Technical Booklet F1 Conservation of Fuel and Power in Dwellings·Page 44·3.30
Performance standards for previously exempt conservatories and porches with changed energy status
When a conservatory or porch is no longer exempt, it must have controlled fittings no worse than Table 3.1, thermal elements no greater than Table 3.2, and independent temperature and on/off controls if heated or cooled. Non-compliant elements must be replaced, upgraded, or compensated for.
In such cases, the previously exempt conservatory or porch should have – (a) controlled fittings whose performance is no worse than that given in Table 3.1; (b) thermal elements that have U-values no greater than that given in Table 3.2; and (c) where the conservatory or porch is heated or cooled, independent temperature and on/off controls. Where any of the above does not meet these standards it should be replaced or upgraded. Alternatively compensating provisions should be made in accordance with Equivalent Carbon Target Approach in paragraph 3.28.
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