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Choose tested windows

- because it is important to know what you are getting

On February the 1st 2010 new rules for window marking were introduced. This means that all manufacturers for the European market must mark their windows with the well-established CE mark. In the UK the CE mark is not mandatory but documentation on compliance with it is. CE marking gives manufacturers the opportunity to document the quality of their windows and how resistant they are to extreme weather conditions. These tests are voluntary, but for Rationel the decision to test was easy - because it is important to know what you are getting.

Rationel has very high quality demands and that is why Rationel was one of the first manufacturers to be fully accredited with the CE mark on all our windows and doors. With the new rules, there is now an external evaluation that will make it easier for our customers to compare Rationel with other window manufacturers.

How to benefit from the CE mark?

With the new rules for testing in place, you can get an idea of the impacts and conditions that our windows can withstand. This way you can be confident that Rationel windows can provide protection from the extreme weather.

See the test results here.

Rationel CE data are updated continuously. To find the tag data that are relevant to your Rationel products, you need to know when they are produced.

You can find the production date on your order confirmation. If you do not have the order confirmation nearby, you can see the date printed on the spacer in your glass. See here.

>>  Click here for CE-data valid for the period 15.06.2012 - 01.07.2013

>>  Click here for CE-data valid for the period 07.11.2007 - 14.06.2012


At Rationel we make high demands on the quality of our windows and doors. Our products must not only meet the demands of the window industry but also achieve results at the high end of the scale. Our products have passed the tests with the following classes: Air 4 and wind C4.

Real life tests

The tests are realistic and evaluate windows and doors in critical areas that most people can relate to.

Testing for air-tightness

This test simulates extreme conditions up to 69 mph (31 m/s)(600 Pa), which is equivalent to a violent storm of force 11.

Air passing the unit


Max pressure when testing

Air passing measured in m3/m2 area per hour

0 Not tested Not tested
1 150 50
2 300 27
3 600 9
4 600 3

Italics = Guidelines from VinduesIndustrien    Bold = Rationel test result

Air passing between sash and frame


Max pressure when testing

Air passing measured in m3/m2 areal per hour

0 Not tested Not tested
1 150 12,50
2 300 6,75
3 600 2,25
4 600 0,75

Italics = Guidelines from VinduesIndustrien   Bold = Rationel test results

Testing for sound reduction

Windows are tested in a special laboratory, where they are exposed to sound waves. The output is a curve showing the sound reduction as a function of the frequency. The sound reduction of the window is given as Rw(C;Ctr).

Rw is the average sound reduction of the window and is given as dB. Because this test does not take especially high/low and monotonous sounds into consideration two additional values are given - C and Ctr. C is used where there is music with high tones or where there are traffic noises like horns and other sudden high sounds. Ctr is for sounds such as speach, uniform music and monotonous noise from trains and traffic. These two values must be subtracted from the Rw value to find the sound reduction that matches the given situation. 

Testing for resistance to wind load

This test is not about water penetration, but about the robustness of the window itself. With blasts of wind up to 116 mph (52 m/s), the test simulates conditions so extreme that the Beaufort scale does not have a word for it (1600 Pa). The windows are evaluated on two criteria: deflection (how much the window flexes) and partly for permanent deformations.

Class Max deflection Class Wind force Pa
A <1/150 0  -
B <1/200 1 400
C <1/300 2 800
Blank.jpg Blank.jpg 3 1200
Blank.jpg Blank.jpg 4 1600
Blank.jpg Blank.jpg 5 2000

Italics = Guidelines from VinduesIndustrien   Bold = Rationel test result

Rationel has achieved excellent test results compared to the guidelines laid down by VinduesIndustrien. Remember that Rationel also meets requirements for the existing building regulation standards.

Please note that a small range of special units cannot be tested and these units are classified by CE as no performance determined (npd). All the other test results can be seen here.

Declaration of conformity Rationel AURAPLUS and Rationel AURA windows

Declaration of conformity Rationel AURAPLUS and Rationel AURA doors

Declaration of conformity PATUS and PATUS+

Declaration of conformity DOMUS and ALDUS 

Here you can read about:


  • Fully tested windows

  • Realistic tests

  • Noise testing

  • Air testing

  • Wind testing

  • Rationel Windows Ltd.
  • 7 Avonbury Business Park
  • Bicester, OX26 2UA
  • United Kingdom
  • Phone +44 1869 248 181
  • Legal disclaimer