SPONSORED ROUNDTABLE | VENTILATION STRATEGIES CIBSE Journal editor Alex Smith (centre), with (from left) Dr Liora Malki-Epshtein; Ted Pilbeam, Hern Yau, James Morris, Alasdair Donn and Neil Pennell VENTILATING FOR NET ZERO In the post-pandemic environment, balancing effective ventilation and energy efficiency is a prime challenge for engineers. At the latest CIBSE Journal roundtable, industry experts aired their opinions on how best to optimise design to achieve comfort and net zero carbon building emissions. Amanda Birch reports A s the UK sweltered in Julys record-breaking heatwave, it was an appropriate time to discuss the challenges of ventilating buildings in a post-pandemic world. At a CIBSE Journal roundtable, sponsored by Mitsubishi Electric, contractors, consultants, housebuilders and academics discussed how energy efficient, effective ventilation strategies could be achieved. The participants looked at the impact of the recent changes to the Building Regulations, covering energy performance (Part L), ventilation (Part F) and overheating (the new Part O). They also explored how designs are changing to comply with the Future Homes Standard regulations on the path to net zero 2025. Those around the table all agreed that the recent changes to the regulations were not far-reaching enough and that many in the industry were already working towards more ambitious targets. Part L hasnt pushed far enough in the right direction, said Alasdair Donn, head of building performance at Willmott Dixon. The fear of introducing regulations that make MVHR [mechanical ventilation with heat recovery], particularly in homes, the right thing to do is a shame. The better solution would be to incentivise MVHR and make sure its applied in a good, high-quality way. James Morris, project principal at Mott MacDonald, agreed that the regulations could have gone further to reward people who apply MVHR systems in buildings. He added that there was a disconnect between Part L and Part F. Part L asks for airtight buildings, while Part F asks for windows to have trickle vents. Morris suggested that the next step in the regulations should be to close this loophole and promote the heatrecovery route, which should provide continuous fresh air in winter and reduce heat loss. Being cognisant of the Building Regulations is a given, said Neil Pennell, head of design, innovation, and property solutions at Landsec. We set our own targets with regards to positioning ourselves, as a business, to be net zero carbon by 2030, he said. Thats challenging us to think beyond the Building Regulations and how we assess the designs of our buildings going forward. For Landsec, Pennell added, it was more of a priority to improve the performance of existing properties. We have established a fund of 135m to reinvest into that existing property portfolio, to help it move towards meeting the 38 September 2022 www.cibsejournal.com CIBSE Sept 22 pp38-40, 42 Mits Electric Roundtable.indd 38 26/08/2022 18:33