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The first part of
understanding how “green” applies to
handcrafted log building comes
through a description of the
building process starting with
acquiring raw materials.
Trees themselves
store/sequester carbon throughout
their lifespan and release it after
they die and decay in the forest.
Logs needed for handcrafted
log structures come from mature
trees near the end of their lifespan
so when trees are selectively
harvested for that purpose the
carbon they contain remains in the
tree and stays there for as long as
the building is standing.
It’s early for a track record
in North America, but longevity of
log structures in northern Europe
and Scandinavia is measured in
centuries.
Of the remaining parts not
used in construction, limbs and
cones remain in the forest providing
nutrients and seeds, and bark
removed at the log building yard
finds use as landscaping material or
is composted.
Significantly, little energy
is expended in the form of fuel and
petroleum products in the process of
taking a tree from the forest and
making it ready as a log for
building purposes.
Human effort is required to
remove bark and preserve the unique
characteristics of each log.
All things considered, the
end result of using mature trees for
handcrafted log construction is a
net removal of carbon from the
environment.
When building
handcrafted log homes, logs needed
for the dwelling are harvested and
transported straight from the forest
to the building site for peeling and
constructing.
Logs are air dried naturally.
After the logs are placed on
the log wall, all that there is left
to do before you have the finished
product is the pressure washing,
sanding and staining of logs.
When building stick
frame and timber frame homes, there
is extra transportation involved,
from the forest to the sawmill, from
the sawmill to the lumber yard, and
from the lumber yard to the building
site.
After milling the logs into
lumber, you end up with much more
waste wood like slabs and sawdust.
The drying of the lumber by
the kiln takes more energy and heat.
The end result of that
process is either carbon neutral or
a net addition of carbon into the
environment.
It’s worth noting that sawing
logs for timbers (four slab cuts) is
right next to processing logs for
use in handcrafted construction and
also results in net removal of
carbon from the environment.
Trees used for both
handcrafted log home construction
and timber frame construction
represent a very small percentage of
timber cut each year.
Still, it’s worth pointing
out that both craft industries are
doing their part to control carbon
emissions.
When not building
with logs, extra building materials
are necessary.
These extra building
materials include insulation,
sheetrock and exterior siding, which
are not environmentally friendly.
After sanding and staining
the logs in a handcrafted log home,
the building process is complete.
Throughout the
whole building process of a log
home, from peeling of the logs to
the end product on the log wall, the
only gasoline being consumed is that
which is necessary to run the
chainsaw and the crane.
Current methods of determining
r-values for log walls under-report
the effective r-value.
Log home utility bills for
heating and cooling suggest much
better thermal performance than
current methods for calculating
r-values describe.
Specific research on the
thermal performance of log walls is
needed to provide more precise
information.
Given the long list of
factors that determine log wall
thermal performance in a particular
climate zone, the resulting
information could be expressed as an
r-value equivalent to be of value to
the building industry."
Anecdotal evidence
obtained through utility heating
bills demonstrates this unique
quality, but more formal laboratory
testing needs to be done for more
precise information.
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