Insulating your windows with Blinds & Curtains
Style that saves — comfort you can feel, efficiency you can measure.
Even in a well-insulated home, up to 45% of heat can still be lost through your windows. In an uninsulated house, that figure drops to around 30%, as heat escapes more easily through walls, ceilings, and floors.
That’s why your choice of curtains or blinds matters.
The right window coverings can prevent up to two-thirds of heat loss through your windows — helping you stay warmer and save on energy.
Consumer NZ has conducted a study on the effectiveness of different types of blinds and curtains in retaining heat.
The research shows that choosing the right window covering can make a noticeable difference to a home's insulation performance and energy efficiency. Options like honeycomb blinds and heavy, floor-length lined curtains perform significantly better than bare windows or lightweight treatments.
Source: Consumer NZ – Curtains Insulation Study
consumer.org.nz/articles/curtains
Honeycomb Blinds - the clear winner
Based on the Consumer NZ study, the best-performing product for insulation is:
Honeycomb blinds
Heat Retained: ~60–70%
These are the most effective window coverings in the study, outperforming all types of curtains and other blinds.
Their cellular structure traps air in pockets, creating an insulating barrier that reduces heat loss through windows.
For comparison:
Heavy, floor-length, lined curtains retain about 28% of heat.
Thermal, sill-length curtains retain about 17–18%.
Wooden venetians (closed slats) retain around 26%.
Bare windows retain 0%.
So if insulation is the priority, honeycomb blinds are the clear winner.