in fenestration systems which might consist of:

a) various types of glazing (e.g. glass or plastic; single or multiple glazing; with or without low emissivity coatings, and with spaces filled with air or other gases; opaque or transparent glazing);

b) various types of shading devices (e.g. blind, screen, film or any attachment with shading effects);

c) various types of active solar fenestration systems [e.g. building-integrated PV systems (BIPV) or building-integrated solar thermal collectors (BIST)].

This document does not include:

a) shading effects of building elements (e.g. eaves, sleeve wall, etc.);

b) shading effects of fenestration attachments with overhang structures (e.g., awning, etc.) or similar;

c) shading effects of non-glazing elements in fenestration systems (e.g. window frame, etc.);

d) heat transfer caused by air leakage between indoors and outdoors;

e) ventilation of air spaces in double and coupled windows;

f) thermal bridge effects at the joint between the glazing and the rest of the fenestration parts (e.g. window frame, etc.).