Double and triple glazing#
We often see recommendations to replace old double glazing with modern double glazing, but we don’t know when this is a reasonable option and whether it’s to do with the glazing itself or with the likelihood that the windows are draughty.
If you have double glazing and your walls are uninsulated, triple glazing won’t be worth the cost.
If you have single glazed sash and case windows in a listed building, many local authorities will allow you to install slim-line double glazing as visually, it’s hard to tell the difference. If the sash-and-case windows are in good condition, consider keeping the wind and just replacing the glass. Victorian wood was grown slowly so the original wood could have as much life left in it, or more, than modern replacements. If the window frame is thick enough, a good company can just cut a wider channel and insert it. Think about how well the windows fit and whether any draughtproofing or professional refurbishment is needed at the same time. Also think about how ventilation will work for your users - modern windows tend to have trickle vents for better and more comfortable control of airflow in cold weather.