CPD Specifier May 2015 issue January 2014 | Page 13
Roofs
Belzona weatherproofing
solutions to roof problem areas
Roofs commonly suffer from damage caused by
movement during freeze-thaw cycles, physical
damage, rain and adverse weather conditions. Flat
roofs in particular can deteriorate quickly due to
standing rainwater, which in turn leads to leaks at
the joints and seams, flashings, gutters or glazing
bars.
Belzona 3111 (Flexible Membrane) is a coating
that is brush applied in conjunction with Belzona
9311 (Reinforcement Sheet), which enables
it to encapsulate many complex contours or
substrates. In 1974, a deteriorating papier-mache
dome of the UK observatory needed urgent
attention. A fully reinforced Belzona system was
used to fully encapsulate the dome. To ensure
complete weatherproofing for future years a single
layer of Belzona 3111 (Flexible Membrane) was
subsequently applied in 1988. This application
was recently inspected and still gound to be in
perfect condition.
Replacement can be very costly, conventional
roof repairs do not offer long-term protection
and involve either hot work, which is unsafe and
disruptive, or the use of hazardous solvent-based
materials. Deteriorating roofs can compromise the
building’s structural integrity, restoration of which
will be a time consuming, costly exercise.
Belzona offers a cost effective solution to various
roof problem areas that can be easily applied to
numerous substrates, such as asphalt, felt, lead,
glass, stonework and aluminium amongst others.
Belzona 3111 (Flexible Membrane) System is a
liquid applied single component , solvent free,
microporous coating for the long-term repair and
protection of all types of roofs.
Once cured it remains flexible in service allowing
roof structure to move but remain water-tight.
The system will have 100% crosswise and 20%
lengthwise elongation - BS2782 test. This versatile
material provides outstanding weather proofing
and waterproofing properties with excellent
protection against ultra violet radiation and lends
itself to application onto complex contours.
Weathered but watertight after 25 years
Excellent adhesion ensures no peel-back of the
edges making Belzona ideal for localised repair,
where corner leaks can be promptly eliminated. In
2008, one corner of a roof on a Military base in the
US was repaired in one day and the roof was leak
free the following morning when a storm came in.
European Technical Approval ETA-05/0075
states that the expected economically reasonable
working life of Belzona 3111 (Flexible Membrane)
roofing system is 25 years. The certificate was
issued by the British Board of Agrement and is
available to view online through their database.
Difficult contours, where other repair attempts
have failed are not a problem for Belzona. In 2007
NOSA hangar’ skylights were leaking and several
earlier attempts to seal them proved futile. Utilising
cold applied Belzona 3111 (Flexible Membrane)
system all 16 skylights were sealed and leaks
eliminated, not compromising on the appearance
of the roof.
Leaking skylight
Belzona 3111 (Flexible Membrane) is a proven
weatherproofing solution with known applications
in service for over 25 years. In Cilfynydd, South
Wales in 1988 a roof project was completed by
applying a Belzona high performance, liquid
applied membrane system to a flat roof. When
inspected 25 years later the membrane system
has remarkably withstood all climatic and
movement conditions and has provided full barrier
protection despite a quarter of a century of British
weather.
UK observatory revisited in 2010,
still in perfect condition
www.belzona.com
Completed Belzona application
01423 567641
Reader Enquiry: 18
13