16 OUTSIDE MAGAZINE
09/10.
Dispatches Big Idea
FROMLEFT:^ KILIAN^O’SULLIVAN/VIEWPICTURES/UNIVERSAL^ IMAGES^GROUP/GETTY;DAVIDSUNDBERG/ESTOIf only there was a sturdy and renewable
building material—one that could actually
help curb climate change while giving us more
calming and aesthetically pleasing spaces in
which to live, work, and play.
Such a miracle substance exists, of course.
It’s wood. As you are no doubt aware, trees
absorb carbon dioxide and release oxygen
back into the atmosphere during photosyn-
thesis. The carbon is sequestered in the tree
while it’s standing and remains locked inside
wood products after it’s harvested for lumber.
(Large amounts of CO 2 are released only when
wood decays or is burned.) America’s oldest
standing wooden home, the Fairbanks House,
built in Dedham, Massachusetts, in 1637, is
still holding onto 400-year-old carbon today.
That’s a major reason why environmentalists
fight so hard to preserve existing forests and
plant new ones—studies suggest that it’s the
most useful thing we can do to mitigate cli-
mate change.
Cutting down a tree for lumber, of course,
ends its carbon-inhaling days. And even
within well-managed woodlands, refores-
tation takes a significant amount of time,
especially when you’re waiting on the large
specimens that are traditionally used in con-
struction. Still, over the long term, forestsmanaged for timber sequester carbon nearly
as well as wilderness woodlands do. And in
the U.S., we’re currently adding more trees
to our working forests than we’re cutting
down—there’s as much forest today as there
was in 1910, according to the Forest Service.
We can add a lot more if we develop con-
struction methods that make use of smaller
trees, which can be propagated in a few de-
cades, rather than giant ones that can take
centuries to grow.
Enter mass timber, a term for a category of
innovative products made from smaller pieces
of wood—such as two-by-fours and two-by-
sixes—that are either glued together or cross-
laminated to create beams, structural walls,
ceilings, and floors. These pieces can be pre-
fabricated to make building highly efficient.
And with the latest milling machinery com-
ing to market, even small-diameter trees like
black spruce can be used.
The Nature Conservancy is so bullish on
mass timber’s potential to drive reforestation
that it commissioned an exhaustive study,
involving 16 institutions across Europe and in
North and South America, investigating how
new practices might move the planet toward
the organization’s goal of expanding forests
by 500 million acres by 2030. “That wouldTrees are a
renewable building
material that
helps curb climate
change while giving
us healthier and
more aesthetically
pleasing spaces.There Will Be Wood
MASS TIMBER OFFERS A SMART
WAY FORWARD FOR LOGGING AND
CONSTRUCTION IN AMERICA, BUT
ONLY IF WE CAN LEARN HOW TO
GROW, HARVEST, AND PROCESS
TREES LIKE OTHER CROPS
BY MARC PERUZZI
HERE’S SOMETHING you probably didn’t
know: the construction business accounts
for an estimated 23 percent of the world’s
carbon-dioxide emissions—5.7 billion tons,
according to the most recent estimates.
Much of this comes from the use of concrete
and steel, the two biggest contributors to
emissions in the building sector. As the BBC
has reported, if the concrete industry were a
country, it would be the third-largest emis-
sions producer, behind China and the United
States. And there’s no end in sight: the United
Nations Environment Program predicts that
humans will put up the equivalent of a new
Paris every week for the next 40 years. In the
U.S., an architectural publication predicted
that some 1.9 billion square feet of new struc-
tures will be built in the next three decades.