With the Energy Bill 2011 currently progressing through the House of Commons, Cathedral Works Organisation (CWO) cautions historic building owners over taking radical energy efficiency measures. The contractor warns that property owners seeking to go green are in danger of harming their buildings since certain steps to avoid energy wastage, such as insulation, are not always compatible with heritage structures.
Bernard Burns, Managing Director of CWO comments: “It is key that the UK meets its carbon targets however, historic buildings need to be treated carefully since they weren’t constructed to be air tight. Insulating older properties can introduce problems, particularly humidity since historic buildings have their own natural ventilation and were not designed for high levels of heat. In addition, over-heating can lead to cracking in the timber and plasterwork causing long-term damage to the fabric of the building.”
Historic building owners should not underestimate the efficiency of their buildings. Recent research from the Society for the Protection of Ancient Buildings (SPAB) suggests that standard U-value calculations underestimate the thermal performance of traditionally built walls. In its study SPAB measured the heat loss through traditional walls and compared the results with the theoretical values produced by BuildDesk U 3.4 software. It found that 79% of the traditionally built walls sampled performed as much as three times better than the software predicted.