According to Professor Susan Roaf, the challenge to cut carbon dioxide emissions should start at home, with better architecture and engineering. Our 'zero-carbon' buildings should be able to withstand extreme weather conditions – functional and eco-friendly rather than just 'works of art'. Roaf believes that during the fossil fuel age, we began to rely on machines to make our buildings comfortable, but as oil and gas become more expensive, 21st Century buildings will have to de-mechanise, becoming more like…
Article by Peter Barr
Home is where the heart is – and the biggest source of greenhouse gasses on the planet. According to Professor Susan Roaf, Professor of Architectural Engineering at Heriot-Watt University, the built environment generates roughly 50 per cent of all carbon dioxide emissions in industrialised countries, and homes are responsible for about half of that figure. Studies have shown that for about £25 billion, every home in Scotland could be upgraded to reduce demand for energy, and thus reduce carbon dioxide emissions by more than 60 per cent. About half of that improvement would come from reducing demand through the actual design of the form and fabric of the house. More efficient white goods, electronic equipment and lighting would reduce emissions by a further 25 per cent, and that in turn could be halved by reducing the “carbon intensity of the supply” (i.e. using renewable energy). Adding all this together would reduce the average emissions of new builds by 75 per cent and refurbished properties by 60 per cent.
By investing an estimated £2 billion a year for 10 years, Scotland could thus reduce its total emissions by 20-30 per cent. “This would provide a massive stimulus for local industry and all but eliminate fuel poverty in Scotland,” says Roaf. It could also go a long way to meeting Scotland’s national emission reductions targets of 42 per cent by 2020, and even though £25 billion may seem a lot of money, Roaf points out that RBS was planning to pay £1.3 billion in bonuses this year. (A full discussion of the related social challenges is included in the concluding chapter of her recent book Adapting Buildings and Cities for Climate Change.)
“We already have the technology to put the solutions in place,” says Roaf. It’s the political will that we lack, she continues, because the fundamental values that we hold as a society are the same values holding us back from doing ‘the right thing’.
The challenge of making a building more sustainable is complex and involves the whole process of planning, siting, designing, constructing and running the building. The actual technology needed to create much greener 'zero-carbon' homes may prove to be as simple as getting the right insulation in place, double glazing, controlling air infiltration while using a range of natural ventilation techniques, combined with an understanding of heat flows through the building, solar gain, temperature, humidity, wind speed, thermal mass for energy storage and building fabric performance. And Roaf believes the first step is to get the basic architecture right – and that is why she's training a new generation of architectural engineers to do exactly that.
According to Roaf, there are many very difficult problems to overcome, including vested interests, social inertia and a lack of real vision among decisions makers. Roaf also thinks it is inevitable that developers promote inappropriate building solutions, because they think this means more profits. She then suggests: “Entrenched design professionals feel threatened by the trend towards rapid change. It is also understandable that anyone who can fill the vacuum can make lots of money, either posivitely through great new design or by promoting products that take us backwards – for example, whole-house mechanical ventilation systems in social housing. How can people who can't even pay for their cooking and lighting find the money to pay to have air pushed around in their homes? In a well-designed home, the sensible solution is simply to open the windows.”
Sustainable building solutions should take account of historic and social realities as well as technology, says Roaf. “Many developers also fail to realise that 'green' can mean opportunities to save build costs rather than requiring extra expense,” she continues. “A typical office with air-conditioning will pass through UK Building Regulations while the same office with natural ventilation may marginally fail, requiring it to install air-conditioning. Some developers and tenants actually prefer to boost their green credentials – and comfort – by not having air-cons, but are pushed into it by planners, building control officers and letting agents who think they can get higher rental values if the offices are fully air-conditioned. There are also many eco-minded, far-sighted clients, developers and architects, but they are sometimes held back by old-fashioned 20th century views – and 'fashionistas' who confuse modernity with shiny glass exteriors and see performance of the building as an afterthought. You can see the half-empty results around the world as occupants increasingly avoid the goldfish-bowl office blocks.”
Legislation should be ‘smarter’ and planners should encourage more sustainable designs, says Roaf. Most architectural students are interested in ecological issues, and they should receive better training, to understand the energy and environmental performance of buildings, so they can work with engineers to deliver better building solutions. Roaf also thinks it was a big mistake to privatise the UK's Building Research Establishment, “depriving us of a generation of the world's best blue skies thinkers about buildings,” and believes it is harder to win funds for pure research today – for example, if you want to analyse how buildings work in reality rather than simply using simulation.
Roaf's work at Heriot Watt is part of what the university's Energy Group sees as the 'Carbon Enlightenment' (see sidebar). She is involved in a wide range of issues related to the architecture and engineering of buildings, including everything from solar panels to thermal comfort, eco building and village design and carbon accounting for buildings. Originally trained as an architect, she is proud of the fact that her job title now includes the word 'engineering', not least because her father was an engineer from Heriot-Watt whose work took him all round the world, taking his family with him. From an early age, Roaf was aware of the importance of good engineering. Having grown up in Malaysia and Australia, she subsequently worked in Iran, doing research on ancient technologies and nomadic architecture. She also excavated in Iraq for seven years and worked in the Middle East as a landscape gardener, design consultant and lecturer at Baghdad University, and believes that this varied experience was an excellent preparation for 21st century design, in a world where the climate is changing. Roaf is also a pioneer in building-integrated photovoltaics, having built the UK's first integrated solar roof on her home in Oxford – the 'Ecohouse'.
“Architectural engineers nowadays have to have a much broader range of skills in the field of building performance,” she says. “They have to be everything from craftsmen to designers, scientists and technicians, learning many different aspects of design and construction as well as human behaviour.”
For instance, she explains, the more efficient buildings of the future should use their windows, walls and floors to collect, store and distribute the sun's heat in the winter and reject solar heat in the summer, maximising daylight for interior illumination. They should also optimise the potential for good natural ventilation systems.
In her drive to promote more sustainable buildings, Roaf also focuses on crucial political issues, including equality, social inclusion and the need for strong communities. “What's the use of having an ‘efficient’ and ‘profitable’ building sector if all the profits are taken abroad and none filter back down into the communities?” she asks. “What's the point if every time a roof is damaged you have to buy new sections from a faraway supplier? In Scotland, a high proportion of construction workers work locally, so where are the programmes to train them to be part of the local solutions to our 21st century problems? Many people want to improve the energy performance of their own homes, so where are the ‘One Stop Shops’ for information and building grants to help them apply those new building skills?”
Roaf also strongly believes that in order for our major cities to survive, we must make sure we don't create solutions for elites. “It's a matter of values,” she says. “If we are not a strong, joined-up society, then we have a very low chance of long-term survival.”
Underlining the human dimension of urban survival, Roaf also believes that “to reduce the exposure and the vulnerability of our populations to the growing economic, social and environmental hazards ahead will require all of us to act for the benefit of the greater good rather than the currently popular ethos of 'self-actualisation'. Roaf then admits this will be difficult and adds: “We need to re-order society in such a way that equality of opportunity and access to resources becomes a reality and the impacts of climate change are not disproportionately loaded onto one sector of society to the benefit of others. To date, climate change mitigation and adaptation strategies have seldom been associated with re-thinking the social, economic and physical infra-structures, but the recent carnage in the world’s markets may change this.”
Roaf also wants to see a systematic programme to retrofit the social housing stock in Scotland, starting with the 'fuel poor' – the 27 per cent of the population who spend more than 10 per cent of their income on fuel. “The situation will only get worse if energy prices continue to rise,” she says. “Where are the tried and tested, home-grown solutions, for Scotland's bungalows, tenements and tower blocks? They are there, but you have to look hard.”
Roaf believes the current “business-as-usual approach” must change, and says that the obsession with ‘efficiency’ alone has led to some very poor ‘green’ buildings. For example, solar energy is essential to Scotland and yet it has been strongly resisted in some very influential quarters. She also criticises eco-warriors and 'green' organisations who have not ventured into “the heart of the problems” in buildings. She says: “We have very high-profile political demonstrations against new airports and coal-fired power stations but not against energy- or water-profligate buildings like the glass towers of Dubai, Las Vegas or London. There is a plan for a new glass tower in Liverpool on top of a hill that will not only consume about as much energy as all the rest of the housing around it but also be very dangerous in extreme heat waves, storms and high winds. Such buildings were 20th century dreams and should have little place in our world today.”
Roaf says this is not an easy message for architects who have not been trained in the performance of buildings and have focused largely on creating ‘sculptural statements’ and ‘works of art’ rather than functional buildings. It is also difficult for people who have specialised in increasing the machine efficiency of buildings.
“Plan A is no longer working, however. It's time for Plan B,” she concludes. “Good architecture and building engineering is crucial to human survival, and we need joined-up thinking to make sure it happens – to build a locally focussed, low-carbon world and at the same time create new markets, new prosperity and a new future for Scotland.”