Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings·Page 27·2.26
Conservatories without thermal separation
Conservatories or similar highly glazed spaces without thermal separation from the rest of the building must be regarded as integral parts and included in TER, BER, and air pressure test calculations.
Where a new building incorporates a conservatory or similar highly glazed space which does not have thermal separation from the rest of the building it should be regarded as an integral part of the building and be included in the calculation of the TER and BER and in the air pressure test.
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