Other Styles Emerge
When you read or hear about a “historic” cabin the picture often comes
to mind of a cracker box rectangle structure with a low pitched roof.
In reality, log cabins today can be every bit as complex – and
considering the work which goes into them to create the joinery and
aesthetics they’re even more complicated – than even the most exotic
stone or stick structure. By the mid-1800s a new style of cabin
was emerging out of the wooded mountains of the northeast.
Referred to as “camps”, getaway spots for the wealthy sprouted up
around lakes and rivers using locally-grown timber. Using native
trees to provide whole or split logs for framing was a financial
consideration – it was much cheaper than hauling milled lumber into
the remote, often difficult to reach locations. The camps often
relied on larger than normal fireplaces made of native stone to ward
off the frigid northeastern chill.
A warm and welcoming modern log home.
By the late 1800s the “Adirondack” cabin style was gaining popularity.
The rustic beauty and simplicity of materials combined with the
architecturally appealing angles made it a popular choice when the
federal government established the first national park, known then as
a public reservation, at what is now Yellowstone National Park.
It would take another 44 years before President Woodrow Wilson would
sign into being the National Park Service in 1916. But by then
several log and stone buildings had been erected in Yellowstone,
Old Faithful Inn built in 1903-1904, and still touted as
the largest log structure in the world. The building was built
from lodgepole pine and rhyolite stone, both native to the region.
In the more than 100 years since being completed, the log structure
has played host to millions of tourists.
Old Faithful Inn, Yellowstone National Park
By the early 1930s the economy in North America was faltering.
The stock market crashed, the Great Depression began, and thousands
upon thousands of jobs dried up. As a way of jumpstarting the
economy, President Franklin D. Roosevelt created a plan to put
men back to work building public buildings and infrastructure.
He created the Civilian Conservation Corps, or CCC, in 1933 and for
the next nine years thousands of workers built log lodges and other
public-use buildings throughout the west for the National Park Service
and Forest Service.
By the latter part of that decade the government formed yet another
back-to-work program titled the Works Progress Administration, later
changed to the Work Progress Administration, or WPA. Once again,
unemployed workers were given paid jobs building schools, park
buildings and bridges across the nation. This time rustic log
influence was infused with board, batten, and stone construction in
park housing, administration and information buildings. The WPA
did projects in every state in the nation, with many buildings still
in use today.
Whether a log home or outbuilding for personal use, or a majestic
hotel or visitors center for a national park, most log buildings share
one of two roof structures – purlin or rafter. A purlin roof
uses additional courses of horizontal logs to tie into the gable logs.
Older log homes often used low pitched roofs with only two or three
purlin logs in addition to the main beam. But in areas of heavy
snowfall, and as square footage of living space became more important,
the pitches of roofs increased to allow a true second floor living
space. Now a half dozen or more purlin logs to create a high
gabled roofline is common.
Large beams can be used to tie walls together and
serve as roof support purlins and rafters.
As with any construction method, a high-pitched roof handles heavy
snowfall better. Also, a higher pitch to the roof can be
beneficial in warding off leaks depending on the roofing material
used. The purlins support the rafter logs, which in turn
traditionally supported smaller roofing purlin strips onto which
hand-split shingles were nailed. Later on roof sheeting and
composite shingles came into being and replaced the roofing purlins
holding the individual runs of wooden shingles. But composite
shingles just don’t carry the same warmth as wooden shingles, or even
With a true rafter roof, sawmill cut boards were used to build rafters
supported by a main beam. The rafters were placed closer
together to eliminate the need for larger supportive purlin logs.
If anything, supports made of sawn boards were used in place of log
purlins. Roofing purlins would then be nailed horizontally in
courses onto the rafters to accept shingles made of pine or cedar.
As alluded to in the previous paragraph, roofing purlins are used
today to support runs of corrugated metal.
If the cabin or home has an open, or cathedral, ceiling and will be
heated it’ll be necessary to insulate the underneath face of the
metal. Otherwise the temperature difference between the cold
outer and heated inner surfaces will cause the metal to develop
condensation and “sweat” in the winter. No one wants to sit
inside a warm cabin and be rained on from a sweating roof.
walls and a metal roof make for a timeless look. Metal
roofing has been used on log homes since it was first invented.
A metal roof is still an ideal practical and aesthetic choice.
As with every other aspect of log construction, the process of
insulating between the logs has undergone major improvements in the
past couple thousand years. History shows the first substance to
be used for sealing openings between logs was mud. Eventually
someone thought to mix dried moss with the mud to provide additional
insulating qualities and help hold the mud together.
As time marched on, the filler between the logs was given the name
“chinking”. The use of mud eventually progressed to more of a
mortar mix. Then in the latter 20th century, with the
discovery and improvement of plastics, the preference turned to
materials that stay somewhat elastic despite heat or cold.
Several companies now offer products with names like “Perma-Chink”
which offer a better seal, less prone to drying and cracking.
With the development of D-style logs, the need for chinking was
reduced drastically. Instead of courses of logs being dovetailed
or otherwise notched and joined, which leaves large gaps between each
course, now walls could be stack in an almost solid horizontal stack.
Every other course extends past the corner locking the logs together
with the walls attaching at both ends. The next layer of logs
falls just short of the corner while the same course of logs on the
two adjoining walls extends past the corner this time. Then the
process repeats itself until a solid structure is built. Joints
at the corners are sealed with a permanent chinking or silicone
sealant. As the logs complete the drying process and settling it
will be necessary to seal the joints every few years.
Where D-style logs meet at the corners each
alternating course will extend past the corner. The next course
will be cut flush. Walls can be built first with the ends
trimmed afterward for uniformity.
With logs now tightly stacked to form a wall, what are the insulating
properties of the logs? The generally acceptable “R” value, or ability
to ward off cold, is one unit per inch of log thickness. If logs were
square, then a 6-inch log would have an insulating value of R-6.
But logs are not usually cut square. So you have to estimate the
thickness somewhere between where the surfaces of the logs touch and
the rounded faces. If a D-style log was cut eight inches tall
and 10 inches thick at its thickest, then the R value might be 9 – the
difference between the 8-inch mating faces and 10-inch thickness at
its widest curvature. The beauty is that if you purchase sawn
logs from a mill or log home supply company the R value math has
likely been done for you.
Instead of dovetailing this inside corner, the
builder chose to use a quarter-round cut cedar log. His wife
added the cute bear touch for added effect.
Long gone are the days when building yourself a log cabin meant
heading out into the timber dragging a crosscut saw and broad ax … and
having a strong back. Nowadays anyone can enjoy the warmth and
feel of living in a log home, and the amount of labor you contribute
is up to you. Log home companies are plentiful on the Internet,
and a log house can hold all the creature comforts and conveniences
found in any other home. From wiring and plumbing ran inside
specially-cut logs, recessed ducts and lighting hidden with well
though out plans, to exterior sealers that let the natural beauty of
the wood shine through for decades with proper care, modern log homes
offer it all with a look that remains forever timeless.