Dr David Strong warns against the dangers of ‘zero carbon’
The enthusiasm for achieving zero-carbon buildings could result in ‘highly perverse outcomes’, according to Dr David Strong, chief executive of Inbuilt Consulting, speaking at last month’s Ecobuild conference in London. He said, ‘I am a strong supporter of zero- and low-carbon buildings, but there is much more to delivering exemplary built environments than zero carbon.’ Commenting on recent prototype dwellings that meet the highest levels (Levels 5 and 6) of the Code for Sustainable Homes, David Strong warned, ‘The single-minded scramble to design and build Level 6 homes gives out the message that this is the highest ambition and most worthy outcome we should aim for. ‘However, if we end up with “zero-carbon” Code Level 6 homes that are uneconomic to maintain, are built on flood plans, overheat in summer, have poor acoustic performance, poor indoor air quality or other unintended consequences, then we have created a generation of homes that are unfit for people. We can’t call this sustainability. The so-called “best” are in real danger of becoming the enemy of the good.’ He believes that addressing the challenge of climate change and delivering genuine sustainability requires whole-system thinking. “This means collaborative, multi-disciplinary, integrated team working live we’ve rarely seen before. ‘It also means working to find natural solutions to reduce our dependence on energy-intensive systems. There are so many opportunities offered by nature to ventilate, heat, cool and illuminate our buildings, and cost savings to be made by designing out unnecessary technical complexity.’ David Strong also questioned the reality of ‘zero carbon’ as a useful label for buildings, and warned that it could offer consumers a false promise. ‘The actual definition of “zero carbon” differs significantly between various Government departments and agencies, and some of the definitions are based on completely unscientific formulas. And anyway, a home is only “zero carbon” in the sense that it complies with a theoretical carbon requirement. It’s how we use a home that really matters.’ He also warned against the danger of being distracted from the vital challenge of reducing carbon emissions from the existing building stock and of securing investment and planning permission for large-scale renewable-energy systems. ‘In terms of pounds Sterling invested per tonne of carbon saved, both of these objective will provide a much greater and faster return than making all new homes “zero carbon”,’ he stressed.