PITCHED ROOFING
Roofing today: an evolution
Karl Moxon, bid manager at Prater, discusses recent developments in the roofing sector and looks at what
these trends are likely to mean for the future
Due to the complexity of modern
designs, the industry has
innovated and embraced
newbuild processes, with both
new and existing materials being used in
unique and challenging ways. This interdependence
between complexity and
innovation has accelerated the evolution
of roofing to become one of the most
carefully considered areas of a build
during the conceptual and design stages.
The range of materials used for
roofing solutions has grown. For example,
while metal standing seam roofing
has traditionally been used in industrial
and agricultural environments,
we have seen more of it
installed on high-profile projects
such as the Olympic Velodrome
– a project where Prater installed
13,000m2 of aluminium standing
seam supported by a cable net
roof structure, and the redevelopment
of London Bridge
Station.
We are also seeing building
designs become increasingly
complex, incorporating geometric
roofing features which would
have been unthinkable two
decades ago. Digital engineering
and the ability to effectively
model these structures using 3D
design and Building Information Modelling
(BIM), has meant the concept can
be delivered on time, within budget,
and more importantly, with minimised
risk. To highlight this process,
our supply chain partner BEMO can
conduct a cloud survey of the structure
from a geometric model at its facility in
Germany. This 3D scan can assess the
structural on-site requirements of the
building, and translate this into an offsite
construction model that defines the
optimal position for the mounts. From
this, the exact design of each of the
components along with the bespoke
forming of each sheet is then manufactured
specifically to fit the structure.
Another key trend that we are seeing
increasingly in the industry is the
use of off-site manufacturing – particularly
amongst building envelope
contractors.
On many large-scale projects, offsite
manufacturing is now a key driver
of both the client and professional
team where previously this was an
aspiration, now this is a fundamental
requirement of the vision in delivering
high-quality projects – many examples
of this are seeing
the benefits in the
infrastructure and
aviation sectors.
Off-site manufacturing
has
formed an important
part of
Prater’s work on
the redevelopment
of London Bridge
Station. For this
redevelopment,
complex requirements, restricted site
access and tight project timescales
meant that an on-site solution wasn’t
feasible. As such, the structural steel
roof cassettes were manufactured in
partnership with our supply chain, delivered
to site and installed with all the
required M&E services pre-installed
into the cassettes.
With energy efficiency remaining
high on successive governments’ agendas,
Vacuum Insulation Panels (VIP)
are increasingly being used to provide
higher levels of thermal efficiency, as
well as solve issues with restrictive
critical dimensions at interfaces, whilst
ensuring compliance with Building
Regulations. These panels – which seal
the insulation within an airtight unit
– have a thermal performance that is
up to five times better than standard
insulation options, and is a technology
that Prater is working closely with its
supply chain partner Radmat in providing
bespoke solutions to projects.
Green and bio-diverse roofs have
also become an increasingly popular
choice among specifiers. Commonly,
a condition of planning permission
on specific types of projects where the
building must blend into the environment,
living roofs are now a key consideration
for any new development. In
addition, we are also seeing more blue
roofs being specified in response to the
continuing use of impervious materials
in major cities and developments.
These systems prevent flooding by
managing the flow of rainwater from
buildings into drainage systems.
Furthermore, in urban environments
where space is at a premium, architects
are increasingly looking to ‘go the extra
mile’ in terms of rooftop design.
For both residential and commercial
buildings, a green roof can provide an
outside space to enjoy. This has been
taken a step further in recent years
with designs utilising rooftop spaces
for features such as swimming pools,
running tracks and relaxation areas.
The added value these features provide
help to maximise the return on investment
for the developers and building
owners as well as help support
corporate social responsibility goals.
For the roofing sector, factors such
as aesthetics, sustainability and the
benefits to the building occupants
and owners, as well as the environment,
have driven specifiers to look
at how new or familiar materials can
be used in innovative ways. Advances
in digital engineering and modelling
technology, as well as the build process
have made complex designs achievable
even where there are restrictions in
terms of project requirements or site
conditions.
w www.prater.co.uk
Top image:
Bringing
nature and
green spaces
closer to
building
occupants was
a core concept
in the design
of Alder Hey
Children’s NHS
Foundation
Trust in
Liverpool.
Bottom image:
London Bridge
Station roof,
which Prater
worked on
90 www.rcimag.co.uk November 2018
/www.prater.co.uk
/www.rcimag.co.uk
