TECHNICAL FOCUS
AN EFFICIENT APPROACH TO WINDOW SPECIFICATION
From the desire to increase the sustainability of a building to the very real need to reduce its impact on the environment, it is important to view windows in terms of their thermal efficiency. Andrew Cooper, National Specification Manager from leading aluminium fenestration solutions supplier Senior Architectural Systems, discusses some of the ways aluminium windows can provide both a compliant and creative solution to Part L of the Building Regulations. we talk about the W hen thermal performance of fenestration, what we are really concerned about are U-values. Put simply, when it comes to U-value ratings, less is more and the lower the figure, the more heat is retained. The U-value of a window system is dependent on a number of factors including the frame material, the type of glazing and the use of a warm edge spacer bar which provides the space and insulation between the two or three panes of glass. Although BREEAM, Passivhaus and other such standards have helped to encourage the wider specification of energy-efficient building materials and processes, the required U-values for both domestic and non-domestic dwellings are determined by Part L of the Building Regulations – and these figures are set to change. Although the specific timings and targets of the new legislation are yet to be
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confirmed, one thing that is for certain is that the U-values target will be lowered. It is also very likely that further reductions will be introduced in the future so now is the time to factor achieving the best possible U-values into your specification plans.
Future-proof fenestration The planned changes to Part L will shake up the construction industry – after all, its specific aim is to challenge us all to think more carefully about the impact that the built environment has on the wider world. However, for many fenestration system manufacturers, planning for such a change has been years in the making and rather than the new legislation being seen as a minimum target, it has helped fuel innovation to provide solutions that not only meet but exceed current requirements.
