Passive Shading
Shading the sun is vital to keep your house cool in
summer. Well-designed shading greatly reduces heat entry, adding
significantly to summer comfort in the home. It can also significantly
reduce the need for, and running costs of, air-conditioning equipment.
The most effective way to keep summer heat out of the house is to
use adequate external shading. North-facing windows can be easily
shaded with fixed shading devices, such as an eaves overhang, horizontal
shade or awning, and pergolas. These shading devices must be designed
so they allow sun entry in winter and totally shade the windows
in summer. Attention should be paid to adequately shading east-
and west-facing windows, while south-facing windows generally do
not need shading.
While important, internal shading such as curtains
and blinds will never be as effective as external shading because
the radiant heat from the sun has already passed through the glass.
To get the best performance from curtains and blinds, you need to
ensure they are opaque and of light colour, to maximise the reflection
of sunlight. Pelmets are a good way to reduce heat loss. Tinted
or reflective glass should be used where it is not desirable to
obstruct the view, and internal shades with a reflective backing
should be used where it is not possible to install external shading
devices. |