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

O N L I N E V E R S I O N AD Table D1 E nergy efficiency measures which should usually be installed whenever consequential improvements are required These measures are considered technically, functionally and economically feasible in normal circumstances. These measures should be installed at least to the extent outlined to meet the reasonable provision criterion, based on the value of the principal works, as outlined in Section 12. Item Improvement measure 1 Upgrading heating systems that are more than 15 years old by providing new plant or improved controls. 2 Upgrading cooling systems that are more than 15 years old by providing new plant or improved controls. 3 Upgrading air-handling systems that are more than 15 years old by providing new plant or improved controls. 4 Upgrading general lighting systems that have an average lamp efficacy of less than 60 light source lumens per circuit-watt and that serve areas greater than 100m2 by providing new luminaires and/or controls following the guidance in Section 6. 5 Installing energy metering following the guidance given in CIBSE’s TM39. 6 Upgrading thermal elements that have U-values higher than those in Table 4.2, column (a), following the guidance in paragraphs 4.7 and 4.8. 7 Replacing existing windows, roof windows or rooflights (but excluding display windows) or doors (but excluding high-usage entrance doors) that have a U-value higher than the following. a. For windows, roof windows and doors – 3.30W/(m2·K) b. For rooflights – 3.80W/(m2·K), calculated by following paragraph 4.4. 8 If existing on-site low and zero carbon energy-generating systems provide less than 10% of on-site energy demand: increasing the capacity of on-site systems, provided the increase will achieve a simple payback of 7 years or less. 9 Measures specified in the recommendations report that accompanies a valid energy performance certificate which will achieve a simple payback of 15 years or less. NOTE: Items 1 to 7 usually meet the economic feasibility criterion of a simple payback of 15 years. A shorter simple payback period of 7 years is given for item 8 because such measures are likely to be more capital intensive or more risky than the others. Additional measures usually to be installed when consequential improvements are required following changes to fixed building service provision D5 When consequential improvements apply as a result of providing a fixed building service in the building for the first time or increasing the capacity of an existing fixed building service, additional energy efficiency improvements to those parts of the building served by the service should be made. The extent of these measures should not be based on the value of the principal works, as outlined in Section 12. All technically, functionally and economically feasible measures to improve the parts of the building served by the service to meet the requirements of Part L should be implemented. D6 The measures in Table D2 improve the energy efficiency of those parts of the building served by the service, and can be considered technically, functionally and economically feasible in normal circumstances whenever these additional measures are required. 9955 BBuuiillddiinngg RReegguullaattiioonnss 22001100 AApppprroovveedd DDooccuummeenntt LL VVoolluummee 22,, 22002211 eeddiittiioonn O N L I N E V E R S I O N