Micro-climate modification and potential for reduction in summertime over-heating in social housing, South Wales (UK)

There is a growing consensus that the climate is changing faster than at any time in the past millennium. This is likely to have major effects upon many aspects of the built environment. UK Climate Impact Projections 09 indicate significant increases in Summer Mean Temperatures. This may suggest a requirement for cooler buildings during the summer months. In consequence, that would likely lead to an increase in demand for mechanical ventilation and comfort cooling. In the UK, the energy balance used in modifying environmental conditions could change from one predominantly concerned with winter heating, to a situation in which more energy is used to provide summertime cooling.  
This paper reports a research project, funded by the European Union Social Fund, in collaboration with United Welsh (Housing Association).The project aims to develop guidance for low carbon and ecological social housing in South Wales and is concerned with design and construction. Evidence already suggests recently constructed dwellings are overheating even now, under current summertime conditions. With a possible life span in excess of sixty years, they must be suitably adapted for changed climatic conditions, if they are to remain fit for purpose throughout. With the prospect of a Mediterranean type climate, external spaces around dwellings will become more important as levels of outdoor activity increase. The psychological benefits of green space, and its amenity value to residents is well recognised. Some innovative approaches to surface water management and enhancement of biodiversity focus upon the benefits of external landscaping. This research investigates whether a better understanding of how such factors influence the local micro-climate could deliver benefits in terms of improved internal conditions, and reduced energy use. 
The methodology adopted takes  a recently completed new-build social housing scheme from the portfolio of the industrial partner, and using recognised thermal modelling packages, seeks to establish if, and to what extent summertime overheating is currently an issue, and how this may be impacted by climate change. Utilising 
‘ENVI-met’, a micro-climate simulation model, notional changes in the form of specific landscape measures are then assessed in terms of their influence upon the local environment. This data is finally used in a further iteration of modelling, to evaluate the impact of micro-climatic modification and ventilation strategies on the internal environment of adjacent dwellings. 
This paper will be useful to Registered Social Landlords, Local & Regional Government Agencies, and Private Sector organisations engaged in the planning, design and procurement of residential buildings.