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Holger Blum
A synopsis of the symposium lecture given at the STECHY '93 in Prague from 30th November to 2nd December, 1993.

EVERLAST®ROOFSKIN, the long-life roof sealant of the future, has already set new standards in quality and performance. Figure 1,Figure 2 Wherever modern technology and optimum safety are joint requirements for a permanent roof seal, our product, EVERLAST®ROOFSKIN, is the favourite choice
Let me give you just one example:

High-Tech-Roof Sealant
THE FRAUNHOFERINSTITUT, Holzkirchen, selected EVERLAST® ROOFSKIN as the sole product – among all the other materials available – to be used for its 'Technology of the Future' project Prefabricated Houses with Thermal Roof Insulation.

No tar oil, no bitumen, no water; but liquid, ready-to-use one-component roof skin that can be applied all year round, even at sub-zero temperatures, and which crosslinks in any required thickness from 1 to 600 millimetres to form a super elastormer with superior improved characteristics. You could call EVERLAST®ROOFSKIN a space suit for every type of flat roof!

The reason why institutions like the Federal German Army and the Federal Railways

(both having their own test laboratories) and public municipal authorities (with their own team of engineers) repeatedly opt for EVERLAST®ROOFSKIN is, in our opinion, (apart from the economic and technical advantages, such as construction certificates for finished roofs, etc.) due to a scientific factor of major importance for the extremely long life of this roof coating:


Protection mechanism
WHEN the liquid EVERLAST® ROOFSKIN solidifies to form a low cross-linked high performance elastomer with superior low temperature characteristics (< –40° C), a prallel-orientated layer of approx. 1/50 mm aluminium wafers are formed on the open air side of the roof skin in a parallel plane with the liquid surface. This "protective aluminium coat" protects the elastomer underneath it from adverse weather and UV rays, similar to a link chain, and offers almost perfect protection from weathering, as proven by the TÜV test before you.You will find this TÜV -Test in this website under section REPORTS

Up to now, it has not been possible to observe the perfect formation of this "protective aluminium coating" with comparable materials. The so-called aluminised liquid plastics remain "grey" after application, because the aluminium particles are spread more or less irregularly throughout the liquid plastic. The UV radiation from the sun is able to "penetrate" the plastic coating quite deeply and thus destroy it.

As you know, even so-called high-grade roofing felts made of EPDM or other UV-resistant plastics require, according to the manufacturers' instructions, additional protective measures against UV light, such as gravel coating, etc., to guarantee long life.
These additional protective measures against UV light are not necessary if EVERLAST® ROOFSKIN is used.

Successful with problem roofs
EVERLAST® ROOFSKIN has accordingly been officially approved for the repair of so-called polyurethane in situ foam roofs belonging to the housing associations of the German Federal Railways in Munich, for example, as can be seen from Figure 6 in the picture folder. The material had already been pre-tested by the German Federal Railways Testing Authority, Munich, in 1990/91.

In addition, the municipal authorities in in a town of 200.000 population in North Rhine Westphalia , who are mainly responsible for the training of civil engineers in North Rhine Westphalia, decided as early as 1991, after careful examination of the facts, to repair and restore one of their problematic roofs – R's Townhall – with EVERLAST®ROOFSKIN. (Figure7, Figure 8 . As a result of the positive results experienced with EVERLAST®, they will be continuing to use it, even more extensively, in 1994.

Large companies such as Thyssen, AEG and Siemens, for example, have been using EVERLAST®ROOFSKIN for a number of years now for the maintenance and new construction of flat roofs.

As you can also see from the enclosed appendix, the German Federal Post Office, TELEKOM, has specified EVERLAST®ROOFSKIN, and no other material, in its tender specifications for this kind of application throughout Europe.


Excellent gap-bridging performance
THE PRESENT state of technological advance dictates that a coating substance intended to cover cracks and seal the surfaces of buildings, should have an elastomeric consistency. This condition is described in detail in the recently published reference book

"Fugen – Auslegung und Abdichtung"
Dr. Edvard B. Grunau, Siegfried Esser, Klaus Jürgen Jahn.
Institut für Baustofforschung 1992
EXPERT-VERLAG; ISBN 3-8169-0746-6.

According to this, a sealant used on a roof should have a density of between 30 and 60 Shore A at normal room temperature. This condition is met by EVERLAST®ROOFSKIN, (Shore A Hardness of 35 to 55 units ).


Good mechanical properties
ACCORDING to the hardening temperature of EVERLAST®ROOFSKIN, which can be between –15 and +45° C, the tensile strength varies between 2 – 4 N/mm_, and expansion between 300 and 600%. This results from the physio-chemical laws for low cross-linked elastomers in accordance with DIN 7724.

The product of expansion and tensile strength is practically constant, irrespective of temperature, whilst the tensile strength is dependent on the respective hardening temperature. 95% of all samples of EVERLAST®ROOFSKIN taken in situ have been shown, by the way, to have a tensile strength of 2.5 to 3 N/mm_.

EVERLAST® ROOFSKIN– with a tensile strength of >1.5 N/mm at room temperature – also meets the requirements of DAStb (German Committee on RFC Construction) for crack-sealing elastomeric coatings, as also described in:

"Handbuch Betonschutz durch Beschichtungen"
Hans Schuhmann u.a., 1992.
EXPERT-VERLAG; ISBN 3-8169-0577-3.

Whether or not coatings such as this can be walked on, is not only dependent on the hardness, but also on the tear resistance as defined in DIN 53515. EVERLAST® ROOFSKIN can be walked on, since its tear resistance in >10 KN/m.

Serving the customer THE SUCCESS of EVERLAST® throughout Europe can be accounted for by the strict adherence to the following three stipulations:
  1. The material is only applied by specialist companies – there are no over-the-counter sales.

  2. Each roof treated with EVERLAST®ROOFSKIN is given a certificate on acceptance by an independent engineering office, together with a test report

Every company applying EVERLAST®ROOFSKIN is committed to post-inspecting the roof within 33 to40 months after completion of the job, and making good any expansion joints, etc., which were hidden or overseen at the time of original work.
And what's the result?

Everywhere you see an EVERLAST®ROOFSKIN roof, it's perfect – and made to last!


Figure1: Flatroof sealed with liquid elastomer EVERLAST®ROOFSKIN.
Figure2: New flatroof sealed with liquid elastomer EVERLAST®ROOFSKIN
Figure3: EVERLAST®ROOFSKIN coated flatroof at the railway works of BAHN AG in Mecklenburg-Vorpommern . -
Figure4: EVERLAST®ROOFSKIN coated flatroof at the railway works of BAHN AG in Mecklenburg-Vorpommern.
Figure5: Flatroof of railwaystation sealed with EVERLAST®ROOFSKIN .
Figure6: Flatroof with sprayed-on insulation polyurea layer, sealed and restored with EVERLAST®ROOFSKIN.
Figure7: The flatroof of the townhall before it was sealed and coated with EVERLAST®ROOFSKIN.

Figure8: Flatroof of the town hall after being restored and sealed with EVERLAST®ROOFSKIN.

References 1] "Flachdachrichtlinien" DDV-Verlag, Köln 1990
[2]"Fugen – Auslegung und Abdichtung"
Dr. Edvard B. Grunau, Siegfried Esser, Klaus Jürgen Jahn.
Institut für Baustofforschung 1992
EXPERT-VERLAG; ISBN 3-8169-0746-6.
3] "Handbuch Betonschutz durch Beschichtungen"
Hans Schuhmann u.a., 1992.
EXPERT-VERLAG; ISBN 3-8169-0577-3.