Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings·Page 10·42
Regulation 42 - Change of energy status
When a building undergoes a change of energy status, necessary work must be carried out to ensure the building complies with conservation requirements.
Where there is a change of energy status such work shall be carried out as is necessary to ensure that the building complies with the requirements of regulation 39.
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