CPD Specifier May 2015 issue September 2015 | Page 25

Roofing

Kemperol protects and preserves
Tectons at Dudley Zoo

As roofing projects go, they don’t come much more unusual than a bear
ravine at a zoo! At Dudley Zoological Gardens (DZG) it’s not just the
buildings’ use that made a recent Kemper System project so remarkable,
but the heritage of the structures in question too.

One of the main priorities of the refurbishment programme is to protect the
structures from water and environmental damage due to rainfall, which
led to specification of Kemper System’s Kemperol cold liquid-applied
waterproofing systems.

TECTON HERITAGE

IMPACT ON ENTRANCE

The Tecton buildings at DZG - 12 of them in total - were designed by
Bethold Lubetkin and his Tecton practice. They are the world’s largest
single collection of Tecton buildings and some of the few remaining UK
examples of this innovative architectural movement from the 1930’s and
1940’s.

The entrance canopy consists of five horizontal ‘S’ shapes, each
overlapping the one before to create a wave like ripple that announces
the word ‘ZOO’ in big white letters below.
The curved shapes catch rainfall, which makes the structure vulnerable
to standing water and the damage it can cause. The Kemperol 2K-PUR
waterproofing system was ideal as it is impervious to standing water and
able to follow the exact contours of each curve to protect the structure.

Tecton was a radical architectural movement that used pre-stressed
concrete to create striking curved structures that enabled the architects to
work with the challenging slopes and underground limestone caverns on
the site.

BEAR RAVINE

Over the years, trends in zoo best practice have meant that some of the
structures are no longer in use as viewing enclosures. Time has also
taken its toll on their wear and tear too: DZG’s Tectons were put on the
World Monuments Fund’s watch list of world class buildings threatened by
neglect, demolition or disaster in 2010.

The design of the Bear Ravine includes a central bear pit with a raised
walkway and viewing platform - accessed by a set of concrete stairs that also forms a partial roof to the largely open building. There is also a
viewing pier that extends out at a right angle beneath the main walkway.
Explains Stuart Hicks from Kemper System: “The Kemperol waterproofing
products from Kemper System can be applied to the exact contours of the
existing prepared concrete substrates in a single process. They cure to
form a monolithic membrane ѡ