Improved thermal efficiency for webertherm External Wall Insulation (EWI)
23 02 2012
Saint-Gobain Weber, the UK formulator and manufacturer of innovative materials in the façades, exterior wall insulation, concrete repair, tile and floor sectors, has improved their BBA certificated and EST recommended webertherm External Wall Insulation (EWI) expanded polystyrene (EPS) system, making it even more thermally efficient. With the simple exchange of white EPS boards to super-efficient grey EPS boards, the system is now 20% more efficient.
The versatile, award-winning Saint-Gobain Weber EWI systems uses various types of insulation, but EPS has played an important part in the successful aesthetic and thermal upgrade of hard-to-treat solid wall properties for many years offering an efficient, reliable and economical solution. The new grade polystyrene boards, grey in colour due to the graphite content, provide improved performance levels achieving a lambda value of 0.030 W/mK against the 0.038 W/mK value of white EPS boards.
Thinner grey boards can achieve the same U-value as a thicker white board so requiring less insulation by volume. For example, a 110mm thick white EPS board can be replaced with 80mm thick grey board and still achieve the same performance value. Shorter fixings and narrower full system beads will add to this saving while applicators will find that the lightweight thinner grey boards are easier to detail around windows and openings making fitting and installation simpler, another important factor contributing to greater savings and reduced project costs.
Grey EPS boards offer excellent and consistent thermal performance and are produced in accordance with the requirements of BS EN 13163 – Thermal Insulation Products for Buildings. They have an A+ BRE Green Guide to Specification rating contributing to essential eco points in materials credits in a Code for Sustainable Homes assessment.
webertherm grey EPS boards are available in a standard size and in a range of 20 – 200mm thicknesses. The choice of insulant is dependent on the thickness of the board which can be accommodated and Saint-Gobain Weber will calculate the correct product specification and system to meet the target U-value in each project. Under the Decent Homes programme, and more recently under energy supplier-obligated schemes such as CERT (Carbon Emissions Reduction Target programme) and the solid wall community scheme known as CESP (Community Energy Saving Programme), funding opportunities will continue with the introduction of the ECO programme which will combine with Green Deal financing to open up the market for private and rented sectors.