Technical Paper 9 Slim-profile double glazing - Historic Scotland

Executive
Summary
The
embodied
 energy
has
been
 calculated
for
a
number
of
retrofit
 window
and
glazing
unit
options
 for
 use
 in
 traditional
 buildings,
 specifically
 category
 ‘B’
 listed
 Georgian
 tenement
buildings
 in
 the
 UNESCO
 World
 Heritage
 Site,
 Edinburgh,
 as
 part
 of
 Changeworks’
 Double
Glazing
 In
 Listed
 Buildings
 project.
 This
 Cradle‐to‐Site
 analysis
 incorporates
 data
 relating
 to
raw
material
extraction
and
processing,
manufacturing
and
transportation.
This
 report
 finds
 that
 Krypton
 gas
 filled
 units
 demonstrate
 lower
 embodied
 energy
 values
than
units
with
a
mix
of
heavier
gases.
The
omission
of
inert
gases
in
Pilkington
Energikare
units
 significantly
 reduces
 their
 embodied
 energy,
 but
 further
 research
 is
 required
 to
establish
the
manufacturing
energy
of
vacuum
unit
designs.
It
also
finds
that
transportation
energy
 can
 be
 significant
 in
 Cradle
 to
 Site
 analyses
 and
 demostrates
 the
 increased
environmental
impact
of
air
freight
over
more
sustainable
means
of
transport.
It
 is
 recommended
 that
 these
 embodied
 energy
 figures
 be
 used
 in
 combination
 with
operational
 energy
 consumption
 analysis,
 based
 on
 the
 individual
 U‐values
 achieved
 by
various
 unit
options.
 This
type
of
analysis
is
likely
to
expose
 greater
differences
in
options
when
evaluated
over
a
40‐year
operational
lifecycle.
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