"For a highly glazed part of the dwelling, such as a sun room, which does not meet the criteria for a conservatory (50% of walls and 75% of roof glazed), in most cases use the glazing option of “more than typical”. That adds 25% to the total glazed area of the dwelling. If you deem that this is not appropriate, assess window area by either: a) measuring all windows and roof windows throughout the dwelling, or b) measuring all windows and roof windows in the sun room, and use Table S4 to obtain the window area of remaining part of dwelling which is entered as a single window. Record method used in site notes."