Energy Efficiency


Energy efficiency is an essential ingredient for Windows and Doors, traditionally the weakest point in a home’s thermal insulation. Now is the corner stone and driving force to everything we do!
In the UK, thermal efficiency isn’t just a nice selling point, it is a legal requirement on all new installations, and when designing and manufacturing our products we always make it a priority. Our frames are designed to a high grade of efficiency and when combined with energy-rated glazing, they exceed all current building regulations for replacement windows or new fittings.

  1. How is energy efficiency measured?
  2. Thermal transmittance is about measuring how much heat escapes through any given material; it is measured by the number of watts escaping through a square metre of glass for every degree of heat on the American “Kelvin” scale. This is called the U-value. In essence the lower the U-value the better, as less heat is escaping; so a typical single pane window has a U-value of about 6, standard double glazing is around 3.
  3. What are the legal requirements for thermal efficiency?
  4. Building Regulations include a Document L which outlines thermal efficiency requirements. In its most basic form the legislation requires U-values around 2, but they do vary depending on the type of glazing you are using and the design of the model.
  5. How much money does it actually save getting better windows?
  6. Order our frames with high rated glazing and you can cut heat loss through the windows by a half; that adds up to £135 a year off the average UK heating bill and 720kg less carbon dioxide from the atmosphere. If everyone in the UK with old windows replaced them with new, the country would save £700m on heating bills every year!
  7. It isn’t just about the products …
  8. In practice even the best windows or doors can still let unacceptable amounts of heat escape if they are poorly fitted, so it really pays in all ways to get a professional installation from our expert team of fitters. Whether it’s a new door, a full set of windows or a beautiful new conservatory in your back garden one call to us gets the complete job done to the highest standard.


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