EPDM Rubber Shrink
Unless Europe has some miracle EPDM I don’t know about after 4 decades as a journeyman roofer; the walls, roof and chimney flashing will all fail within a decade.
The rubber will shrink and pull off the walls, a product that Firestone, Versico aka Goodyear and Carlisle EPDM roofs mandate at walls is called RUSS strip and you didn’t install it.
Preventing EPDM Rubber Shrink
RUSS is a 6 inch wide 60 mil roll of heavily reinforced EPDM that sits flush at the break in the walls and deck. It gets screwed and plated every 8 inches, then your field sheet of rubber is glued directly to the RUSS stripping before being rolled up the wall as flashing.
RUSS completely eliminates the natural shrinkage of the field sheets from pulling the rubber off the walls, in USA RUSS is also used around all penetrations such as soil pipes and such.
Comments (2)
We use EPDM rubber roofing from Firestone, they ask that RUSS strips be used only when large expanses of flat roofing is laid. The shrink back of EPDM rubber has been known for many years. It was addressed by the manufacturers back in the late 70s and now the shrink back is much less. Also, the old way of laying EPDM rubber was to not fix it down but to keep it in place with ballast. This enabled shrink back or contraction o the complete area of the roofing material. Today the complete sheet is glued down thus stopping expansion, thus minimising the amount of contraction. The roof above is 6m in width, if we assumed a massive shrink back of say 1mm per meter we are talking about 3mm each end. I’ve now been working with EPDM rubber for over 12 years the old EPDM roof I’ve been on to inspect was in London Euston over a hotel the roof was over 400 m², 30 years old and in perfect condition.
At the time we did the above roof Firestone recommend using RUSS strips only when a roof area was over 100 m²
Hi mate what is the best way to vent the front and back of my skylight on a cold flat roof regards Jamie