Mr Skill

When choosing new or replacement windows for our properties, the two things most frequently considered are appearance and price. If, however, a London window fitter could show you the potential energy loss as a style or a discount, we may reconsider our priorities. According to the Energy Savings Trust, replacing single glazed windows with energy efficient double glazing in London would save the average homeowner £130.00 per year. When you consider that a good quality double glazing unit should last 10 years or more – that represents a considerable saving!

Windows lose heat in four ways.

Conduction – The direct transfer of heat through the windows to the outdoors.

Radiation – The movement of heat as infra-red energy through the glass

Convection – When heat is cooled by the lower temperature of the glass

Air leakage – When heat is lost through cracks in frames and ill-fitting glass

The rate at which a window loses heat through the combination of the four is called its U-value, and the lower the U-value, the warmer you will be in the winter, the richer you will be when you receive your fuel bills and the happier you will be about your property’s CO2 emissions – about 18% of your home´s carbon footprint goes out the window.

There are other benefits of changing your existing windows to energy efficient ones too. Your house will be quieter because as well as keeping heat in, energy efficient windows keep unwanted noise out. Furthermore, energy efficient glazing reduces condensation build-up on the inside of windows.

How do Energy Efficient Windows Work?

It is not so much the windows that are energy efficient, but the panes of glass and what goes between them. Double glazing has two layers of glass with a gap of around 16mm between them. There’s also the option of triple glazing, which has three layers of glass.

The most energy efficient glass for double glazing is low emissivity (Low-E) glass. This often has an unnoticeable coating of metal oxide, normally on one of the internal panes. This makes the glass reflective, keeping heat in and the home warmer in the winter and reflecting heat back in the summer, making the home cooler. Very efficient windows might also use gases like argon, xenon or krypton in the gap between the 2 sheets of glass.

Installing Energy Efficient Windows

When you think about replacement glazing, you need to make sure your windows are installed correctly and comply with all the relevant regulations. For new energy efficient window installations (in extensions or where there was no window before) you will need to apply for Building Control approval before installing the windows.

If you are using a professional window fitter in London to do the installation, he should be registered with a competent persons scheme and register the installation through Local Authority Building Control. Replacing like-for-like window installations does not need approval, but you (or your London window fitter) still have to comply with Building Regulations Part N.

Grants are available from many London councils if you are considering installing energy efficient windows into a property which has been left vacant for a period of time or your improvement qualifies for a Home Repair Assistance Grant. Installing energy efficient windows as part of a property conversion for a disabled person will also qualify for a local council grant.

Whether you need help in selecting your windows or installing them, getting a quote from a window fitter in London could not be easier. Simply use the “Post-a-Job” facility at the top of the page to alert local window fitters in London to your requirements, or browse through our Tradesmen´s Directory to find a local window fitter in your area.