EPCS | EXISTING HOTELS Are EPCs fit for existing hotel building stock? Legislation is forcing landowners to improve the performance of buildings based on energy performance certificates. REsustains Annie Marston compares the actual performance of hotels with their EPCs to understand the most effective improvements W ith the climate and energy emergencies high on everyones agenda and an uncertain winter ahead, our attitude to buildings and their energy usage has altered significantly over the past few years. We can no longer maintain a business-as-usual attitude to our existing building stock. With potentially crippling energy costs, it is important that these buildings work as efficiently as possible, and that all investments and efficiency recommendations are considered thoroughly and recognised. The majority of our existing commercial building stock runs poorly. The pandemic showed that empty buildings could not be turned off, and it highlighted the need to make them more flexible and efficient. In the UK, there is a legal obligation for commercial buildings to achieve various grades for their energy performance certificates (EPCs) in order to be rented. In the 2020 Energy White Paper, the UK government established the trajectory of the minimum energy efficiency standard of all non-domestic buildings to achieve an EPC B by 2030. This improvement is estimated to apply to 85% of the current non-domestic building stock. A summary of the current EPC requirement trajectory is shown in Figure 1. Should the buildings not reach these targets, they will no longer be able to be tenanted. With large investments readily agreed by building stock owners to meet environmental, social and governance goals it is important that this money is put into the building in the correct places. To understand this impact on the hotel sector, a study was completed on the effect of energy improvements on the hotel stock for both EPC ratings and actual energy and carbon improvements. This study looked at 120 hotels in a portfolio built since the 1980s. The National Calculation Methodology (NCM) is used to calculate the EPC rating for building types. It is based on benchmark data and is not supposed to reflect actual operation of the buildings. The NCM has set inputs that cannot be altered, such as domestic hot-water flowrates, occupancy and so on. (See panel, Set NCM inputs for the important details for the hotel type that cannot be changed from the NCM.) When the portfolio of hotels actual, metered electricity, gas and domestic hot-water use was assessed and compared against these benchmarks, it showed clearly that the EPC benchmarks were overestimating domestic hot-water usage by 5-10 times their actual usage which, from the metered data, we worked out to be approximately 30 litres per day on average. 54 October 2022 www.cibsejournal.com CIBSE Oct 22 pp54-56 Hotel EPCs Supp.indd 54 26/09/2022 16:11