March 2018

Flat Roofing: Project Focus
OVERCOMING COMPLEX DETAILS
Total Contractor takes a look at Envirotek’s work on a seven storey commercial scheme in
the centre of Cardiff’s Commercial Enterprise Zone; a project which involved some
interesting challenges...
Aseven storey landmark commercial
scheme in the centre of Cardiff’s
Commercial Enterprise Zone, Number
Three Capital Quarter will provide 77,931ft² of
high quality office space, with a central atrium
and terraces on the 6th and first floors providing
features that will ensure a pleasant and
functional workplace for occupiers.
Designed by architects Morgan 2 Hayman, for
developer JR Smart, the speculative office
building adds to the existing 200,000ft² of office
space already occupied at Capital Quarter,
providing high calibre accommodation for
occupiers.
Prestige & performance
Conveniently, located close to Cardiff’s railway
stations and within easy reach of both the city
centre and Cardiff Bay, Number Three Capital
Quarter is part of a major investment in the city’s
Central Business District. The specification of the
office building not only needs to reflect the
prestige and quality required to attract occupiers
today, but also needs to withstand the test of
time to provide an extended service life for
continued high calibre accommodation in the
future.
As a critical element of the building envelope, the
roof build up had to be aligned to this
specification philosophy and the decision to use a
RubberGard EPDM membrane from Firestone was
driven by the developer.
Gary Foster from JR Smart explained: “We had
used Firestone’s RubberGard EPDM membrane on
previous schemes on the Capital Quarter
development and had been very pleased with how
quickly and easily it could be installed with a neat
Images show Number Three Capital Quarter project. Project details: Total Roof Area: 1,300m² • Products Used: Firestone
RubberGard EPDM waterproofing membrane • Firestone QuickSeam FormFlash • Contractor: Envirotek • Client: JR Smart •
Length of Programme: 2 years
“The team had to
interface the
membrane with
abseiling hooks”
finish. The service life of the roof is very
important for these high calibre office schemes
as it will reduce maintenance requirements and
ensure the building retains its Grade A
performance.
“We’re confident the strength and durability of
RubberGard EPDM will give us a fit and forget
solution, which, as the membrane will be
obscured by the paved overlay, was a vital factor
in the specification.”
The RubberGard EPDM membrane was installed
by Firestone Licensed contractor, Envirotek, on
the main roof area at 7th floor level along with the
terraces at 6th and 1st floor level. The contractor
was involved in the project at design stage to
ensure that sufficient provision was made for
drainage in terms of the number and size of
drainage outlets to maximise roof performance
and avoid any risk of standing water.
Envirotek began the installation by priming the
concrete roof with a bonded vapour control layer.
To further aid drainage to the outlets designed
into the roof, a tapered insulation scheme was
then installed, creating a fall to the drainage
points. This was installed as a two layer
insulation system, with flat insulation board
followed by the tapered board to deliver the
required U-value.
With the insulation in place, the RubberGard EPDM
could be adhered to the roof. Firestone worked with
Envirotek to develop the specification for the
membrane, assisting with wind loading
calculations and optimisation of the membrane
material to support a safe installation process with
high standards of integrity for the finished roof.
44 TC MARCH 2018