DOORS&WINDOWS
The Triple Glazing Debate
As triple glazing continues to
grow in popularity, Neil Ginger,
CEO at Origin, discusses the
implications to the glazing
industry.
Over the last five years, Origin has
seen a steady rise in the demand for
triple glazing as building regulations
become more stringent and
homeowners become increasingly
conscious of the thermal efficiency
of their homes. But while the
thermal and acoustic benefits are
widely reported, triple glazed units
are not without issues.
The first issue, faced by
manufacturers, is production.
Origin has been offering the choice
of triple glazing in its bespoke
aluminium bi-fold doors for the
last three years, so understands the
main issues faced by manufacturers
of doors and windows.
Whether a window unit or a
bi-folding door, the product must
be designed to accommodate
triple glazing. This can be done
by changing the gasket or the
bead size. The manufacturer will
also have to review the tolerances
of each component to make sure
they are capable of bearing the
extra weight, which will involve
product testing. This may also
lead to product development
and alterations for stronger
components.
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AUG 2014
As a British manufacturer that
has complete control over the
design, manufacture and fabrication
of all its bi-folding doors and
windows, we are able to meet the
requirements of customers on
a bespoke product with a zero
lead time service. However, for
system companies that outsource
fabrication, this will not be as
simple. A larger amount of space
and stock, such as different beads
and gaskets, will be required to
produce the triple glazed units,
while operations and processes will
have to be seamless if errors are to
be avoided as the order moves along
each process.
For installers, consideration
must be given to the weight
implications of triple glazed units
as the extra glass will mean the
sets will be significantly heavier.
This will mean fewer units can be
delivered at any one time due to
the maximum weight loads for
vans or lorries. This can also affect
the number of journeys an installer
must make to site with the units.
A glass lifter may also be required
if large expanses of glass have been
specified, which may again increase
the cost of installation.
Bi-folding doors create a view
of the garden and let in the
maximum amount of natural
daylight. However, due to the
additional weight of triple glazing,
the maximum panel size available
for a bi-folding door is smaller than
a double glazed alternative. This is
because larger triple glazed doors
would be too heavy to operate
and would not be fit for the end
user. By reducing the maximum
panel size, an additional door is
also required, which increases the
amount of aluminium door frame
interrupting the view.
In some cases, the efficiency of
high performance double glazed
doors is almost as good as, if not
better than, that of a triple glazed
unit. Origin’s double glazed bifolding doors can achieve 1.67 W/
(m2K) using 24mm units which
is superior to some manufacturers’
triple glazed products. In essence
installers need to ensure consumers
understand that the U Value can
vary greatly across folding sliding
doors and that simply asking for
triple glazing isn’t always going to
be the answer, the manufacturer
matters too. For instance Origin’s
aluminium triple-glazed bi-folding
doors have a certified U Value
of 1.3W/(m2K), surpassing the
British Building Regulations by an
industry leading 27 per cent.
Triple glazed bi-folding doors
and windows can cost up to
double the amount of a double
glazed alternative. As it will be the
homeowners who benefit from the
energy savings made from triple
glazing, it will have to be assessed
whether the value added to the
property will outweigh the high
initial cost of triple glazed units.
Despite the issues currently in
debate regarding triple glazing,
each project is different and it is
clear that triple glazed units can be
beneficial to the thermal efficiency
of homes. The versatility and
strength of aluminium bi-folds
means complex layouts, such as
moving corner posts and bay set
ups, can incorporate triple glazing
without being too heavy.
By weighing up the pros and cons
of triple glazing, it is clear that more
consideration must be given to the
issues if people are to be offered
triple glazing as a viable alternative
to double glazing.
To read more, visit www.clearview-uk.com