Page 36 - Kutnar, Andreja, et al., eds., 2015. Proceedings of the 1st COST Action FP1307 International Conference - Life Cycle Assessment, EPDs, and modified wood. University of Primorska Press, Koper.
P. 36
e
cycle
impacts
of
modified
wood
products
Lauri
Linkosalmi1,
Kristiina
Laine2,
Lauri
Rautkari3
1
Aalto
University,
School
of
Chemical
Technology,
Department
of
Forest
Products
Technology,
Vuorimiehentie
1,
FI-‐02150
Espoo,
Finland,
lauri.linkosalmi@aalto.fi
2
KTH
-‐
Royal
Institute
of
Technology,
Department
of
Civil
and
Architectural
Engineering,
Division
of
Building
Materials,
Brinellvägen
23,
100
44
Stockholm,
Sweden,
kristiina.laine@byv.kth.se
3
Aalto
University,
School
of
Chemical
Technology,
Department
of
Forest
Products
Technology,
Vuorimiehentie
1,
FI-‐02150
Espoo,
Finland,
lauri.rautkari@aalto.fi
Keywords:
heat
treatment,
life
cycle
assessment,
sawn
timber,
thermal
modification
Wood
is
widely
utilised
in
the
built
environment
as
structural
and
non-‐structural
elements.
Wood
has
excellent
properties
as
a
building
material,
however,
some
wood
properties
(dimensional
stability,
strength,
and
biological
durability)
are
influenced
by
the
surrounding
moisture
conditions,
which
may
reduce
the
service
life
and
increase
the
need
for
maintenance.
In
order
to
control
the
interaction
of
wood
and
moisture,
different
wood
modification
methods
have
been
developed,
thermal
modification
(also
termed
heat
treatment)
being
the
most
widely
spread
and
commercially
utilised
process.
Life
cycle
assessment
is
a
coherent
tool
to
identify
environmental
impacts
through
the
whole
life
cycle
of
different
products
and
can
be
observed
in
three
aspects:
economic,
environmental,
and
social.
From
the
economic
view
point
thermally
modified
wood
may
be
more
expensive
compared
to
non-‐modified
timber
due
to
increased
processing
and
improved
performance
suited
for
a
certain
purpose.
Environmental
impacts
may
be
greater
in
the
manufacturing
phase,
however,
the
life
cycle
is
expected
to
become
longer
and
the
need
for
maintenance
is
reduced
due
to
the
improved
durability.
The
utilisation
and/or
production
of
toxic
or
harmful
chemical
compounds
in
the
modification
process
should
be
avoided,
which
is
not
a
problem
with
thermally
modified
wood
as
only
heat
and
water
vapour
are
added.
However,
some
extractives
are
released
during
the
modification
process
and
may
cause
an
increase
of
some
environmental
indicators.
The
recyclability
of
thermally
modified
wood
should
also
be
considered
as
one
of
the
main
factors
and
it
is
expected
to
be
similar
to
non-‐modified
timber,
but
the
main
difficulty
in
the
recyclability
of
wood-‐based
products
are
surface
treatments,
which
include
resins
and
metal
fasteners
that
are
often
used
in
building.
In
order
to
make
a
meaningful
analysis,
the
system
boundary
for
modified
wood
products
should
always
be
the
entire
life
cycle.
24
cycle
impacts
of
modified
wood
products
Lauri
Linkosalmi1,
Kristiina
Laine2,
Lauri
Rautkari3
1
Aalto
University,
School
of
Chemical
Technology,
Department
of
Forest
Products
Technology,
Vuorimiehentie
1,
FI-‐02150
Espoo,
Finland,
lauri.linkosalmi@aalto.fi
2
KTH
-‐
Royal
Institute
of
Technology,
Department
of
Civil
and
Architectural
Engineering,
Division
of
Building
Materials,
Brinellvägen
23,
100
44
Stockholm,
Sweden,
kristiina.laine@byv.kth.se
3
Aalto
University,
School
of
Chemical
Technology,
Department
of
Forest
Products
Technology,
Vuorimiehentie
1,
FI-‐02150
Espoo,
Finland,
lauri.rautkari@aalto.fi
Keywords:
heat
treatment,
life
cycle
assessment,
sawn
timber,
thermal
modification
Wood
is
widely
utilised
in
the
built
environment
as
structural
and
non-‐structural
elements.
Wood
has
excellent
properties
as
a
building
material,
however,
some
wood
properties
(dimensional
stability,
strength,
and
biological
durability)
are
influenced
by
the
surrounding
moisture
conditions,
which
may
reduce
the
service
life
and
increase
the
need
for
maintenance.
In
order
to
control
the
interaction
of
wood
and
moisture,
different
wood
modification
methods
have
been
developed,
thermal
modification
(also
termed
heat
treatment)
being
the
most
widely
spread
and
commercially
utilised
process.
Life
cycle
assessment
is
a
coherent
tool
to
identify
environmental
impacts
through
the
whole
life
cycle
of
different
products
and
can
be
observed
in
three
aspects:
economic,
environmental,
and
social.
From
the
economic
view
point
thermally
modified
wood
may
be
more
expensive
compared
to
non-‐modified
timber
due
to
increased
processing
and
improved
performance
suited
for
a
certain
purpose.
Environmental
impacts
may
be
greater
in
the
manufacturing
phase,
however,
the
life
cycle
is
expected
to
become
longer
and
the
need
for
maintenance
is
reduced
due
to
the
improved
durability.
The
utilisation
and/or
production
of
toxic
or
harmful
chemical
compounds
in
the
modification
process
should
be
avoided,
which
is
not
a
problem
with
thermally
modified
wood
as
only
heat
and
water
vapour
are
added.
However,
some
extractives
are
released
during
the
modification
process
and
may
cause
an
increase
of
some
environmental
indicators.
The
recyclability
of
thermally
modified
wood
should
also
be
considered
as
one
of
the
main
factors
and
it
is
expected
to
be
similar
to
non-‐modified
timber,
but
the
main
difficulty
in
the
recyclability
of
wood-‐based
products
are
surface
treatments,
which
include
resins
and
metal
fasteners
that
are
often
used
in
building.
In
order
to
make
a
meaningful
analysis,
the
system
boundary
for
modified
wood
products
should
always
be
the
entire
life
cycle.
24
