Modern Building Services

14 MODERN BUILDING SERVICES JULY 2022 FEATURE INDOOR AIR QUALITY N ew buildings across the UK are being built and designed for greater efficiency, sustainability, and decarbonisation in line with the industry-wide net-zero approach – and that is a great success story for the 20%of buildings and homes still planned for 2050. However, when looking at efficiency and how wemake our existing stock greener, the focus and energy seems to decline as puzzled faces debate the best approach. Older working buildings pose their own complex efficiency issues, from overheating to ventilation effectiveness and heat retention. Often built against old building regulations, the refurbishment and refit of these buildings must become a focus for 2050 as much as new stock – as an industry, the focus needs to be on making them better if we hope to drive better returns for both people’s pockets and the planet. The main question we face is how we do it. In terms of ventilation and air movement, we see buildings suffer under years of change, with problems being tackled piecemeal – from desk moves in an office to tackling solar gain for buildings with south-facing facades - but never completely overhauled to make a difference in the building in its entirety. Overheating problems Overheating is one of these major issues and one that is causing the industry great concern. In our efforts to create more energy- efficient buildings and make our existing buildings less leaky – the more we are making buildings ‘airtight’, through triple glazing and insulation. This, in turn, creates ‘heat boxes’, which raise another set of problems to solve. There are many contributing factors to overheating: climate change spiking summer-time temperatures, architectural glass design demands, buildings being built ‘too tight’ and the requirement for high-rise builds due to inner-city conurbations with limited space. Not only does overheating have amajor impact on whether the property is occupiable, in some cases making it uninhabitable in the summer months, but it can also cause serious problems with lethargy, heat stress, and other major health risks. At its worst, it can result in premature death. Addressing the issue from the inhabitant’s point of view is something the industrymust start to do – it isn’t enough to use air conditioning to cool the roomwhile circulating stale, dirty indoor air. These buildings need cooled, filtered air to ensure occupant wellbeing. The METOffice has documented that the number of ‘extremely hot days’ could increase fourfold from 10 to 37 percent if global temperatures rise by just 7.2°F – adding alarming concern to the issues overheating causes. CIBSE has also advised that if the issue is not addressed, 4500 premature deaths per year are expected by 2050 1 . In addition to this, experts claim that the global temperature is likely to rise 1.5 degrees above pre-industrial levels by 2051 and heatwaves will increase in frequency making this an issue that won’t go away and should not be ignored. It is known that 4.6m homes in England are already reported to have overheating problems, with more new builds being built set to face these same issues. Stuart Smith , Group Sales Director and indoor air quality specialist at ventilation manufacturer Nuaire, discusses the modern-day concerns on indoor air quality and overheating. How the industry can help buildings last by performing more efficiently