External Wall Insulation (EWI) by Saint-Gobain Weber has been specified for the thermal and aesthetic upgrade of hard to treat properties in Camborne, Cornwall. Residents of the sheltered accommodation housing scheme are already feeling the benefits of the recent application of weber.therm EWI.

Over 200 properties belonging to Coastline Housing Limited have received the weber.therm XP EWI remedial treatment in a project being run by the main contractor Mark Group. The houses and bungalows, built around 1953, are of a variety of wall construction types including solid brickwork and some with part cavity construction, but it was agreed that only weber.therm EWI would bring the properties up to adequate thermal efficiency.

The Coastline brand, which owns over 3,800 homes across Cornwall, includes Coastline Services which offers top quality repair, maintenance and refurbishment services for their properties. Coastline have obtained funding support through CESP – Community Energy Saving Programme – in association with energy provider EDF to carry out whole house energy efficiency measures to 450 households in the Camborne South and West Lower Super Output areas.

Coastline’s own property team, together with Mark Group, has co-ordinated the project assembly and ‘before’ and target U-value calculations, and the resulting EWI system specification was made by Saint-Gobain Weber’s technical team. The aim was to deliver a target U-value of 0.30 W/m²K from a very poor 2.22 W/m²K to ensure improved comfort for residents, reduced energy consumption and CO₂ emissions.

The weber.therm XP EWI and render system effectively encapsulates the building with the specified thickness of insulation material which is then coated with a weather-proof render finish. In the Camborne project 40mm of phenolic (PHS) insulation board has been mechanically fixed to the sound, existing substrate. The first coat of weber.therm M1 render is applied at 6mm thickness and the reinforcing meshcloth laid onto the render while a second 6mm coat of render is applied to provide a strong 12mm render coat.

weber.therm systems use factory-batched renders manufactured from factories in Bedfordshire, Shropshire and Ballyclare, NI. weber.therm XP uses a polymer modified, through-coloured, lightweight mineral render with One-Coat Technology, and is recognised for its contribution to minimising programme works by reducing the drying time associated with a traditional two-coat render. All weber.therm systems offer a low maintenance and durable protective surface with a choice of attractive finishes and colours. The final finish at Camborne was created with a dry dash aggregate in cream which was applied to maintain the original aesthetics of these properties. Application was carried out by Saint-Gobain Weber-approved applicator, Mark Group.

Chris Kendall, Mark Group’s project site manager, reports that residents are already complimentary about the thermal improvement of their properties. “The project was completed during the summer months so we didn’t expect any feedback from residents until this winter. However, comments were received immediately and with the chilly nights, improved performance and comfort without the need to turn on the heating was very encouraging. The homes have maintained their traditional dash finish, look smart and in good condition, and we know their efficiency is dramatically improved.”

Around seven million properties in the UK are built with un-insulated sold brick walls, with a further one million timber clad solid wall buildings that could also benefit from insulation.

“The current installation rate for solid wall insulation is around 50,000 homes per year,” says James Mead, head of product management, Saint-Gobain Weber. “Green Deal & ECO, which will effectively replace schemes such as CESP, could lead to a significant increase to more than double this annual rate by 2015. ECO subsidies focus on hard to treat properties, such as those with solid walls, ensuring significant growth in the market for External Wall Insulation.”

For further information about Saint-Gobain Weber’s External Wall Insulation systems please  visit www.netweber.co.uk