2019 Yearbook

30 Y E A R B O O K 2 0 1 9 because, as previously mentioned, putting buildings into good repair is a vital precursor to any retrofit measure, and retrofit measures applied without understanding of traditional construction can exacerbate existing problems and create new ones. Anyone familiar with the effects of cement mistakenly applied to breathable buildings can foresee the consequences of applying impermeable insulation to a traditional building – not only is there a risk of damp and decay, but saturated walls lead to increased heat loss. THE HERITAGE SECTOR’S RESPONSE AND THE STBA Problems associated with solid wall insulation and other issues arising from the government’s Green Deal were raised by the Society for the Protection of Ancient Buildings (SPAB) in a letter to The Times in late 2011. This was soon followed by a COTAC conference in November 2011, ‘Improving the Thermal Performance of Traditional Buildings’, from which the presentations are still scarily relevant. Research by the heritage sector (SPAB, Historic England and Historic Environment Scotland) albeit from very small samples of buildings, cast doubts on the government’s approach. The Sustainable Traditional Building Alliance (STBA), brought together sustainability, heritage and mainstream industry interests, under the aegis of the Sustainable Development Foundation, with the National Trust, Historic England, and SPAB as patrons. It challenges industry thinking in relation to traditional buildings and moisture performance. STBA’s research on the poorly understood but vital issue of moisture in buildings is published by the British Standards Institute (BSI) as a white paper. RISKS AND UNINTENDED CONSEQUENCES STBA’s 2012 Planning Responsible Retrofit of Traditional Buildings report prompted DECC to commission a BRE study of solid wall buildings. Its key output was the solid wall literature review mentioned above, which highlights risks and unintended consequences when applying inappropriate measures to heritage buildings. The BRE’s evidence on unintended consequences remains unpublished, but key issues were highlighted by Colin King at Ecobuild 2014, and in the academic study 100 Unintended Consequences of Policies to Improve the Energy Efficiency of the Housing Stock by Clive Shrubsole, Alexandra Macmillan, Mike Davies and Neil May, in the April 2014 special issue of Indoor and Built Environment . The most devastating published evidence has been published only recently in a Passive House Plus article, in relation to solid wall insulation failures in 390 dwellings at Fishwyck, Preston. To date, there remain no safeguards for traditional buildings within Energy Company Obligation (ECO) or other government-promoted schemes. WHOLE-LIFE CYCLE AND THE CIRCULAR ECONOMY Government initiatives for energy conservation and carbon reduction in existing buildings have focused on performance in use, not embodied energy and whole-life cycles. They have disregarded the energy and carbon costs of construction, of manufacture and installation of energy-saving measures, and of demolition or disposal. No consideration has been given to the carbon and financial costs of rectifying inappropriate measures. Consideration on a whole-life basis, would put traditional buildings in a far more favourable light. The increasing focus on reducing waste and the circular economy offers some hope for rectifying this. STANDARDS AND GUIDANCE For appropriate guidance on working with traditional buildings, it is useful to start with the building regulations Part L1B and 2B special consideration for ‘buildings of traditional construction with permeable fabric that both absorbs and readily allows the evaporation of moisture’. British standard BS 7913:2013 guide to the conservation of historic buildings (IHBC branded version available at discounted rate for members) is the key document in terms of overall sustainability and energy efficiency. Two useful BS-published European standards include the little-known sustainable construction standard, BS EN 15978:2011, which supports whole-life consideration, and BS EN 16883:2017 conservation of cultural heritage – guidelines for improving the energy performance of historic buildings . Chapter three of the government’s guidance to landlords and local authorities on the domestic private rented property minimum standard recognises differences in moisture performance between modern and historic buildings; it promotes a whole-house approach (see also STBA’s What is Whole House Retrofit? ). The forthcoming Publicly Available Specification (PAS) 2035 will apply to all publicly funded retrofits including ECO3. It will cover vital but so far overlooked aspects of the process: survey and design, and consideration of the interactions between measures. ADVICE Historic England and Historic Environment Scotland provide technical advice on energy conservation and retrofits. For user-friendly overviews, see SPAB’s briefing Energy Efficiency in Old Buildings and STBA’s Planning Responsible Retrofit . The latter balances energy and environmental considerations, healthy buildings and occupants, and heritage. It promotes the whole building approach integrating fabric measures, services, and how people live in and use the building. It goes on to consider retrofit challenges, problems with standards and regulations, and risks. STBA’s Planning Responsible Retrofit of Traditional Buildings , from which this diagram is taken, aims to promote an integrated whole building approach to retrofit.