Ultra Thin Double Glazing for Listed Buildings?
Is The New Generation of Vacuum Glazing The Answer for Listed Buildings?
There is no doubt that owners of Listed Buildings or those in Conservation Areas often have the least energy efficient properties that add to increased energy use for heating and adds to our carbon emissions.
But it’s understandable that Planning and Conservation Officers want to ensure we retain the architectural fabric including period sash and casement windows.
Their concern? The use of un-sympathetic replacement windows with chunky profiles, standard slim double glazing where you get the tell-tale ‘double reflection’ through the glass, and double glazed units which have an un-acceptable failure rate.
The new generation of ultra-slim vacuum glazing can solve these problems. Two panes of glass separated by a space of around 0.5mm which has the air evacuated to create a vacuum, the same principle as a vacuum flask. This creates a double glazed unit barely the thickness of a single pane of glass, with incredible energy insulation equal to triple glazing, sound absorption equal to acoustic glass and a long life expectancy of 25 years.
So the depth of internal mouldings can be retained. The glass acts ‘as one pane’ avoiding the double reflection and the risk of deepening rebates (reducing wood) to hold thicker, heavier units is prevented.
The downside? Vacuum glazing does have tiny spacers that hold the panes from touching under atmospheric pressure. These, in reality, are not visible when installed except for certain light conditions. And there may be an evacuation port and getters that are in the corner of the panes of glass. Yes these are visible close up but in actual installations soon blend into the background as they would always be placed out of the sight line, hidden behind curtains or blinds etc.
So take a look at vacuum glazing, it may just be the answer to better insulation of Period and Listed Buildings.