The components that make up a window all contribute to its functionality and insulating properties. Frame materials, glazing features, gas fills and spacer bars all play an important part in the performance of windows and doors.
– Consider the thermal conductivity of the frame material when choosing your windows. Comparing timber and aluminium frames, for example - as a raw material, timber is around 800 times more effective as an insulator than aluminium
, and is similarly superior in this department to uPVC. Combined with the sleek, low-maintenance alu-cladding with which we encase our windows, Norrsken’s timber framed windows are, in our opinion, rather unbeatable.
– Single glazing no longer meets current (UK) legislation on thermal performance. (2.0 W/(m2K) is the limiting fabric requirement, 1.4 W/(m2K) recommended [Great Home
]) Double glazing is now one of the most popular forms of glazing and comprises two panes separated by a spacer bar. Heat is trapped between these panes, which slows its escape from the building. Triple glazing follows the same concept but performs better again, as the additional space between the second and third panes of glass slows the heat loss further. In our systems, you can expect 40-50% better performance from a triple-glazed window over a double-glazed version.
Glass types – Double and triple-glazed windows in our systems have one or two panes of Low-Emissivity (Low-E) glass respectively. Heat-reflective coatings in this glass type reduce heat loss from the building by allowing warming infra-red rays into the building but preventing them from passing back out through the glass. Rays that would otherwise be lost to outside are reflected back into the room and disrupt heat loss.
Gas filling – Glazing units today are commonly filled with inert gas (such as argon or xenon) rather than air, which acts approximately 60% better as an insulator than air.
This gas filling minimises heat transfer between the interior and exterior of the window. All our units are argon-filled.
Spacer bars – Spacer bars keep the panes of glass apart in double and triple glazed units, maintaining the all-important ‘air gap’ between glass panes outlined above. There are various different spacer bars available, and the type used will affect the heat loss through your windows. Aluminium spacer bars, for example, facilitate heat loss, while alternatives such as warm edge spacer bars - made from a low conductivity plastic - provide better thermal performance.
Seals – Poor seals and gaskets on your windows and doors will affect air leakage rates and allow heat to escape from your home. Energy efficient windows and doors will often have multiple seals and gaskets, of differing types, which significantly contribute to the performance of the products.