Blinds and shutters act as an extra layer of insulation for windows, helping keep heat in during the winter
Windows, particularly single-glazed and older double-glazed units, are poor insulators – meaning that precious heat can escape.
Blinds and shutters can help reduce this heat loss, saving energy, money and increasing the comfort of your home.
Research conducted by Glasgow Caledonian University has shown that a reflective roller blind is as effective as a pair of curtains in reducing heat loss on single glazed windows. Both reduced the amount of heat lost by 40%, which is great news for heritage properties where glazing cannot be changed.
It’s all to do with U-values. The lower the U-value, the slower the heat loss through the material. So a material with a low U-value is a good insulator.
The best U-value of a heat retaining (low emissivity) glass is around 1.2. As a comparison, building regulations say that walls need to have a U-value of 0.3 (about four times better) and roofs 0.18 (about six times better).
Even with modern coated glazing designed to retain heat in the winter, blinds and shutters can still offer an improvement in U-value, although obviously the effect is less dramatic than with older windows.
What can you do?
Generally, the better insulating blinds are those which are thicker, have reflective coatings, and have air gaps or pocket-like honeycomb fabrics. Blinds fitted in a cassette or frame will improve insulation, as these reduce gaps around the extremities of the blind. Wooden internal shutters are also good insulators, as are some external shutters.
You can see our simple video on how blinds and shutters retain wanted heat here.
For guidance on how to use your blinds and shutters to best effect, see here.
See the other resources about keeping your home warmer on the right hand side of this page.
Your local BBSA member will be able to offer expert advice.