Windows were traditionally made of wood, and it is still popular because it is so versatile. Softwood windows need to be protected by paint or a natural wood finish, and regularly maintained.
Double-glazed, vinyl windows offer excellent heat and sound insulation. Old windows are often replaced throughout a house by new vinyl windows. In addition to white, other finishes are available, such as wood-grain. Vinyl requires little maintenance.
Where maximum light is required, aluminum windows can be an excellent option-the strength of aluminum means a thin frame can support a large expanse of glass. Double-glazing may be required by building regulations to reduce heat loss.