Modern Building Services

16 MODERN BUILDING SERVICES JUNE 2021 FEATURE VERTICAL FOCUS SCHOOLS AND HOSPITALS VERTICAL FOCUS T he UK government recently announced that it will introduce a more ambitious target to reduce emissions by 78%by 2035, compared to 1990 levels, as part of a new Sixth Carbon Budget. As this will require the near total decarbonisation of heat in buildings, the building services industry has a critical role to play in achieving this goal. Setting the UK’s ‘hard-to-tackle’ existing building stock on the road to net zero is a tough but urgent challenge. The need for action is particularly pressing in the education sector which has a high proportion of ageing buildings – many with heating systems that have seen better days. Recognising this, the government has introduced a ten- year rebuilding programme and included schools within the Public Sector Decarbonisation Scheme to install energy efficiency and low carbon heating measures. Heating manufacturers are supporting the move to the future of heat with innovative technologies and techniques, including hydrogen boilers, heat pumps and equipment to support the delivery of heat networks. However, schools embarking on a heating refurbishment programme often face a range of obstacles that make use of some alternative technologies very difficult. So, how can manufacturers and building services professionals help schools to bring these hard- to-treat buildings – and their heating systems – up to code? Design challenges First let’s consider the design issues on schools heating refurbishment projects. Some schoolsmay be dealingwith the cast iron radiators and poorly-fittingwindows of a Victorian primary school. Others will be contendingwith poor insulation or overheating from large glazed areas in themoremodern, but equally problematic, secondary school buildings of the 1960s and 1970s. In both building types, tight budgets unfortunatelymean that maintenance of heating systems can be neglected for extended periods – even until failure. Indeed, some 57%of England’s schools have faulty boilers or heaters, according to the Times Educational Supplement (TES). This can then cause problems with hydronics and uneven heating output, resulting in classrooms that are either too hot or too cold. Phased approach For many schools, switching from dated non-condensing boilers to low carbon technologies in one leap simply won’t be a technically or economically viable option at present. But if we are to achieve our climate goals, it’s vital to seize every opportunity to improve heating and hot water efficiencies in our existing schools. Apractical solution is toadopt a phasedapproach thatwill enable schoolstoplanandbudgetadequately tomeet their long-termneeds. In poorly insulated buildings, energy efficiency measures should be the first step to reduce heat losses and lower heat demand. Addressing the system’s distribution pipework and heat emitters to operate at lower temperatures than the traditional 82°C/71°C systemdesigns is the next stage. This will future proof the building and the heating system for the integration of lower temperature, low carbon technologies. And in the immediate term, replacing any old heating plant withmodern energy-efficient gas boilers offers a cost-effective and timelymeans of achieving emissions reduction from this part of the public building stock. Taking steps like this nowwill save emissions sooner – and provide a ready solution for schools that face inadequate heating and hot water provision. Holistic system thinking Given the age of the buildings, careful planning is central to success. The boiler is the heart of the system, generating the heat, and as such can have the most impact on energy and emission savings. But finding a convenient time to carry out even a relatively straightforward boiler replacement can be challenging, given that work is typically carried out during the fixed periods of school shutdown. Budget is a significant factor for schools, so it’s critical to identify the solutions that offer the most beneficial impact within budget while meeting their short- and long-term outcomes. UK schools are ageing, and their heating systems have seen better days, says Andy Green , Technical Director at Baxi Heating. Taking immediate action to refurbish them is vital to put these ‘hard-to-tackle’ educational buildings on the road to the future of heating Setting schools on the path to net zero