Technical Booklet F2 Conservation of Fuel and Power in Buildings Other Than Dwellings·Page 14·0.5
Renovation of thermal elements - major renovation or 50% surface area
When renovation or replacement work to a thermal element constitutes a major renovation or covers more than 50% of the element's surface, the requirement to limit heat gains and losses under regulation 39(a)(i) must be met.
It is the view of the Department that when renovation and/or replacement work to an individual thermal element constitutes a major renovation or the renovation amounts to more than 50% of the surface of the element, the requirements of regulation 43 will be met when work is undertaken to limit heat gains and losses as required by regulation 39(a)(i). Renovation of a thermal element does not include a partial replacement layer provided solely as a means of patch repair to a flat roof and does not include thin decorative surface finishes.
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