Designing for Future Climate Scenarios
The climate is changing. Considering the life expectancy of our buildings this will particularly impact on the construction industry. The majority of buildings constructed today will still be in use in the second half of this century when wetter winters and drier summers will affect existing buildings and alter the requirements of new ones. Whatever the cause of climate change, we will need to adapt our buildings so that they can cope with higher temperatures, more extreme weather and changes in rainfall. According to scientific data climate change is likely to cause a rise in average temperatures by 4-6 degrees over the next 80 years.
Current climate trends already show, we will need to adapt our built environment, to deal with a climate that will be significantly different from that in which it evolved. During the heat wave in 2003 in France, there were 14,802 heat-related deaths mostly among the elderly (French National Institute of Health). Most people did not know how to react to very high temperatures and most residential facilities built in the last 50 years were not equipped to perform under these conditions. Projections prepared by the Oxford Institute for Sustainable Development (Oxford Brookes University) show that most homes in the UK will suffer from overheating in summer beyond 2050 and some already from 2030.
Already there has been an increase in the average number of Cooling Degree Days (CDD) in the UK, between 1961 and 2006. At the same time the average number of Heating Degree Days (HDD) in the UK has decreased between 1961 and 2006, and future UK weather scenarios indicate a further 30% decreased number of Heating Degree Days by 2080. These results are consistent with research carried out by the CIBSE.
Although there is a growing consensus amongst scientists that the climate will change, we still design and optimise our buildings based on past experience. Building designers generally use weather data from the past to optimise their designs and simply assume that the weather will remain consistent.
Enabled by funding from the Technology Strategy Board, Gale & Snowden has been at the forefront to develop integrated design strategies that help to extend the useful life of a building. By using future probabilistic weather data, building designs can be future proofed against the effects from climate change without necessarily adding costs to a project. Results from these projects have indicated that the same low energy passive design principles that help to reduce heat losses can be equally successful to future proof a building against the risks of climate change and reduce the frequency of overheating in summer as long as a successful ventilation strategy can be implemented. Some strategies more typical for buildings in Southern European climates could become applicable for the UK under future UK weather scenarios.
Climate change requires a fundamental change in the way we think about design; changing from approaches that are based on past experience to those that are based on calculated projections of future climate.
A life cycle cost analysis, carried out by Gale & Snowden as part of the TSB funded research showed that if these strategies are implemented subsequently together with the regular maintenance cycles the building can be future proofed against climate change at little extra costs with the economic benefit of extending the useful life of the building.
Climate change adaptation is becoming a greater concern for clients. To ensure comfort and commercial viability building designers need to assess the potential impacts from climate change from the outset. Gale & Snowden’s integrated team of design professionals have the skills to carry out climate change risk analyses, to develop solutions and climate change adaptation strategies.