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insulation sound proofing draught proofing stop condensation
elegant secondary glazing
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Extraglaze Explained
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  • 2 weeks ago
    ratings 4
    Excellent result
    Service rating : Extraglaze offer a great service and made a wonderful job of installing secondary glazing on our stained glass windows. They were very patient with me going backwards and forwards to ask for different variations on the quote. However, despite having given as much information in...
  • 2 weeks ago
    ratings 5
    Service rating : Have used extraglaze several times great service as always !!!
    Product : excellent service and support
  • 3 weeks ago
    ratings 5
    Service rating : Excellent level of communication, explanation and general contact. Nic was always there to discuss, answer questions or clarify any query.
    Product : The panels are excellent, and the magnetic fixings have worked a treat. They are virtually invisible and have cut our condensation...
    Dr Martin Toms, Herefordshire
  • 3 weeks ago
    ratings 5
    Outstanding product, 5 star service
    Service rating : Nic Irvine provided fantastic service from start to finish. He was happy to spend time on the phone answering numerous questions about the product initially. He then took time doing a detailed survey of our windows, established recommendation from someone I was able to visit, and...
    Rebecca Burrell
  • 4 weeks ago
    ratings 4
    Service rating : Delivered what and when was required
    Product : same as previously ordered
    George Tillier

Extreme Adhesive Test



We wanted to prove to ourselves our adhesive is as good as if not the best!

Proven to improve


coventry university logo bre logo


The Building Research Establishment and Coventry University complete tests of the Extraglaze system
Soundproofing and thermal test results...


Recommended for Listed Buildings


Telford and Wrekin Conservation Department encourage the use of secondary glazing, where possible, to increase thermal efficiency.


Proven to improve


Extraglaze tested at Coventry University and at the Building Research Establishment

  coventry university logo

Coventry University – Thermal insulation tests

In April 2014 we received confirmation that Extraglaze is a scientifically proven thermal insulation solution that beats a typical aluminium framed alternative.
outside chamber sm

Outside the University's Environmental Chamber.
Below - Extraglaze put to the test in the Environmental Chamber

inside chamber sm

The university's Sustainable Buildings Future project used their Environmental Chamber to compare Extraglaze with an aluminium-framed, glass-pane secondary glazing system...
...Extraglaze came out the clear leader.

arrowpichigh tinyWith both systems tested on a single glazed sash window the U-value for Extraglazeproved 11% better (2.28W/m²) than the alternative product.

arrowpichigh tinyWe already knew that Extraglaze would be a better solution to deal with condensation, and the tests confirmed it. In a humid room test (60%RH), with below zero temperatures outside (-5 and -10ºC) Extraglaze was an impressive 78% better.

bre logo BRE – Sound insulation tests
In July 2013 a large timber framed window (1.3m² of visible glass) was installed in the Building Research Establishment's (BRE) Horizontal Transmission Suite, and tested against an aluminium framed glass secondary glazing system. A wide range of tests were made, to see how secondary glazing could not only improve a single glazed window but even a double glazed window.
b9 acoustic lab sm

Extraglaze put to the test in the Horizontal Transmission Suite
inside b9 sm

To summarise the results both systems were rated "good" as a sound insulator for noise problems. We learned in particular that smaller panels do best, being more rigid, and the larger the gap, between the original window glass and the Extraglaze, the better. What surprised us most was that it didn't seem to make much difference whether the original window was double glazed or single glazed.

Proof in practice
In January 2014 Extraglaze was installed onto brand new triple glazed UPVC bay windows in a home by a main road. The triple glazing had been installed to cut the road noise but had proven ineffective. However, with the addition of Extraglaze road noise was almost completely eliminated.
extraglaze soundproofing

And news from customers...

We have an ever increasing number of fabulous testimonies from our customers, which can be seen in the many reviews they have left on Feefo. It is clear that our customers enjoy their homes much more now than they did before Extraglaze was installed, being much warmer and much quieter.

For more information about Extraglaze please view the information in this site or contact us on the number above.

If you are an engineer or architect please contact us to discuss the results of tests in more detail.


Help & Guides

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How to stop condensation


For sash windows
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For casement windows
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Easy Open System
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