Refurb Projects April 2017

PROJECT
SureClad ® provides Lightweight Engineered
Stone solution in Edinburgh
Brian Newell Founder and Chief Executive at ventilated façade specialist,
Shackerley, discusses the SureClad® engineered stone façade specification for
The University of Edinburgh’s Appleton Tower.
Accredited as a World
Heritage Site by Unesco in
1995, Edinburgh has more
than its fair share of
heritage buildings. The city’s
architectural legacy reaches much
further than the traditional sand
stone edifices that dominate
Princess Street, however, and
includes important examples of Post
War Scottish architecture.
One such building is Appleton
Tower, an eight storey facility that
currently serves as part of the
University of Edinburgh’s School of
Informatics. Constructed as part of
the University’s George Square
development in the 1960s, the Alan
Reiach, Eric Hall and Partnersdesigned
building has been
controversial since it was first built.
Indeed, opposition to the stark
modernism of the George Square
scheme was such that some of the
proposed buildings were never
constructed. It continues to divide
opinion today: Historic Scotland
proposed that it should be listed in
2005, while in the same year it was
nominated as an eyesore for
Channel 4’s ‘Demolition’ programme.
Much of the building’s interior
was refurbished in 2006 and the
latest scheme to update and
upgrade the building has seen a
complete renewal of the building
envelope, along with construction of
an additional storey at roof level
and a new feature entrance at
ground floor level. The building’s
ceramic tile faced, pre-cast concrete
and aluminium frame glazed façades
have been stripped out and replaced
with Shackerley’s SureClad®
engineered stone ventilated façade
system
SLIMLINE AND LIGHTWEIGHT
The new cladding was specified by
Edinburgh-based LDN Architects in
conjunction with Buro Happold
Engineering.
As Ross Crichton from LDN
explains: “We specified Shackerley’s
SureClad® engineered stone system
to reference the building’s original
aesthetic and complement other
George Square developments, while
upgrading it to create a sleek,
contemporary look.
“As part of the building envelope
upgrade, which included replacing
the original single glazing, the
SureClad® system also formed part
of a strategy to improve the thermal
performance, bringing the structure
into line with current building
regulations.”
Specification of a SureClad®
engineered stone ventilated façade
system also offered a cost-effective
route to providing an aesthetic that
echoed the appearance of the
façade of the University Informatics
Forum directly opposite. Meanwhile,
it satisfied the loading capabilities
on the remaining concrete structure
and enabled full insulation of the
building within a ventilated façade.
Several approaches to renewing
the façades were considered and
LDN Architects worked closely with
structural and façade engineers,
Buro Happold, to identify a system
that would address the limited
loading capabilities of the structure
while delivering the required
aesthetic. A SureClad® system
comprising engineered stone facade
panels cut to 1363 x 1200mm and
1080 x 2123mm formats, with a
thickness of just 15mm, proved the
ideal response to these
requirements.
Because engineered stone does
not have the inhrerent flaws and
defects of natural stone in its
quarried state it is a hard and strong
material. This means that
Shackerley’s SureClad® engineered
stone panels can be manufactured
with a more uniform finish and a far
slimmer profile, resulting in much
lighter panels.
LDN specified a white honed
engineered stone with a very subtle
fleck from the wide SureClad® range.
The result is a building that has an
evolving aesthetic depending on
your vantage point.
Ross adds: “From a distance, the
façade appears to be a clean, almost
white monolithic surface, which
complements the edifices of the
adjacent university buildings. On
approaching the building, the finish
of the engineered stone panels
comes further into focus, revealing
the subtle variation in surface
texture”.
INSTALLATION-READY
While tests to the concrete
building envelope revealed that it
was still structurally sound, it was
nevertheless coming to the end of
its design life. Furthermore, there
were problems with the single
glazed windows. Some of the
opening elements were failing and
the glazing was contributing to the
building’s poor energy
performance.
As a result, the scope of the
project included removing the tiles,
stripping out the pre-cast concrete
façades and replacing the singleglazed
windows on the North and
South elevations. An elaborate
working platform was erected
around the building to ensure the
required functions within the
20 APRIL 2017, REFURBISHMENT PROJECTS