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Rheinisch-Westfälischer Technischer Überwachungs-Verein e.V. ; Office: Essen (RWTÜV)

Commission-N0. 27 3528/01

Digest from : Report on the Artificial Weathering of "Everlast" Roofskin /Date 18.09.92


1. Procedure and assignment
The applicant, manufactures and distributes a roofing seal based on polyurethane elastomer. In order to test its weather resistance, RWTÜV were given samples of this roof skin, which had been applied as an approx. 1,5 mm coating to a V13 fibreglas/bitumen roofing felt strip to DIN 52 143 specifications.


2. Tests A section of the sample was artificially weathered on a turning frame in a 450 xeno testing unit for 10,000 hours (= 18,600 MJ/m2) with a cyclus of 18/102, 63 degrees Celsius black standard and at 60% humidity. This corresponds to test conditions in accordance with DIN 53 389-1B-X standards.

In order to assess the changes in the sample, and in addition to conducting a visual test, the fastness index was determined in accordance with the DIN 54001 grey scale, as well as the reflectometer index in accordance with DIN 67 530, at a beam angle of 60 degrees,

The test results after 1000, 4000 and 10,000 hours of weathering are presented in Table1

Within the scope of the visual examination it was established that the weathering of the roof skin had produced no cracks, swelling or deformation.The sample showed no noticable damage after 10,000 hours.

3. Summary and evaluation After a slight initial change in colour of the sample (up to approx. 500 hours) no change occured for a long time.Towards the end of the weathering test, the sample recovered, i.e. the colour change reverted.This could possibly be due to the migration of particles of the bitumen base into the roof skin.
  • The same applies to the reflection rating of the sample surface. After a sharp decline in the first test phase (condition on delivery: 26.8 ; after 1000 hours: 4,2) the reflector index increased again towards the end of the weathering test.

  • Changes in surface quality (cracks, swelling, etc.) were not established throughout the whole duration of the test.

  • To summarize, the results of the weathering test on "EVERLAST" Roof Skin can be assessed as positive regarding the properties tested. The weathering test, which lasted 10,000 hours, did not cause any serious deterioration of the properties of the roof skin (see Picture1).

Picture 1: Bitumen felt strip samples coated with EVERLAST®Roofskin before (left) and after (right) 10, 000 hours weathering.

Table 1: The test results after 1000, 4000 and 10,000 hours of artificial weathering

Rheinisch-Westfälischer Technischer Überwachungs-Verein e.V. ( RWTÜV )
Central Materials and Processing Section
Kurfürstenstrasse 58
45138 Essen

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