Reducing energy use in housing: insulation and retrofit problems in Wales and the UK

There is general agreement that existing and new build houses should achieve higher standards of energy efficiency. Research into different forms of insulation and methods of installation has been carried out for a new book on insulation materials. (ICE Publications later in 2019). There has been an assumption that all insulation materials are much the same and that, providing that thermal performance figures are satisfactory, any material can be used in any form of construction. The evidence shows, however, that inappropriate insulation and installation measures can lead to many unintended consequences and a gap between predicted and actual performance. Far from reducing fuel poverty and carbon emissions, mould and damp can occur, aggravating health problems, which has been confirmed by academic research. Sealing up increasingly airtight buildings with non-breathable, flammable and even hazardous synthetic materials can cause damage to building fabric and occupant health. Furthermore the embodied energy and pollution involved in the production of many commonly produced insulation materials can be bad for the environment. The importance of indoor air quality and ventilation is often overlooked, though recent work by NICE and the Environmental Audit Committee in Westminster has drawn attention to the problems. The paper will review the range of insulation materials available and their differences. It will be illustrated with case study examples of so-called retrofit disasters where cavity wall, external wall and internal insulation have been wrongly applied. Some of these case study examples are in Wales and the assistance of CIVALLI (based in Newport) will be acknowledged.