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Green By Nature
As an independent CSSB member, we proudly offer
shakes and shingles from all manufacturers that
are lightweight, attractive, naturally decay
resistant, fire, wind and impact resistant, and
offered in a variety of product styles and
finishes. It is already a proven fact that
wood designed buildings consume less energy,
emit less greenhouse gases, release less air
pollution, discharge less water pollution, use
less resources from a weighted resource
perspective and produce less solid wastes than
steel or concrete designed buildings
(Pages 12-13, Energy and the
Environment in Residential Construction,
Sustainable Building Series, No.1, Canadian Wood
Council, 10M-09-04).
Cedar roofing materials have high R-values
(Thermal resistance) and this excellent
insulative quality keeps homes warmer in the
winter and cooler in the summer. This
conserves energy and reduces the imprint left on
the environment. The cedar shake and
shingle industry maximizes the wood resource
brought into its manufacturing facilities.
A little known fact about cedar shakes and
shingles is that many are actually made from
salvaged wood fibre, that is, wood left over
from past logging work or windblown material
left on the forest floor. With this
material being of unsuitable size for lumber
mills, cedar shake and shingle producers use
helicopter and manual methods to remove it from
the forests in a habitat sensitive way, thus
ensuring the best use of a valuable resource.
"Only one third of one percent of BC's forests
are logged each year. BC's land base is 95
million hectares (235 million acres), larger
than France and Germany combined.
Two-thirds of BC's land base is forested (60
million hectares or 149 million acres), an area
twice as big as all of the New England states
and New York state combined. More than
half of BC's forests (35 million hectares or 86
million acres) will likely never be logged."
(Source:
www.bcforestinformation.com/undisturbed_overview.asp).
Trees are a
renewable resource so the use of wood building
products is an environmentally sound choice.
Environmental Considerations
Cedar shakes and
shingles minimize the overall
environmental cost to society, thus
reflecting smart building practices.
As a specifier you need to make the
right building product choices for
your clients. Specifiers are
encouraged to check if the
particular green building system
used gives all types of building
products equal consideration. Some
helpful questions to ask are:
- Is the
building product manufactured
from a renewable resource?
- Is the
building product recyclable or
does it sit in landfills for a
long time?
- What is the
energy efficiency of the
building product once it has
been installed?
- How long has
the product been proven in
actual field applications?
- Are you
comparing LCA date calculated
with the same methodology and
date types?
With such an array
of data in the marketplace today,
informed, well-researched choices
will help clients the most.
Choosing wood, specifically cedar
roofing materials, is a decision
based upon sound judgment, proven
product performance and impressive
environmental benefits.
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The Marketplace Has Gone Green
The environmental attributes of building products are
important considerations for project specifiers. Architects,
builders and their clients now include environmental cost factors in
their decision making process. Life cycle data is to obtaining
green building ratings now commonly seen in request for proposal
documents. In 2007, the Cedar Shake and Shingle Bureau ("CSSB")
commissioned a Life Cycle Assessment of four Western Red Cedar Shake and
Shingle Roofing Products: 24" x ¾" Heavy Handsplit and Resawn Shakes;
24" x ½" Medium Handsplit and Resawn Shakes; 24" x 5/8" Tapersawn
Shakes; and 18" Perfection Shingles. The preliminary findings of this
report are included below.
Being certified or granted points under a
green building program requires the structure to meet a host of
detailed project criteria. Some of this project data can be
sourced through Life Cycle Assessment ("LCA") and especially its most
developed component, Life Cycle Impact ("LCI"). There are tools
that provide quantitative and scientific analyses of the environmental
impact of product and systems. These rating systems require
compilation/evaluation of material and energy resources used and
emissions to air, water and land throughout the life cycle of a product.
This included raw material extraction, through production and ultimately
to the product's end-of-life.
Life Cycle Impact Result
This table presents results for one of the
four products by unit on an absolute and percent
contribution basis per roofing square: Western Red Cedar
(WRC) 24" x ¾" Heavy Handsplit and Resawn Shakes
|
Impact Category |
Unit |
Total
WRC 24" x ¾"
HHRS |
Harvesting |
Resource
Transportation |
Product
Manufacturing |
| Global Warming |
kg CO2 eq. |
7.956 |
5.777 |
1.167 |
1.103 |
| Acidification |
kg H+ moles eq. |
6.106 |
4.936 |
0.613 |
0.560 |
| Eutrophication |
kg N eq. |
0.0055 |
0.0048 |
0.0005 |
0.0001 |
| Solid Wastes |
kg |
0.225 |
0.030 |
0.006 |
0,189 |
| Primary Energy |
MJ |
114,101 |
80.514 |
16.127 |
17.460 |
|
Impact Category % Contribution |
|
Total |
Harvesting |
Resource
Transportation |
Product
Manufacturing |
| Global Warming |
|
100% |
73% |
15% |
13% |
| Acidification |
|
100% |
81% |
10% |
9% |
| Eutrophication |
|
100% |
88% |
10% |
3% |
| Solid Wastes |
|
100% |
13% |
3% |
84% |
| Primary Energy |
|
100% |
71% |
14% |
15% |
Courtesy Athena Sustainable Materials
Institute, A Life Cycle Assessment of Western Red Cedar
Shake and Shingle Roofing Products, March 2007
To put some of the Table's results in
context, it was determined that the primary energy use and
global warming potential (greenhouse gas emissions) for a
square (100 sg.ft.) of heavy handsplit and resawn shakes was
equivalent to the energy released, and greenhouse gases
emitted from, utilizing a third of a 20 lb. BBQ tank of
propane. These results are considered to be quite low
when contrasted with similar results for alternative
building products and reflects the labor, rather than
energy, intensive nature of the manufacturing of handsplit
shakes. Production of WRC shakes and shingles has a
small impact on the environment, resulting in a high quality
product with a lower embodied effect. Co-products
produced during the manufacture of shakes and shingles
include wood chips, hog fuel and sawdust, all of which are
used later on as raw wood furnished for other wood products
manufacture, CO2 neutral biomass energy production and
landscaping mulch. A 2007 study conducted by the
Athena Sustainable Materials Institute determined that "less
than 1% of the incoming resource is categorized as waste
destined for landfilling."
(Executive Summary, A Life Cycle Assessment of
Western Red Cedar Shake and Shingle Roofing Products,
Athena Sustainable Materials Institute, March 2007)
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