Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings·Page 58·3.57
Definition of controlled fitting
A controlled fitting for windows, roof windows, rooflights or doors means the complete unit including the frame; replacement of a single broken pane is not considered a controlled fitting.
The term "controlled fitting" in relation to a window, roof window, rooflight or door means the unit as a whole (i.e. it includes the frame). Consequently, the replacement of a broken window pane is not the provision of a controlled fitting.
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