For a shell only assessment, only the EPR demand metric is used to determine the energy performance. Therefore, we would not expect to see improvements to equipment and services accounted for in the BRUKL/NCM calculation. It is, therefore, recommended that assessors submit a BRUKL/NCM document incorporating the fabric improvements, but which retains the equipment and services of the notional building with heating and cooling provided by multi-split systems.
Credits for shell only assessments are determined by the demand metric alone. The inclusion of more efficient equipment and services may, therefore, lead to lower heat gains, a subsequent increase in demand for space heating and, hence, a lower number of credits being awarded.
28 Aug 2022 - Guidance updated and applied to UKNC V6