Climate change: evidence review of mitigation options in the Built Environment sector

Executive summary

• This evidence review is based on a systematic literature review of over 80 papers on the wider impacts of climate change mitigation in the built environment sector. The review looked at qualitative and quantitative sources of relevance to the Scottish context. Particular consideration was given to the impacts from an equalities perspective.
• Overall the evidence base suggests there are a number of potential co-benefits associated with climate change mitigation measures in the built environment sector, with health and fuel poverty reduction benefits associated with increased energy efficiency identified as a key theme. It is important to note that the extent of co-benefits is dependent on how and where policies are implemented and consumer understanding and uptake.
• There is strong evidence that improved energy efficiency ( e.g. through insulation) can result in warmer homes which can lead to substantial physical health benefits. These health benefits relate to reductions in disease and mortality. The elderly and young children, in particular, may benefit. Mental health benefits are also identified and include reductions in stress, e.g. due to mitigation of concerns over high energy bills and household debt.
• For physical health benefits, several methods exist to quantify and to capture these benefits. To quantify in the Scottish context further work is required. In terms of quantifying impacts, household dynamics ( e.g. in relation to differing thermal comfort levels and ventilation needs) and the challenges inherent in quantifying human behaviour need to be acknowledged.
• The fuel savings associated with increased energy efficiency can be substantial. There is, however, the potential for rebound effects where cost savings may result in the uptake of more carbon intensive behaviours or increased consumption. However, these could be considered as co-benefits if they help increase quality of life and reduce social inequality.
• Energy efficiency also offers benefits for the non-domestic sector including cost savings and increased productivity.
• There is increasing interest in and correspondingly an emerging literature on Green infrastructure (strategically planned and managed networks of green spaces). Green infrastructure offers many benefits including reducing the urban heat island effect, which can reduce health risks to occupants especially the elderly. It can also offer well-being benefits, reflecting the importance of access to green spaces on the health of people of all ages.
• Behaviour change, e.g. turning down the thermostat, can result in carbon reduction in the short term, and offers participants financial benefits. Challenges include the provision of clear guidance and the scalability of results. Though the literature is in the early stages, smart metering has been shown to bring sustained changes in behaviour and can act as a tool for engagement at the community level.
• The reduction in use of fossil fuels, either through avoided energy consumption, the use of less energy-intensive materials or the use of low carbon energy sources ( e.g. solar) and more efficient heating, cooling and lighting technologies can offer air quality benefits. Emission savings depend on the source of heat or power currently used.
• The use of sustainable building materials offers several potential co-benefits, e.g. through the diversification of forestry and agricultural co-products. Further research is required to better understand the implications for employment.