Materials you'll need:

• Awnings
• Blinds
• Window locks
• Window mounting air-conditioner
• Plywood
• Foam rubber weather stripping
• Foam rubber off-cut
• Paint
• Caulking compound

Tools you will need:

· Scissors or knife
· Panel pins
· Hammer
· Saw

Many window treatments, as well as being decorative, help insulate the windows. Without any insulation in the form of curtains, awnings, etc. you lose around 14 percent of the heat generated. It literally goes 'out the window,' or more accurately, through the window, by conduction. Heated air penetrates your house in summer by the same means.

Awnings are especially useful on the hot side of your house. As well as throwing a cooling sunshade over windows, making things more pleasant inside, they allow breezes to circulate underneath them to eliminate hot pockets against windows and provide insulation. As well as canvas and aluminium style awnings, you can also buy a sort of external Venetian blind, made of overlapping panels which hang on the outside of the glass These have the advantage of being adjustable to more precisely control the amount of heat and light entering a room.

Anything which helps to prevent loss of heat through windows is helpful The C.S.I.R.O. Building Research Division has determined that white and silver coloured drapes, blinds and Venetians can greatly reduce the amount of solar energy entering a room. For example, 100 percent sun can enter through the unprotected glass. Silver drape or blind, fully closed, can reduce this to 35 percent. White and light coloured Holland blinds, shades and Venetians can also reduce the amount of sun entering by varying amounts.

Other useful products which help to make heating and cooling more efficient include adhesive films which reflect heat rays and shield the room.

Window air conditioners.
Although most often installed in windows, this type of air conditioner is more accurately described as a room air conditioner because it affects one room only, as distinct from a ducted system designed to heat or cool several rooms at one time, These units are usually compact, self-contained fan and re­frigeration units with built-in thermo­stats, Many come with factory-made panels for quick mounting in a window, or simple installation kits to do the same job.

Before selecting an air conditioner, ensure that the wiring in your home can take the extra load. As a precaution, avoid plugging other appliances into the same outlet as the air conditioner.

Most units designed for window mounting will fit into ordinary double hung windows, and many are adaptable for sliding windows. Check with your supplier to ensure the unit you want will fit the planned location. Ideally, the unit should be fitted into a window, which is not in full sunlight for too long, or it should be shaded.

One way to install this type of air conditioner is to simply push the window up, put the unit into place, slide out the accordion-style side panels and close the window on the unit.

However, you can make the unit more efficient by taking a few additional steps. If the installation kit does not provide any, before installing the unit, line the window sill with a strip of self-adhesive foam weather stripping. Put another strip across the top before you close the window. If the unit is to be installed permanently, consider filling in the panels on either side with plywood, painted to match the surrounds This provides a much better seal and will be even more satisfactory if you pipe some caulking compound around the edges of the panels. Lastly, put a wedge of foam rubber into the space between the bottom pane of the window and the top as cold air can sneak in between these panes. When installing an air conditioner in a window, it is a good idea to fit a window lock at the same time. The kind designed to lock a window in a half-open position is ideal.