energy saving composite windows


Ensuring you fit energy efficient composite windows should be high on your list of priorities, whether you’re replacing existing windows and doors or designing a new house or building.

(Article accurate at the time of publishing).


According to the Energy Saving Trust website*, just by installing double-glazing to windows in an entirely single-glazed property you could save up to £115 per year.

Heat loss is measured by the thermal transmittance characteristics of a material or U-value. It is expressed in Watts/m²Kelvin which is a measurement of the amount of energy conducted per square metre multiplied by the temperature difference on either side of the material.  The lower the U-value, the greater its thermal insulation properties.

Benefits of fitting energy efficient windows are:

  • Create a comfortable home environment – energy efficient glazing reduces heat loss through windows and means fewer draughts.
  • A peaceful home – while they keep the heat in, energy efficient windows also insulate your home against external noise, such as traffic, railways or if your home is on a flight path.
  • Reduced condensation – energy efficient glazing reduces the build up of condensation on the inside of windows, removing the risk of a damp home.

Read more about how composite windows can help reduce condensation in your home in our advice centre article: HOW TO REDUCE WINDOW CONDENSATION

composite windows how energy escapes from your home
energy saving composite windows


With Westcoast composite windows and doors the aluminium and timber are bonded to make a truly composite frame and sash.  The timber element acts as a thermal break to ensure very high levels of insulation, and seals housed into the grooves within the sash create exceptional air and weather tightness.

You can also select from almost all glass types available on the market today. For all the contemporary demands of thermal insulation, sound attenuation, solar control, safety or security. Double or triple glazing.

Our triple-glazed Design Series has U-values as low as 1.0 W/m2 for opening windows and down to 0.9 W/mfor fixed windows, making them our most energy efficient composite windows.

Our Design range offers a contemporary feel, suited to modern architecture with a deeper glass unit creating a minimal step between outer glass and frame for maximum light, a flush finish and simple, elegant lines.

  • Available in outward opening windows and doors, and sliding doors, in 48mm triple glazing.
  • The deeper glass unit removes the need for a step between frame and glass and creates a flush finish and clean lines.
  • Free rein to specify the size and shape of your windows.

Read more about the construction of our windows in MADE IN SWEDEN.


Warm Edge Technology refers to the edge construction of the window and uses a spacer that is warmer than traditional cold edge aluminium spacers. Therefore it conducts less heat or cold than traditional windows and standard construction glazed units.

Westcoast windows and doors are factory double or triple glazed with 28mm, 36mm or 48mm dual sealed units constructed to EN 1279-2:2002, incorporating the latest ‘warm edge’ technology, single or multiple low emissivity coated glass and argon gas filling as standard.

A groove built in to the aluminium extrusion extends around the entire perimeter of the window allows the window to be cleanly sealed on closure. The aluminium extrusions are specially designed to allow the window frame to be fully drained and ventilated, preventing harmful moisture and rot from damaging the timber.

By using our high performance windows and doors, you can create an energy efficient home and a pleasant living space, whilst helping to reduce heating costs and also lessen your impact on the environment.

Find out how Westcoast composite windows can help you save on energy bills – contact our skilled UK-based team on 01359 241944 or email:

energy saving composite windows

For more information about Westcoast Swedish aluminium timber composite windows visit our MADE IN SWEDEN and STYLES & OPTIONS pages.

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