Do Curtains Reduce Heat and AC Costs?

In a Dubai summer the sun is the biggest single source of heat entering most homes, and nearly all of it comes in through the glass. Curtains will not replace air conditioning, but the right ones, used the right way, can make a sun-facing room noticeably more comfortable and take some of the load off the AC.

How much they help depends on what the curtain is made of, how it is hung and how you use it.

How curtains keep heat out

Sunlight passes through the glass and warms whatever it lands on: the floor, the sofa, the walls. Those surfaces then release that heat into the room. A curtain intercepts the sunlight before it reaches them, and a lined curtain also traps a layer of still air against the window, which slows the heat that does get through.

The key is to stop the sun before it warms the room, not after. A curtain closed in the morning on an east-facing room, or in the afternoon on a west-facing one, does far more good than one closed once the room is already hot.

Thermal and blackout linings

A lining is the most effective upgrade for heat. Thermal and blackout linings are denser than standard ones and block far more of the sun's energy. A lining with a light or reflective side facing the window bounces more of the sunlight back out through the glass instead of absorbing it.

Fit matters as much as fabric. Heat, like light, gets round the edges, so the same rules apply as for a dark bedroom: mount the track high, extend it past the frame and let the curtain reach close to the floor.

• Choose a lining with a pale side facing the glass.
• Close sun-facing curtains before the sun reaches the window, not after.
• Keep the curtains a little away from the AC vents so the cooled air can circulate.

What sheers do, and do not do

Sheer curtains soften glare and cut some of the sun's heat while keeping the room bright, which makes them the curtain you can leave closed all day. On their own they will not keep a west-facing room cool on an August afternoon, but they make a real difference to glare and to how hot the floor and furniture become.

This is why layering is so popular here. With a sheer and a lined curtain on a double track, the sheer handles everyday glare and privacy, and the lined curtain comes across during the hottest hours.

Will it lower my bill?

Any heat a curtain stops is heat the AC does not have to remove, so a well-chosen curtain can reduce how hard the system works in a sunny room. How much that saves depends on the size and direction of your windows, the glass, your insulation and how you use the curtains, so we would be wary of anyone who promises a precise percentage.

What you will notice straight away is comfort: less glare, cooler floors and furniture, and a room that holds its temperature better through the afternoon.

Motorized curtains and schedules

Curtains only keep heat out when they are closed at the right time. A motorized track can close the sun-facing curtains automatically at midday, even when no one is home, and open them again in the evening. For a villa with several west-facing rooms, that consistency is where much of the benefit comes from.

Find out what suits your rooms

Which rooms get the most sun, and when, is easier to judge in person. On a free home visit our consultant looks at each window, shows you thermal and blackout linings against your own glass and quotes for exactly what each room needs.