EPDM Lasts – this single ply is hard to beat

Jul 19, 2017 in Case Studies, ClassicBond, DuoPly, General, RubberBond, SureEdge, SureWeld
EPDM Lasts – this single ply is hard to beat

Over the last 45 years, Carlisle EPDM has gained industry wide acceptance and respect by providing both immediate and long term roofing solutions. During that time, EPDM has also racked up some impressive figures in the low sloping market.

As of last year, roofing contractors had installed over 500,000 warranted EPDM roof systems, representing over 1858 million square metres. No other single ply system comes close.

On the new construction side, more than 92 million square metres are specified annually in the U.S. alone. According to the EPDM Roofing Association, black EPDM roofs account for more than 52% of roofing installations in the northern U.S., zones with conditions comparable with the UK.

Weatherability is the key reason why more EPDM roofs continue to perform in the existing inventory than any other single ply membrane. In addition to excellent weathering characteristics, EPDM is a low maintenance roofing system that offers superior wind, hail and fire resistance.

Ask the experts

Wilbur Kline ranked in the top 100 specifiers by McGraw-Hill is also a firm believer in the long term performance of EPDM.

“I can’t remember any kind of problem with any project in which I used EPDM membrane”, says Kline. “I just kept specifying EPDM because the performance was consistent.

What makes EPDM such an outstanding roofing system? Besides its legendary weatherability, EPDM is dimensionally stable, yet expands and contracts with the building movement in a variety of climates.

EPDM is virtually immune to ozone, UV radiation and cold cracking. The material does not rely on plasticizers for its flexibility, so there’s no danger of the material becoming brittle from plasticizer loss down the road.

Seam tapes and accessories

There’s an old adage in the roofing industry that says a single ply roof is only as good as its seams. While early EPDM systems were almost bullet proof when it came to weather resistance, the first generation of products relied on liquid adhesive for lap seaming.

Though acceptable at the time industry professionals knew that a more reliable method would be needed in order to make the system a viable, long term roofing solution.

“From a weatherability standpoint mil for mil EPDM has proven to be one of the most cost effective membranes available today” says Rene Dupuis, president of Structural Research Inc.

Dupuis has probably studied more EPDM membranes – both in the laboratory and on the roof -than any other independent roofing researcher over the last 30 years. Dupuis is also known for his objectivity and honesty when evaluating roofing systems.

“It’s remarkable in hind sight that EPDM started out with one of the more vulnerable lap systems” he says. “However, the industry certainly did not rest till a true high performance tape system was perfected.”

Walt Rossiter, technical director for the Roof Consultants Institute and former research chemist at the National Bureau of Standards agrees. “EPDM seam performance is really a non-issue, it’s simply not discussed any more”, Rossiter says. “The steps the industry has taken in terms of seam tapes and pre-formed accessories has been fabulous.”

“To be able to take a pre-formed pipe boot with a taped flange and slip it over a pipe penetration is amazing for two reasons” saysRossiter. “It saves on labour, but more importantly, it eliminates stretching and bending of the membrane, along with the use of liquid adhesives.”

Rossiter should know, as he helped author a landmark NIST study on the performance of tape bonded EPDM seams in 1997.

“We spent well over three years analysing the performance of taped EPDM seams”, recalls Rossiter. “One of the things we discovered was that the strength of a seam made in a laboratory and in the field were statistically comparable. That was not the case for the old butyl based liquid adhesives”.

Speak to a member of our team for help and advice on the best solution for your flat roofing project; call us on 01494 448792 or email us at enq@flex-r.co.uk