Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings·Page 54·3.36
Glazing Area Limits for Material Change of Use
When a building undergoes material change of use with glazing exceeding 25% of total floor area, the glazing must either be reduced or compensated for using an equivalent carbon target approach.
In a building subject to a material change of use, where the area of glazing is more than 25% of the total floor area of the building, either the area of glazing should be reduced to no greater than 25%, or the larger area should be compensated for using the procedure described in paragraph 3.38.
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