Conservation of fuel and power: Approved Document L, Volume 2 — Buildings other than dwellings

D O N L I N E V E R S I O N Appendix D: Measures for consequential improvements D1 For an existing building with a total useful floor area of over 1000m2, additional work may be required to improve the overall energy efficiency of the building if proposed work consists of or includes any of the following. a. An extension. b. Providing any fixed building service in the building for the first time. c. Increasing the capacity of any fixed building service (which does not include doing so on account of renewable technology). D2 Additional works to improve energy efficiency as required in these circumstances are known as consequential improvements and are described in detail in Section 12. Measures usually to be installed whenever consequential improvements are required D3 Energy efficiency improvements to the building are required whenever consequential improvements apply. All technically, functionally and economically feasible measures should be implemented, with the requirement for consequential improvements being met based on the value of the principal works in some circumstances. This is outlined in Section 12. D4 The energy efficiency improvements in Table D1 can be considered technically, functionally and economically feasible in normal circumstances. As such, these measures should usually be installed when consequential improvements are required. These should be installed at least to the extent outlined in Table D1, based on the value of the principal works, as outlined in Section 12. 94 Approved Document L Volume 2, 2021 edition Building Regulations 2010 O N L I N E V E R S I O N