Window design

● Choose the appropriate size of windows for the orientation and climate. Large windows on the north side of the home will maximise natural heating. But large windows on the south side may cause heat loss.

 

● Wooden frames are attractive, provide good insulation and are eco-friendly if the timber comes from a renewable source. But bear in mind that they can be expensive to buy, especially if custom-made, and require periodical maintenance to ensure the wood does not rot. They are also hard to seal becausethe wood swells and contracts with changes in temperature.

 

● PVC frames are durable, require little maintenance and provide good insulation, but they are made from non-renewable resources and their production is a source of pollution.

 

● Aluminium frames are lightweight and durable. But because aluminium is a good conductor of heat, they can become hot to touch and also require some kind of insulation (a ‘thermal break’) or treatment to make them energy-efficient. In addi- tion, the production of aluminium uses large amounts of energy.

 

● Make windows taller rather than wider.This will let more light in.

 

● Select appropriate glass for your climate. Some types are absorbent,meaning that they allow heat into the house; others are reflective, meaning that they keep heat out.

 

● Consider double-glazing for cold areas. It’s expensive to install, but can cut heat loss by as much as 50 per cent. It can also help block outside noise.

 

● In warm areas, consider fitting insect screens over windows so that you can leave windows open and let cooling breezes in.

 

● Louvres, either in the form of louvred glass panels or louvred shutters, are a useful feature for warm climates, allowing you to admit and direct cooling breezes.