For pure thermal performance, double curtains generally come out ahead.
A double curtain setup — sheer on one track, blockout on the other — covers the full window wall, extending past the frame on both sides and down to the floor. That extra coverage beyond the glass is what makes the biggest difference to heat retention, particularly on large windows and sliding or stacker doors.
Blockout roller blinds are a strong, tidy option and do insulate — but because they're sized to the window opening rather than the wall, there's less overlap beyond the frame, so some warmth still escapes at the edges compared with a full curtain setup.
For a Melbourne home with large glazing or a sliding door prone to cold nights, double curtains are usually the stronger winter investment. For a smaller window where a cleaner line matters more, a well-fitted blockout roller blind is still a solid step up from bare glass.
FAQs
Do blockout roller blinds or double curtains insulate better?
Double curtains generally insulate better than blockout roller blinds, because they cover the full window wall — extending past the frame and down to the floor — rather than being sized to the window opening alone.
Are blockout roller blinds still worth it for warmth?
Yes — blockout roller blinds are a solid step up from bare glass and work well on their own or layered with curtains, even though they don't cover as much extra area as a full curtain setup.
What's a double curtain setup?
A double curtain setup uses two tracks — typically sheer on the inner track for daytime softness and privacy, and blockout on the outer track for night-time darkness and insulation.
Which is best for a sliding or stacker door?
Full-wall curtains, extending well past the door frame, tend to outperform other window furnishings on sliding and stacker doors because they cover the widest area with the fewest gaps.
Related reading
Want a warmer room? [Book a Free Measure & Quote](/contact) with Tiptop Blinds — in-home, across Melbourne.
