What Makes This Material Green?

The Green Roundtable
and

What Makes This
Material “Green”?

(copyright © Green Roundtable 2007)

Green Roundtable

Consulting, education, training
and strategic planning

to create healthy environments by
integrating principles of
sustainability into mainstream
planning, design and construction.


Objectives
Answer the following questions:

- What is the imperative for ‘doing green’

- What makes a material green

- What are some of the tools we can use to pick green
materials

- What other factors must be considered besides
‘greenness’

- Where are the suppliers


Why do green….

4

Some sad realities….
Even if you don’t believe that the global warming
threat is real, we are facing these certain realities:
• Ozone depletion
• Air & water pollution
• Destruction of worlds forests & green spaces
• Species & biodiversity loss
• Acid rain
• Collapse of world’s fisheries
• Fresh water scarcity
• Topsoil loss; Soil contamination
5

And if global warming is real…

• Crop failure on a massive scale
• Increases in drought frequency
• Deadly heat waves
• Rising sea levels/ coastal flooding
• Increased frequency & duration of storm activity
• Expansion of desert areas
• Increases in disease vectors

6

On a more local or personal level…

• Rapidly rising energy costs
• Escalating prices on consumer goods
• Blackouts/ brownouts
• Water shortages
• Supply chain interruptions
• More frequent economic losses due to increased
storm intensity & flooding

7

Some sobering facts…

The United States produces 25% of global
greenhouse gas emissions. Americans
produce twice as much per person than other
industrialized nations

8


Water tables are now falling in countries that
contain over half the world’s people

9


There are currently 1,243 EPA Superfund
sites on the National Priorities List and 60
more proposed (as of 3/20/07)



The incidence of asthma has increased
dramatically over the last 25 years in the U.S.
and other industrialized nations.

11


The EPA estimates that indoor air can be up
to five times as contaminated with VOCs as
outside air.

12


The EPA also reports that the airborne
contaminants found in our homes are three
times more likely to cause cancer than the
pollutants outside



Cancer clusters have been identified in
some more-affluent communities and have
been attributed to chemically-intensive
landscape management practices

14


A 15-year study in Oregon concluded that
women who work in the home have a 54%
higher death rate from cancer than women
who work outside the home



China recently caught up to the United States
in terms of overall energy consumption.

India isn’t far behind.

The U.S. & Canada are still the per capita
leaders by far

16


The U.S., with 5% of the worlds population,
consumes more than a third of it’s resources
and over a quarter of its energy resources.

17

Food for thought….

18

19

Perhaps the most sobering fact of all…

It has been estimated that in order for the current
population of the Earth to live at the same quality of life as
the industrialized nations, it would require the resources of
four ‘Earth equivalents’.

20

This we know…

We live on a planet of finite natural resources

We are currently using those resources at an
unsustainable rate

As a nation, the United States uses a disproportionate
share of the world’s natural resources

These conclusions are rooted in simple physics,
chemistry, biology and economics

21

A solution:
Green Building

22

Defining green building:

The effective and responsible integration
of the built environment into the natural
world to protect natural resources and
ensure healthy and comfortable indoor
environments

23

Why build green?
Building green:
• Reduces the ecological footprint of the building
• Creates a safer and healthier indoor environment
• Saves on utility expenses
• May improve property resale value
• May increase affordability
• Typically results in a more durable, maintenance-
free building
• Provides security/ passive survivability
• Reduces our dependence on foreign oil

What makes it green?

• Low embodied energy (entire lifecycle)

• Minimizes impact on wildlife habitat, green space,
waterways, etc

• Minimizes depletion of natural resources

• Poses minimal harm to humans during its
manufacture, transport, installation, end-use or
disposal


Underlying all:

Scale
Scale
Scale


Consider this:

The average size of a U.S. single-family
house has increased by 33% since 1975. At
the same time average family size has
decreased.


How green is it?

• The “no-build” option is always the greenest way

• Smaller is greener

• More efficient material resources use is better

• The more durable (in use) & maintenance free the
better

• The lower the operating energy, the better


The LEED Credit Categories

Sustainable Sites

Water Efficiency

Energy & Atmosphere

Materials & Resources

Indoor Environmental Quality

Innovation & Design Process


Life-cycle analysis & embodied energy

• Life-cycle analysis is an examination of all of the
energy & resources that go into a product and their
associated impacts- environmental, economic,
health, etc.

• Embodied energy typically occupies central position
in any LCA

• For LCA to be effective, you need to try to identify all
of the ‘upstream’ energy & resource inputs

• This is often easier said than done!


Life-cycle stages to consider

• Extraction & harvesting
• Manufacture/ production
• Storage/ Warehousing
• Transportation
• Assembly & Installation

• End use (including maintenance)
• Disassembly/ demolition
• Transportation of waste
• Waste processing/ disposal


What is embodied energy?

The quantity of energy required to manufacture, and
supply to the point of use including:

• Extraction • Assembly
• Transportation • Installation
• Manufacturing • Some definitions also include:
Disassembly & Removal


And don’t forget about embodied water!

• The food we consume each day requires
2,000 quarts of water to produce

• Two and a half billion gallons of water were
used to replace the aluminum cans trashed in
2001 with new cans made from virgin
materials.
(http://www.bottlebill.org/about_bb/benefits/wa
ste-alum.htm)


A new paradigm:

The Cradle-to-Cradle Lifecycle
See McDonough Braungart Design Chemistry
http://www.mbdc.com/c2c_home.htm


Cradle to Grave: Linear flow

Materials
extraction/ Mfg/
harvesting Processing End Use Disposal


Cradle to Cradle: Cyclical

End Use

Demolition/
Re-Manufacture/
Removal/
Re-Processing
Collection


Choosing green materials

38

General methodology:
• Define what makes a product green

• Identify ‘best in class’ product characteristics

• Don’t forget to factor in performance & durability
characteristics

• Verify green claims using 3rd party resources

• Identify your most important selection criteria

• Compare products side-by-side

• Get additional guidance from suppliers
39

Points to remember
• It may be difficult to determine the best-in-class
for a product category

• Determining most important criteria can be very
subjective

• Certain greenness criteria may be more important/
applicable to some product classes than to others

• A product may be green on some attributes but not
on others

• Need to be wary of so-called “green” resources
sponsored by manufacturer associations
40

Selection criteria: Materials
• Efficiently uses energy & resources
• Derived from rapidly renewable resources
• Contains re-used/ salvaged material
• Contains high recycled material content
• Can be reused/ recycled at the end of it’s useful life
• Can be down-cycled at the end of it’s useful life
• Biodegradable
• Locally sourced
• Poses minimal harm in production, use, disposal
• Economics & environmental justice also important!

Recycled Content

Post-Consumer vs. Pre-Consumer
aka Post-Industrial


The Precautionary Principle

Precautionary Principle: "When an activity raises
threats of harm to human health or the
environment, precautionary measures should be
taken even if some cause and effect relationships
are not fully established scientifically. In this
context the proponent of an activity, rather than
the public, should bear the burden of proof." -
Wingspread Statement on the Precautionary
Principle, Jan. 1998
(http://www.sehn.org/wing.html)

43

Some things we may want to write off:
• Vinyl-based products

• Products containing heavy metals like arsenic

• Products containing halogenated fire-retardants

• Products that emit excessive amounts of
formaldehyde

• Appliances that contain HCFC’s and do not meet the
standards referenced by LEED


3rd Party Resources for Judging Products

• Online green product databases (e.g. GreenSpec)

• Certification organizations (GreenSeal, FSC, etc.)

• LCA software tools (BEES, PHAROS, etc.)

• Manufacturer Material Safety Data Sheets

• Other online databases like NIH hazardous materials
database


Online resources

• Environmental Building News/ Greenspec-
http://www.buildinggreen.com)

•http://www.austinenergy.com/Energy%20Efficiency/Progr
ams/Green%20Building/Sourcebook/index.htm


Product Certification

• GreenSeal (www.greenseal.org)

• Scientific Certification Systems
(www.scscertified.com)

• GreenGuard (www.greenguard.org)

• Green Label (http://www.carpet-rug.org/) (2nd party)

• Forest Stewardship Council (http://www.fscus.org/)


Green Seal Product Categories
• Alternative Fueled Vehicles (GC-02)
• Anti-Corrosive Paints (GC-03)**
• Cleaning Services (GS-42)
• Coated Printing Paper (GS-10)
• Commercial Adhesives (GS-36)
• Compact Fluorescent Lamps (GS-05)+
• Degreasers (GS-34)
• Electric Chillers (GS-31)
• Fleet Vehicle Maintenance (GC-10)
• Food Service Packaging (GS-35)

• Green Procurement Criteria (GS-38)***
• Green Facilities Operation and Maintenance Criteria
(GS-39)***
• Household Cleaners (GS-08)
• Industrial & Institutional Cleaners (GS-37)#
• Industrial & Institutional Floor-Care Products (GS-40)
• Industrial & Institutional Hand Cleaners (GS-41)
• Lodging Properties (GS-33)
• Newsprint (GS-15)
• Occupancy Sensors (GC-12)

• Paints (GS-11)**
• Paper Products Used in the Preparation of Food
(GC-08)
• Paper Towels and Paper Napkins (GS-09)
• Powdered Laundry Bleach (GC-11)
• Printing and Writing Paper (GS-07)
• Recycled Content Latex Paint Standard (GS-43)
• Re-Refined Engine Oil (GS-03)
• Reusable Utility Bags (GS- 16)



• Tissue Paper (GS-01)
• Windows (GS-13)
• Window Films (GS-14)


Software tools

53

A sampling of software tools

• BEES 4.0 (see next slide)
• Pharos (http://www.healthybuilding.net;
http://www.pharosproject.net/)
• Sylvatica (http://www.sylvatica.com/tools.html)
• LISA (http://www.lisa.au.com)


http://www.bfrl.nist.gov/oae/software/bees.html


PHAROS


Other tools/ methods

• Check “SIRI” database for Material Safety Data
Sheet (MSDS) at http://siri.uvm.edu/index.html

• Check for known dangers/ toxicity at NIH
Household Products Database
(http://householdproducts.nlm.nih.gov/index.htm)

• Check NIH Toxnet Database
(http://toxnet.nlm.nih.gov/)

• Contact manufacturer


Considerations for
Choosing Best-in-Class
(a brief sampling)


What makes it green? (in review)
The jumping off point for all product classes:

• Low embodied energy (entire lifecycle)

• Minimizes impact on wildlife habitat, green space,
waterways, etc

• Minimizes depletion of natural resources (rapidly
renewable, recyclable, etc.)

• Poses minimal harm to humans during its
manufacture, transport, installation, end-use or
disposal


Lumber

• From sustainably managed forests

• Sourced locally

• Naturally decay-resistant

• Easy to work with (milling, finishing, etc.)

• Locally salvaged or salvaged from demo phase

• Sawdust & natural volatiles non-toxic


Engineered lumber/ composites
(sheet goods, plywood)
• Contain recycled fibers or rapidly renewable fibers
(FSC, GreanSeal, SCS, etc.)

• Made w/ low-VOC, formaldehyde-free adhesives

• Dimensionally stable, warp resistant

• Accepts finish well

• Good screw-holding characteristics

• Moisture & mold resistant


Paints

• Low or no VOC; low odor

• Pose minimal occupational hazard during
manufacture (meets ISO 14001, OSHA, etc)

• Good coverage (minimal coats)

• Durable- scrubbable

• Easy touch-up (e.g. good color matching w/ old vs.
new)

• Do not pose a disposal hazard


Adhesives/ Sealants
• Low or no VOC

• UV resistant

• Flexible (or not, depending upon application!)

• Freeze-tolerant

• Easy clean-up

• Adequate ‘open time’

• Do not pose a disposal hazard


Carpeting and Flooring
• Formaldehyde-free

• Made from rapidly renewable or recycled materials

• Durable- abrasion, impact & moisture resistant (hard
flooring)
• Stain resistant
• Mold resistant (carpeting)
• Simplified installation (e.g. doesn’t require adhesive)
• Requires minimal maintenance (cleaning,
refinishing)
• Easy sectional replacement (e.g. carpet tiles)

Exterior Decking

• Requires a minimum of maintenance (sealers, etc.)

• UV & fade resistant

• Stable- resistant to checking & warping

• Naturally decay resistant

• Recyclable (I.e. Trex vs. all-plastic)


Insulation
• Formaldehyde free (e.g. binders in fiberglass batts)

• High recycled content (fiberglass, cellulose, denim)

• HCFC-free blowing agents (foam board)

• High thermal insulating characteristics! Good
resistance to air infiltration (these may trump other
factors if it can reduce embodied energy of structure
enough)

• Moisture/ mold resistant

• Low flame-spread/ non-combustible


Kitchen counters

• Mechanically fastened

• Durable- Abrasion, heat & stain resistant

• Require minimal maintenance

• Easily resurfaced

• Minimal off-gassing from adhesives/ binders


Exterior Siding

• Weather resistant; UV resistant

• Easy to install

• Breathable

• Requires fewer paint/ refinishing/ repointing cycles


Roofing

• High-reflectance (improves longevity, minimizes heat
island effect, keeps building cooler in summer)

• Wind & UV resistant; fire-resistant; impact resistant

• Easy to repair

• Low or no maintenance requirements


The product selection matrix:
Detailed


Detailed Life-Cycle Impact Workheet- Interior Wall Paint

AFM SafeCoat Comments PPG Pure Performance Comments
Manufacturer AFM Enterprises Pittsburg Paints
Where manufactured San Diego, CA Dover, DE
Impact Criteria:
Raw mat'l Main constituents Manufacturing outsourced vinyl acetate ethylene
extraction resins

Where raw mat'ls aquired Not determined Not determined
Distance to mfgr plant (raw matls) Not determined Not determined
Renewable feedstocks Not determined Not determined
Recycled content Not determined Not determined
Mfg. phase Plants ISO 14001 certified Not determined Yes
OSHA-compliant plant Yes Yes
Toxics/carcinogens in mfg Yes But less than conventional Yes But less than conventional
EPA VOC Guidelines followed Yes Yes
Aromatic solvents used in mfg No No
Heavy metals used in mfg No No
Water-based? Yes Yes
% mfg waste reclaimed Not determined Not determined
How mfg waste disposed Not determined Not determined
Water conserv./recycling in mfg? Yes "No wastewater discharge"
Recycled packaging No No
Use phase Distance: mgfr to end-use ~3000 mi. < 500 mi.
Life-expectancy Mfg: "Typical life exp."
Durability "same as premium latex" Same as conventional
Maintenance req'd.?
Maint. procedure
Maint. environmental impacts
Zero VOCs in end-use? Yes Yes
VOC content, base product Zero Zero
Independently certified VOC free? No Yes
Tints/Colorants VOC-free? Yes If AFM colorants used No < 2g/liter, max.
Formaldehyde-free? Yes Yes
Meets SCAQMD Reqs. Yes Yes
Safe for chemically sensitive? Yes Not determined
Enviro. precautions req'd. Yes Yes Air quality, disposal
Nature of precautions Air quality, disposal "Use adeq. ventilation" Air quality, disposal
"Disposal" Product recyclable? No No
phase Ease of dismantling/recycling Low Low
Take-back program available No No
Recycling infrastructure in place No No
Re-useable? No No
Biodegradable? No No
RCRA Hazardous material? No See MSDS No See MSDS
Const. waste disposal General C&D waste "Let dry out" General C&D waste "use absorbant
Packaging recyclable No No
Packaging take-back No No
General Environmental policy/commitment Yes Yes
Green Seal certified No Yes Class "A" rating


The product selection matrix:
Condensed


General Environmental Impact and Selection Criteria
Wall Paint
AFM Pittsburgh
Safecoat Pure
Criteria:
GWP Moderate Moderate
Fossil Fuel Depletion Moderate Moderate
Transportation Energy Moderate Low
Indoor Air Quality Low Low
Disposal, left-overs Moderate Moderate
Disposal, end-of-life Moderate Moderate

Durability High High
ISO 14001 Cert. No Yes
Green Seal Cert. No Yes
Environmental Commitment
High High

General Environmental Impact and Selection Criteria
Wall Insulation
Owens-Corning National Fiber
Miraflex Cel-Pak
Criteria:
GWP Very High Low
Fossil Fuel Depletion Very High Low
Transportation Energy Moderate Low
Overall Embodied Energy Excessive! Low
IAQ Low Low*
Disposal, const. waste Low to Moderate Low
Disposal, end-of-life Low to Moderate Low

Rapidly Renewable No Yes
Certified Recycled Content NA Yes
Durability/ Longevity High High
Thermal Performance Moderate High**
ISO 14001 Cert. ND ND
Green Guard Cert. Yes No
Environmental Commitment High ND

* Odor may be problem for some
** Due to higher R-value and resistance to air infiltration

Green Practice:
General Considerations for
Choosing & Using Materials
(a sampling)


Lumber

• Use advanced framing to minimize lumber use; use
efficient planning to minimize waste (also use layout
software- Google layout & cut list software)
• Use FSC certified lumber (Forest Stewardship
Council; www.fsc.org)
• Use salvaged lumber from specialty suppliers like
Longleaf Lumber in Cambridge (617-871-6611)


Lumber, cont.
• Get FSC lumber from Sterritt Lumber in Watertown
(617-923-1480) or Mass Woodlands Cooperative
(413-397-8800; www.masswoodlands.coop)

• Suppliers with stated commitment to sustainable
forest management like Highland Hardwoods in
Brentwood, NH (www.highlandhardwoods.com)

• For a view of sustainable forestry practices, see
Hancock Land Co. in Maine (www.hancockland.com)
and Cowl’s Lumber in N. Amherst, MA
(http://www.sawmilltimbers.com/html/sustainable.html)

• Remember to use local sources whenever possible!

Lumber/ Lumber Finishing

• Use lumber salvaged from demolition phase

• Avoid use of tropical hardwoods

• Use natural finishes like salad bowl oil (unscented),
mineral oil, beeswax (waxes may contain petroleum
distillates)

• Use low-VOC clear finishes (e.g. water-soluble
polyurethane) from companies like AFM Safecoat


Engineered lumber/ composites
(sheet goods, plywood)
• Use solid lumber whenever possible (except for
structural use)
• Choose formaldehyde-free varieties
• Use exterior grades of plywood or MDF (medium-
density fiberboard); they contain phenol-formaldehyde
binders rather than formaldehyde-based resin binders,
which are generally safer; favor plywood over OSB
• Examples of formaldehyde-free MDF (fiberboard):
Medite or Medex from Sierra Pine (sierrapine.com)
or Extira (cmicompany.com)
• Look for SCS (and FSC) certification


Paints
• Use low or no VOC paints
• Make sure paints are Green Seal or Scientific
Certification Systems certified (www.greenseal.org;
www.scscertified.com)
• Brands:
- Sherwin-Williams Harmony
- Benjamin Moore Aura (& Ecospec)
- Pittsburg Pure Performance
- AFM Safecoat (www.afmsafecoat.com)
- The Old Fashioned Milk Paint Company
(www.milkpaint.com)
- Livos plant paints
(http://www.floorings.com/livos.html)
- Yolo Colorhouse (See bettencourtwood.com)

Adhesives/ Sealants
• Use low or no VOC varieties

• Look for Green Seal or Scientific Certification
Systems certified (www.greenseal.org;
www.scscertified.com)
• Water-soluble varieties generally safer


Carpeting and Flooring
• Choose formaldehyde-free varieties
• Look for Carpet and Rug Institute Green Label
designation for carpets (http://www.carpet-rug.org/)
• Choose natural fiber carpets & flooring from rapidly
renewable resources: cork, bamboo, Lyptus
(Weyerhaeuser.com) and Marmoleum (forbo.com) are
some good options
• Local suppliers of bamboo & cork: Longleaf Lumber,
Lumber Liquidators
• When using cork and bamboo flooring, make sure
there are not issues related to binders, substrates &
finishes

Carpeting and Flooring, cont.
• See online sources of recycled & low-VOC flooring
like http://www.greenfloors.com

• Check resources like
http://www.nps.gov/sustain/spop/carpet.htm and
buildinggreen.com for info on sustainable flooring
choices including natural fiber carpet manufacturers &
low-VOC adhesives


Insulation

• Look for formaldehyde-free fiberglass products- e.g.
Johns Mansville (contained in some fiberglass batt
binders)

• Icynene spray foam one of more benign options

• Newer soy-based foams may be good choice too
(see www.biobased.net)


Kitchen counters
• Avoid laminated particleboard (e.g. Formica) unless
on formaldehyde-free substrate & bonded with low-
VOC contact adhesive

• Examples of formaldehyde-free substrates:
Wheatboard, Agriboard (see Bettencourtwood.com)

• Favor solid surface & products that use mechanical
fasteners and don’t require finishing

• Natural stone & recycled glass might be good options

• See Paperstone also (www.bettencourtwood.com)


Exterior Decking
• 100% plastic varieties may be best choice as they are
generally more recyclable than composites (like Trex)
• Pressure treated may be OK but it requires
considerable care to keep it from weathering too
quickly; For a more environmentally preferable option,
borate treated lumber may be a better choice (than
the ‘typical’ ACQ pressure-treated lumber)
• If cedar or redwood is used, make sure it is not from
old-growth forests (use Eastern White Cedar)
• Ipe is a good choice if it is harvested from
sustainably managed forests
• “Raw” linseed oil may be good choice for finishing
(“boiled” contains chemical driers)

Exterior Siding
• Look for durability & ease-of maintenance in addition
to the ‘usual’ criteria

• Ease of installation may affect cost (and your
willingness!) to use product
• There are several composite materials on the market
now that make use of recycled wood fibers
• If cedar is used, make sure it is not from old-growth
forests (see Maibec Eastern White Cedar)

• Masonry finishes generally provide the best longevity
& require the least maintenance


Roofing
• Use high-reflectance roofing to minimize urban heat
islands and cooling loads
• There are many products available that incorporate
recycled materials, like faux slate shingles made from
recycled rubber
• Metal roofs (like standing seam) may be considered
sustainable due to their durability, but they may have
a relatively high embodied energy
• Use of copper roofing/ roof drainage materials may
pose an environmental hazard (to aquatic wildlife)


Some roofing options
• Ecostar- www.ecostarinc.com

• Authentic Roof- www.authentic-roof.com

• Interlock- www.interlockroofing.com

• Naturals- www.naturalsroofing.com

• Natural slate a fairly sustainable option

• Also, cedar shakes if from sustainable wood source
& installed properly

• Note: Some of these given high marks based on
durability more so than recycled content

Additional guidelines for material efficiency

• Employ advanced framing techniques in wood-
framed structures

• Use structure as finish

• Keep it small!

• Use re-used/ salvaged/ surplus materials whenever
possible

• Use locally harvested/ extracted materials whenever
possible


Some Pitfalls in Spec’ing Green Materials

• Uninformed & resistant code and municipal officials

• Products that ‘go away’

• Sourcing materials in a developing market

• “Greening” small-scale projects


Local sources of supply

Alternative Energy Store
www.altenergystore.com

Boston Building Materials Coop
www.bbmc.com

Boston Materials Resource Center
www.bostonbmrc.org

Boston ReStore
www.bostonrestore.org

Green Depot
www.greendepot.com


Local sources of supply, cont.

Pure Home Center
www.purehomecenter.com

Green Source Supply and Design
www.greensourcesupply.com

NE Green Building
www.NEgreen.com


General Resources
GRT: www.greenroundtable.org
Building Green: www.buildinggreen.com
Energy Star: www.energystar.gov
Charles River Watershed: www.crwa.org
US Green Building Council: www.usgbc.org
Renewable Energy: www.nrel.gov
US DOE: www.eere.energy.gov/buildings/
EPA: www.epa.gov/ne/greenbuildings

Residential Green Building Guide:
A Web Source Book for New England
www.epa.gov/ne/greenbuildings

NAHB: Model Green Home Building Guidelines:
www.nahb.org


And don’t forget about NEXUS!

• Upcoming workshops
• Reference library
• Samples library
• Cyber Lounge
• Online resources at nexusboston.com (in the
pipeline)
• Local green building community


Local Resources


THANK YOU
www.greenroundtable.org
info@greenroundtable.org
617-374-3740

The Green Roundtable, Inc. (GRT) is an independent non-profit
organization whose mission is to mainstream green building and
sustainable design and become obsolete. We work toward this goal by
promoting and supporting healthy and environmentally integrated building
projects through strategic outreach, education, policy advocacy and
technical assistance.

Located in downtown Boston, NEXUS
welcomes all to come ask questions,
research topics, and attend tours and
www.nexusboston.com events on green building and sustainable
38 Chauncy Street, Boston design innovation.

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