As we move into the colder months of the year we tend to think about better ways of insulating our home. With windows being the main culprit for heat loss (up to 40% in some houses) it makes sense to look at the various windows furnishings on the market to see what is going to provide the best insulation.
There has been a lot of misinformation and anecdotal evidence in the market around the thermal benefits of window coverings, in particular curtains. To help consumers make an educated decision our friends at Consumer NZ have gone out and performed a number of tests to understand once and for all the impact that curtains have on insulating a room. You can learn all about their finding here - ConsumerNZ
In summary their tests showed that almost all curtains are insufficient at insulating your home. Although fabric choice and quality had a small part to play the main reason was due to the air gap around the curtain that resulted in air movement (the reverse chimney effect) transferring cold air from the window and replacing it with warm air from the room.
The testing found the closer the material was to the glass and the smaller the air gaps between the frame and the material then the better the insulation was. Surprisingly, old fashioned net curtains were more effective at reducing heat loss. This is due to how close they sit next to the glass and the airflow being disrupted by the close weave netting.
Unfortunately they did not test roller blinds however considering a roller blind generally has smaller light gaps around the window frame and can sit very close to the glass, your thermal protection should be far higher than with curtains. You also have a selection of thermal backed fabrics that you can choose from for additional heat loss prevention. We believe that sunscreen blinds also hold some heat saving characteristics for the same reasons that net curtains do and they can be fitted even closer to the glass.
Finally roller blinds tend to be more cost effective than curtains and can be ready to start insulating your home in a week where curtains can take 4-6 weeks before they are ready.
If you want to learn more about air gaps on blinds you can at www.urbanblinds.co.nz/news/light-gaps/