Australia experiences extremely hot summers, and in many suburbs there are no inherent breezes to alleviate the heat. Indeed, if you are lucky enough to live along the coast, you may possibly have more relief from the heat with the presence of a decent coastal breeze.
As most homes comprise a considerable percentage of glass in the form of windows, it is pertinent to note that glass is a conductor, and as such allows exterior heat to very easily pass through into the interior. You only have to stand close to an exposed window on a hot day to feel the radiant heat. It is not uncommon for some to receive third degree burns from touching glass windows on a very hot day.
There are a few ways to prevent this:
- Purchase very expensive eGlass or double glazed windows, which will still require something extra on really hot days.
- Install exterior blinds or shutters to prevent heat touching the glass.
- Install thermally lined curtains or blockout blinds inside.
It has been scientifically proven that fully lined curtains can reduce heating and cooling costs by up to 40 per cent in Aussie homes. Sheer curtains have no thermal benefits as they generally have a more open weave and allow heat to pass through. Sheer curtains billowing in the breeze may seem “cool” but you need a breeze for that illusion. And yes, it is an illusion; if the breeze passes through the fabric, then it is not insulating. Given the extreme summers in Australia, we cannot simply talk about the illusion of coolness; we have to utilize the most effective coverings we can on our windows to actually decrease the temperature inside.
To keep your home cool in summer, close your heavy drapes or blockout blinds first thing in the morning. When the outside temperature lowers in the afternoon or evening, that is the time to open them to allow any breeze or cooler conditions to pervade. Certainly, have sheers on the window if that is your taste, as they do serve numerous other functions, but remember you will need some sort of blockout option on the windows also to keep the heat at bay.
This is not 21st century high-tech information. Our forebears used this basic knowledge to cool their homes long before electricity and air conditioning.