High energy costs have percolated into our day-to-day household budgets increased over the last decade. This applies particularly to windows, where glazing is a considerable factor in heat retention.
Thermal Properties of Glazing
The accepted standard for measuring the energy performance of windows is called the ‘U’ value measurement – also used for floors, walls, and roofs. Traditional single-pane windows have a U value in excess of 5, whereas double glazing compares with over 3.
However, there has been considerable innovation in window manufacturing over the last few years, and building regulations now stipulate a U value of no worse than 1.6 for new window installations.
Improvements include wider cavities between the two glass panes, an inert cavity gas such as argon, low emissions coatings reducing heat loss and design improvements. To put this in perspective, walls are expected to have a U factor of less than 0.3, which highlights windows as the weak spot in thermal efficiency.
Double or Triple?
Triple glazing is more widely used in colder regions such as Scandinavia to achieve a U value of 0.8 minimum. This requires not just three layers but an insulated frame, which comes with higher manufacturing costs. Double glazing in Tewkesbury, however, is not exposed to the same extremes of climate.
The payback on thermal savings alone takes a long time because of the small energy savings, so is triple glazing worth it?
There are other factors to consider, with one being comforted. If you insulate the rest of the house and ignore the windows, you will end up with cold spots, causing draughts that draw heat away from you and condensation. Triple glazing is simply more comfortable.
Glass absorbs heat and can contribute to the warmth of the room when the sun is shining, but does this make sense in a climate like ours? It’s well worth investigating double glazing in Gloucestershire by Firmfix – a company with experience in the English climate and that can provide more information.
For more answers, see https://www.thegreenage.co.uk/triple-glazing-is-it-worth-it/.
Further innovations are always underway, such as quadruple glazing or new coatings, but it seems that the jury is still out on the costs vs benefits of double vs triple glazing. We could always do that old-fashioned thing and draw the curtains after dark – it all helps to keep homes warm in the depths of winter.
