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Energy Savings Trust

The Energy Saving Trust has been set up to help promote companies and products that are energy efficient, that help reduce carbon emissions and save energy.

As an independent government agency, they work with industry experts (such as BFRC the British Fenestration Ratings Council) to establish credible standards and assess which products are the most energy efficient. They then promote the top 20%, in each category, energy efficient light bulbs, loft insulation, cavity wall insulation and windows.

They verify the calculations and projected savings you can make and promote energy savings calculators, for all framing material types. Windows have become far more efficient in the past few years.

Single glazing generally lost approx 5.8 units of heat, double glazing has always been better losing 2.8 units of heat (50% saving), however this was reduced to 2.0 units (1.8 in Scotland) in 2006. This has been reduced again in Oct 2010 to just 1.6 units, that means modern replacement windows are expected to be 73% more efficient than single glazed windows and a 25% improvement from just 4 years ago!

Companies have to have permission to use their blue swing tag logo, and be registered with the Energy Savings Trust. Again this is a voluntary decision to belong to EST, and companies pay registration fees etc.

They like to promote the products more than a service, because an energy efficient window can be poorly installed, thus losing any advantage or savings. So it is the products that get approved, however they have recently introduced an AR scheme, (Authorised Retailers) whereby quality retailers, who install windows, can register with EST and use the logo themselves.


Remember the EST logo is recognition that a product is energy efficient, ie in the top performing 20%

Since October 2010 all companies must offer C rated or better, only companies who offer A or B rated can officially use the EST logo

The Energy Saving Trust have recently improved their web site making it easier to find products and companies, approved by them to use their blue swing tag logo, and through whom Energy Efficient windows can be purchased, www.energysavingtrust.org.uk

The Energy Saving Trust also offers free advice via their UK network of Energy Advice Centres. It’s probably unfair to expect them to know about every energy efficient product in depth, but they should be able to help you with the basics about the energy, fuel and cost savings you can make using the more efficient window products 0800 512012

And remember to look out for Energy Savings Week normally in October each year