Design For Deconstruction - US Environmental Protection Agency

SETTING PRIORITIES DESIGN FOR DISASSEMBLY
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Wood is quite low in embodied carbon emissions
since nature manufacturers the wood and manufacturers
just harvest and mill it. On much of the west coast,
framing lumber is not kiln-dried, which increases wood’s
embodied carbon. Wood in fact sequesters significant
amounts of carbon, as long as the wood does not decompose
or burn. And the planting of forests and sequestration
of carbon is one of the important strategies for addressing
climate change. On the other hand, the choice of carbon
as a metric in this case does not reflect wood’s potential
ecological impacts due to poor forestry practices.
Salvaged wood requires very little additional energy to
process, so new emissions are limited primarily to transportation.
The key to retaining woods value through cycles of
reuse is to maintain it for the highest and best use. The
value of wood products vary by at least a factor of ten
based on the size, cut, and character of the wood. Larger
pieces retain more of their value as they offer the most flexibility
for reuse or remilling and are easier to salvage than a
large number of small pieces. Notching or drilling framing
lumber for utilities creates defects in the wood that reduce
its value and potential for reuse. These and other strategies
from maintaining the value of wood are explored in the
Chartwell School Case Study that follows.