By Alex Green, Programme Manager (Awards and Schools)
When it comes to tomorrow’s school buildings, the concept of ‘passive design’ could help lower bills and fight the climate crisis while keeping staff and students happy and comfortable
Poor energy efficiency in school buildings does more than frustrate staff and students – it can drive up bills by tens of thousands of pounds. There are many quick and easy ways for schools to save energy – but if their buildings are draughty, energy-hungry or poorly designed, cutting costs will always be an uphill struggle. The need to lower energy use is also fuelled by the growing climate emergency.
There are a host of tools and approaches to help schools tackle energy use – from student energy clubs to smart software that pinpoints key causes of energy waste. But when it comes to tomorrow’s school buildings, the concept of ‘passive design’ could help lower bills and fight the climate crisis while keeping staff and students happy and comfortable.
What is passive design?
Passive design maximises the use of natural sources of heating, cooling and ventilation to create comfortable conditions inside buildings. It harnesses environmental conditions such as solar radiation and cool night air to control the indoor environment – cutting the need for gas and electricity.
Passive design is on the rise, driven by society’s growing interest in sustainability. A passive design project in Norwich won the 2019 Stirling Prize, the UK’s most prestigious architecture award. The award-winning project is a social housing development – proving that this approach isn’t just for high-end homes or offices. And the concept has already had an impact at schools in the UK and beyond.
St Luke’s School has passive design at its heart. The Wolverhampton primary won its designer, architecture firm Architype, an Ashden Award for sustainable buildings. Passive measures used at St Luke’s and elsewhere include efficient insulation and orienting the building so large windows face south, allowing winter sunlight to penetrate the building and bring extra heat. To tackle the problem of summer overheating, carefully located north-facing windows allow extra light in without driving up temperatures. The building fabric is air-tight to eliminate draughts, with controlled ventilation through specially designed vents.
St Faith’s Prep School in Cambridge used a passive design for a new building completed in just seven weeks. The building features a timber frame with compressed newspaper for insulation, and a green roof with plant growth to help insulate the building. The roof also collects rainwater to top up a nearby pond. Energy use is even lower than the school predicted.
Passive design can be a greater or smaller feature of any building project. Passivhaus, a globally-recognised passive design standard, calls for thorough use of passive design throughout the building – and as a result can deliver huge energy savings. But this standard can involve a larger initial cost, and many passive ideas can easily be introduced into more mainstream building designs.
One piece of the puzzle
Even though they generate savings, many passive design features currently bring a slightly higher up-front financial cost than less sustainable alternatives – although growth in passive design should bring prices down.
The spread of this concept into schools will rely on governments taking a more long-term approach to education funding (and showing a genuine ambition to take on the climate crisis). But it could be one way the UK meets its target of net-zero carbon emissions by 2050, while also inspiring future generations with examples of sustainability in action.
Realistically, the UK Government will need a wide package of measures to address the climate impact of school buildings – including retrofitting older buildings, as well as higher standards for those yet to be built. So passive design will only ever be one tool in our efforts to address a complex challenge.
Experts in passive design are often used to boost sustainability in other ways – for example by using locally sourced materials, or lower-impact ones such as sustainable timber. These steps are crucial because day-to-day energy use is just one part of a building’s carbon footprint. In fact, the World Green Building Council has said that embodied carbon – emissions purely related to construction, rather than building use – makes up 11 per cent of the global emissions total.
Clean energy unites communities
Schools can also go green and save money by generating electricity themselves. There are organisations across the country helping them do this – Oxfordshire’s Low Carbon Hub has helped communities install solar panels on 10 per cent of the county’s schools. Schemes it supports lower energy bills by an average of 28 per cent. Repowering, another social enterprise, helps disadvantaged communities in London harness the benefits of renewable energy. As well as supporting schools, it has given young people training and skills for the future – showing how investing in sustainability brings a huge range of benefits.
Finally, cutting energy use is at the heart of Ashden’s LESSCO2 programme. This programme helps schools share advice and best practice, and has already lowered bills in hundreds of schools across the UK. The programme relies on harnessing the enthusiasm of staff and students, who are often keen to see their school become more sustainable. So as well as protecting budgets, greener school buildings can encourage the actions and attitude changes, both at school and at home, that we need to create a brighter future.
This piece first appeared in Education Business