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

R24-27C O N L I N E V E R S I O N Section 2: Calculating the building primary energy rate and building emission rate 2.1 The same approved calculation tool must be used to calculate the target primary energy rate, the target emission rate, the building primary energy rate and the building emission rate. 2.2 The building primary energy rate and the building emission rate must be calculated at both of the following points using the same calculation tool. a. Before work starts, using design values. b. When work is complete, using figures for the building as constructed, and incorporating both of the following. i. Any changes that have been made during construction to the list of specifications. ii. The measured air permeability. 2.3 At both of these points the building primary energy rate and building emission rate must not exceed the target primary energy rate and the target emission rate, respectively. The specification of the actual building may vary from that of the notional building if the building meets the target primary energy rate, target emission rate and the guidance in this approved document. Building control notification 2.4 The building control body must be notified, before the work starts, of all of the following. a. The target primary energy rate and the building primary energy rate (calculated using design values). b. The target emission rate and the building emission rate (calculated using design values). c. A list of specifications used in the calculations. Items (a) to (c) above may be reported using the design stage Building Regulations UK Part L compliance report (BRUKL report) which is produced as a standardised output from the approved software. For further details of the design stage BRUKL report, see Appendix C. 2.5 The building control body must be notified, once the work is complete, of all of the following. a. The as-built target primary energy rate and as-built building primary energy rate. b. The as-built target emission rate and the as-built building emission rate. c. A list of specifications used in the as-built calculations, and whether the specifications have changed from those used in the design stage calculations. Building control bodies are authorised to accept notification of (a) to (c) above as reported in the as-built BRUKL report, which is produced as a standardised output from the approved software. For further details of the as-built BRUKL report, see Appendix C. 10 Approved Document L Volume 2, 2021 edition Building Regulations 2010 O N L I N E V E R S I O N