Window coverings reduce heat gain in summer and heat loss in winter by acting as a barrier at the glass, which means heating and cooling systems run less often. Choosing the right type, matched to your window’s orientation and the season, is one of the most accessible upgrades for reducing home energy use without replacing the windows themselves.
Heat loss and heat gain through windows is one of the main drivers of energy waste in homes. In warmer months, sunlight entering through glass raises indoor temperatures quickly. In colder months, warmth escapes through the same surface, increasing the load on heating systems.
Most people focus on appliances or lighting when looking for savings. Window coverings are often overlooked, yet windows account for around 30% of heat loss in winter, and in summer up to 76% of sunlight through double-pane windows converts to indoor heat. The right coverings address both problems.
The material, construction, and thickness of a covering all affect how well it manages heat. Material choice is one of the most important decisions. If you are considering natural timber options, the sustainability of basswood and cedar in blinds production is worth understanding before you buy.
The table below shows how common covering types perform across the main energy efficiency factors.
| Covering Type | Insulation | Summer Heat Block | Winter Heat Retention | Adjustability |
|---|---|---|---|---|
| Honeycomb (cellular) blinds | High | Good | Good | Moderate |
| Lined or thermal curtains | High | Moderate | Good | Low |
| Roller blinds (blockout) | Moderate | Good | Low to moderate | High |
| Timber shutters | Moderate | Good | Moderate | High |
| Venetian blinds (aluminium) | Low | Moderate | Low | High |
| Sheer curtains | Low | Low | Low | High |
Honeycomb blinds trap air in their cells, which creates insulating layers at the glass. Lined or thermal curtains perform similarly when drawn fully. Shutters offer adjustable control and reasonable insulation. Thin or single-layer blinds provide less insulation but still block direct sunlight.
Coverings can be installed inside or outside the home. Each location performs differently.
| Feature | Internal Coverings | External Coverings |
|---|---|---|
| Heat blocked before entering | No | Yes |
| Ease of installation | High | Moderate to high |
| Weather resistance needed | No | Yes |
| Aesthetic range | Wide | Moderate |
| Summer performance | Moderate | Better |
| Winter insulation | Good when layered | Low (typically open) |
External coverings such as external roller shutters and awnings intercept sunlight before it reaches the glass, which is more effective at reducing summer heat gain than internal coverings acting on heat already inside the room.
Internal coverings, particularly thicker options, are more effective for retaining warmth in winter and offer a wider range of styles.
Layering both types delivers the best year-round result, particularly on windows exposed to direct sun or strong seasonal temperature swings.
Where a window faces determines how much sun it receives and at what angle. Using the right covering for each orientation makes a measurable difference to indoor comfort.
North-facing windows receive sun through winter. External eaves or pergolas can block high summer sun while still allowing lower winter sun to warm the room. Internal curtains or blinds add insulation at night.
East and west-facing windows receive strong, low-angle sun in the morning and afternoon respectively. These benefit most from adjustable coverings, such as shutters or Venetian blinds with adjustable slats, that can track changing light angles through the day.
South-facing windows receive little direct sun but lose heat readily in winter. Thicker curtains or insulated blinds reduce overnight heat loss without needing to block light.
Using the right coverings consistently produces compounding benefits over time.
Where savings come from:
Window coverings are one of the simpler ways to improve efficiency without construction or window replacement. For a broader view of sustainable product choices, the eco friendly blinds guide covers materials and production considerations that affect long-term impact.ment.
Getting the most from your coverings depends on how you use them, not just which type you buy.
They act as a barrier at the glass, slowing heat gain in summer and heat loss in winter so heating and cooling systems run less.
Thicker, insulated coverings such as honeycomb blinds, lined curtains, and shutters generally insulate better than thin single-layer blinds, and layering improves results.
Lighter colours reflect more sunlight, which helps reduce heat gain in rooms with strong sun exposure.
Yes. The right coverings, matched to window orientation and used correctly, reduce heat transfer without replacing the windows.
Close coverings during hot summer days, open them for winter sun then close before nightfall, and adjust slats or layers to control light and temperature.
Energy efficient window coverings work best when the type is matched to the window’s orientation, the season, and your daily habits. Thicker and layered options insulate most effectively. Adjustable styles give you control over light and heat throughout the day.
Used consistently, they reduce the need for heating and cooling without structural changes to your home.
The team at Blinds Deal can help you identify the right coverings for each room. You can shop online and have your order delivered directly to your door.
