R E V I E W A N D A N A L Y S I S 29 PREPARING FOR CLIMATE CHANGE JOHN PRESTON T HE HERITAGE sector needs to contend with risks arising both directly from climate change, and from perceptions of old buildings as obstacles to climate change adaptation. This briefing gives pointers for dealing with both of these challenges, introduces the work of some of the key organisations involved, and highlights key sources of further information. Most heritage sector publications suggest that the buildings of traditional construction form up to 25 per cent of the UK’s building stock, but this could be up to 35 per cent according to a Building Research Establishment (BRE) literature review ( Solid wall heat losses and the potential for energy saving) published by the Department of Energy and Climate Change (DECC) in 2015. In either case, the role of these buildings in climate change is clearly substantial and is arguably the single most important issue faced by the conservation sector. EXTREME WEATHER EVENTS The 2018 Intergovernmental Panel on Climate Change (IPCC) Special Report highlights that an increased risk of extreme weather events will occur with increasing frequency, including heavy rainfall and flooding. For traditional buildings, this could have a particularly high impact, bringing rainwater disposal systems and the capacity of traditional materials to cope with such extreme conditions under serious pressure, and putting buildings that are already in poor condition or under repair at high risk. The immediate challenge is how to cater for increasingly severe weather events with the security of traditional buildings in mind. Good building maintenance is vital. Measures such as increasing the size of rainwater goods can be considered, but these often occur at the expense of the building’s original character and fabric, which may not deal well with driving rain. Historic England’s Flooding and Historic Buildings gives guidance on how to manage flood risks and improve resilience in relation to historic buildings, and on dealing with the consequences if the worst should happen. Any measures taken should be appropriate to the building’s character and performance. STRATEGIC MITIGATION CHALLENGES The IPCC Special Report calls for radical change to help mitigate the effects of climate change within 12 years, bringing even greater urgency to existing government retrofit strategies. The government’s Clean Growth Strategy (2017) wants all fuel-poor homes, as many privately- rented homes, and as much social housing as possible to reach Energy Performance Certificate (EPC) band C by 2030, with as many homes as possible to achieve this target by 2035 ‘where practical, cost-effective, and affordable’. Such practicalities are, however, conspicuously absent from the Committee on Climate Change’s independent assessment, which notes that 19 million UK homes out of 27 million (70%) are currently below band C. Reading between the lines, the implementation of these targets (coupled with the current disregard for heritage significance) could amount to the single biggest threat to historic and traditional buildings and areas. The government overlooks the need to put buildings into good repair before installing retrofit measures, and government-promoted retrofit schemes have taken a one size fits all approach, assuming that what will work for buildings of modern construction will also work for traditional buildings. These challenges overlie a longstanding crisis in training for the conservation and repair of traditional construction. The 2013 Skills Needs Analysis of repair maintenance and retrofit published by English Heritage, Historic Scotland and the CITB noted that 89 per cent of contractors working in this sector were general construction companies, and 87 per cent did not have formal qualifications relating to working on traditional buildings. These deficiencies, multiplied at scale as retrofit targets bite, are detrimental Condensation on leaded light windows: simple modifications such as secondary glazing can reduce heat loss through historic fabric with minimal effect on character.