Refurbishment and Restore Issue 11 2018 | Page 48

Welcome to the retrofit revolution Rising fuel bills are fast making insulation and secondary glazing essential for period properties. Mitchell & Dickinson has developed groundbreaking solutions and its director Mukti Mitchell tells the story of glazing one of the most beautiful estates in the UK ‘W e’ve had significant experience of secondary glazing windows in period properties since we launched our unique CosyGlazing system seven years ago,’ says Mukti. ‘And while we’ve secondary glazed lots of domestic properties, an area for development has been working with listed buildings on private estates. We’re currently in the third year of insulating the entire village of Clovelly on the North Devon coast, with three years remaining. ‘The stunning listed village by the sea gets a battering from the elements in winter, and so the objectives of estate owner John Rous were to improve warmth and comfort for tenants, reduce heating bills and raise the Energy Performance Certificate (EPC) ratings to E or above. ‘John commissioned a number of test properties before proceeding with the insulation of the entire village of 114 homes. Due to the heritage of the village, we chose to start with measures that least affected the historic fabric of the buildings. ‘We focused initially on those that attract the highest level of grants under the ECO scheme, which were sloping ceiling insulation and loft installation. In the first phase we completed 50 properties with these two measures, complemented by draught proofing. In phase two we added an advanced secondary glazing system.’ Loft insulation is relatively straightforward, but key concerns are avoiding burst pipes and condensation. 100mm or less of insulation allows warmth up from the house which stops pipes bursting, so when this is topped up to 300mm, loft temperatures can drop significantly. Therefore all pipes must be meticulously lagged, ensuring every single inch is covered and all joints must be taped. Many bedrooms in the village have either a small area of flat ceiling above the middle of the room and sloping ceilings going down from there to a low solid wall, or vaulted ceilings. The slopes have no more than a sheet of plasterboard between the room and the space between the rafters through which external temperature air flows up to the loft to keep the rafters and beams in good condition. 