MATERIALS
OPTIONS, SELECTION CRITERIA
This
section describes some resource efficient and healthy materials
options for each of eight CSI divisions. The materials discussed
are generic, i.e. they are product classes which may be
made by several manufacturers. This is obviously not a comprehensive
listing of all materials for a given use, nor is it an exhaustive
list of materials that may have some special “green
merit”. It is merely a list of some examples of the
type of resource efficient and healthy options which are
available. Please refer to the resource guides and to manufacturers
and dealers for specific information, and be aware that
the variations between specific products may be very large.
DIV.
3 CONCRETE
Making
Portland cement, for concrete, requires much gas and oil
energy, and produces a great deal of carbon dioxide, a greenhouse
gas. Because concrete is such a high mass material, and
such large quantities are used in buildings, it is very
important to consider resource conservation choices.
Resource
efficient options
Fly
ash concrete is available in many regions as an alternative
to conventional mixes. Fly ash is a waste material from
coal burning power plants. It can be used to replace up
to about 30% of the Portland cement in conventional mixes.
It is also mixed with ground blast furnace slag (GGBF),
a waste from metal smelting. Fly ash produces a superior
concrete with excellent finishing characteristics, however
only some types of ash are appropriate for certain applications,
and the proportions are restricted. Seek technical advice
and refer to ASTM Standards.
Recycled
aggregates and lightweight aggregates are available for
some concrete applications. Recycled aggregate may contain
crushed concrete and other masonry waste, or it may contain
crushed glass. Lightweight concrete is made with expanded
volcanic materials such as pumice and perlite in place of
part of the usual stone aggregate. These materials place
less load on structures (particularly when used on wood
or lightweight steel floors), and provide some thermal insulation
value.
Anti
corrosion agents such as epoxy coating extend the life of
steel reinforcement, especially for applications near salt
environments. These have been found to extend the life of
slabs substantially, avoiding repair and replacement costs.
Using
low waste formwork is a final step in resource conservation.
Systems such as modular steel forms, slipforms, preformed
blocks and others can substantially reduce waste material
from concrete forming.
Low
pollution options
Indoor
air pollution emissions from concrete in use are very low,
and concrete is often confined to foundations and concealed
structure where exposure to building air is minimal. The
two exceptions are some concrete additives and some form
release agents. Concrete additives such as water reducers
or superplasticizers should be specified with caution because
these may produce some odors and a risk of skin and bronchial
irritation when fresh. Form release agents are sometimes
made from diesel oil, or other odorous petroleum oils that
will produce emissions in use. Wax or mineral or vegetable
oil based products are available substitutes. This is most
important for interior uses of concrete.
DIV.
4 MASONRY
Masonry
and tile products are made from concrete, clay and various
types of lightweight aggregates. Most masonry products are
installed with mortar made from Portland cement, sand and
lime.
Resource
efficient options
Lightweight
concrete blocks and bricks are available, made with expanded
aggregates such as pumice to reduce weight and add insulating
value. Some brick and block products are available with
waste and recycled contents, such as sewage sludge and ash
from incinerators and coal burning plants. Hollow blocks
are available with waste wood fiber and other recycled content.
Native stone or lightweight cultured stone made from cement
and recycled aggregates are appropriate for some uses.
Glass
block is available with recycled glass content.
Low
pollution options
Air
pollution is a minimal problem with masonry products. If
sealers are needed to repel water, a low-volatile content,
water-dispersed product is safer than a solvent based variety.
DIV.
5 METALS
Steel
is highly recyclable and scrap is valuable. Aluminum is
arguably the most recyclable material used in buildings.
Stainless steel and brass products are alloyed metals and
are recyclable if carefully separated by type. Copper is
a highly valued recyclable.
Metal
plating is also common in building products, especially
in architectural metals, door hardware and office systems
and furniture. Chromium, cadmium, brass and nickel plating
is often done by small electroplating plants which may have
a poor record of pollution control. Emissions such as hexavalent
chromium and cadmium and acid wastes are very environmentally
toxic. Alternatives such as plastic polymer coatings, especially
“powder coatings” have important advantages. See
Div 15, Furniture below. Galvanized metals are zinc coated,
usually by large steel mills, a process which is energy
intensive, but relatively low in toxic emissions.
Resource
efficient options
Steel
is available from US sources with verified recycled content
of 30% or greater. Some steel products such as galvanized
studs, cladding and roofing panels and tube assemblies may
verifiably come from electric “mini-mill” processes
where recycled content claims of 40% or more are justifiable.
Some specialty steel products, such as nails, are produced
by manufacturers who have made an extraordinary effort to
ensure recycled content, and to reclaim waste from their
zinc plating process.
Aluminum
from American sources typically has a verifiable recycled
content between 20 and 30%, usually from consumer product
containers.
Salvaged
steel and aluminum beam and bar sections are also widely
available from scrap dealers. These may be appropriate for
both structural and non-structural uses if verified by a
structural engineer. Architectural metalwork such as antique
iron and brass, lighting fixtures and door hardware are
also readily available from building salvagers.
Low
pollution options
Air
pollution is a minimal problem with metal products. The
only exception is those that may require polishing, cleaning
or repainting in place. See the Finishes Section below.
DIV.
6 WOOD & PLASTIC WOODS
Wood
& plastic woods used in construction and interior finishing
are primarily domestic species. Woods used in furniture,
doors and specialty millwork are often imported tropical
varieties. Appropriate forest management and wood salvage
are keys to more sustainable wood sources in most cases.
It is also possible to find processed woods and wood substitutes
that have the interest and properties of fine woods without
depleting threatened species. Many are available with certification
by independent authorities. These are covered further in
the Furnishings Section below.
Nearly
all plastics are made from non-renewable petroleum feedstocks.
The only exceptions are a few plastic products made from
vegetable oils and plant starch which are relatively benign
processes. Plastic production from petroleum may involve
very hazardous substances such as vinyl chloride (VCM) used
to make PVC. Plastics are sometimes used in building systems
as claddings and panels, but the majority of plastics are
used as interior finishes. These uses are discussed below
in Div. 9, Finishes.
Resource
efficient options
Wood
resource efficiency is one important factor in wood selection.
Engineered wood products and value-added products, such
as ‘I” joists, oriented strand board, laminated
veneer lumber, finger jointed lumber, open web wood joists
and trusses, stressed skin wood panel and wood / steel joists,
make better use of low grade fiber, small diameter trees
and fast growing, less-utilized tree species. Certified,
sustainably-harvested forest products from domestic wood
producers is now available for some products. Databases
and websites are available listing these producers. Certification
of tropical wood products is even more advanced. See the
Finishes Section for more information.
Salvaged
timber and wood products are available from operators who
disassemble old buildings and bridges and then clean, grade
and often resaw the timber. These can be used for structural
purposes (after grading by a qualified person) or for interior
finishing.
Structural
sheathing is also available made from pressed post-consumer
newsprint. This material not only uses a recycled product,
but it adds substantial insulating value and acoustic
absorption
to the wall or roof. In some circumstances, non-structural
insulating sheathing, such as wood fiber or glass fiber
boards, can also be used with steel strap and bracket shear
braces. These eliminate most of the structural sheathing
requirements for walls altogether.
Low
pollution options
Indoor
air pollution emissions from some engineered wood products
are substantial due to the glues used in the manufacturing
process. Those made with exterior type glues (phenolic resins)
and polyurea or isocyanurate adhesives (MDI based) have
the least emissions.
DIV.
7 THERMAL INSULATION & MOISTURE PROTECTION
Depending
on climate, building form and orientation, occupancy and
use, thermal insulation can be an important factor in the
energy performance of buildings. Generally, in practice,
the insulation value required by Title 24 State Energy Code
is used. However higher insulation values through designing
larger cavities, or by using higher performance materials
may occasionally be cost effective. Because this is dependent
on so many factors, it is best to use computer energy simulation
to decide where to insulate and how much, if the project
or renovation is large enough to justify it. Once the desired
insulation value has been determined, it remains to choose
a resource efficient and healthy material.
Resource
efficient options
Mineral
fiber insulation (rockwool) is made primarily from mineral
waste and mill slag. It is available in loose fill form,
batts and rigid boards, and can be used for most applications,
including outdoor and below ground locations.
Glass
fiber insulation is now available with 40% or more, post
consumer recycled glass content from cullet (waste glass
from recycling). It is available in loose fill, batt and
rigid boards.
Cellulose
thermal insulations and acoustic sprayed coatings contain
at least 70% post consumer paper waste. These are available
only in loose fill form. Walls can be insulated using the
“blown in batt” system installed with a high-pressure
blower and a containment screen. If installed to density
specifications, it will not settle after application. Horizontal
spaces are filled with a low-pressure blower. Some systems
use a small amount of moisture to encourage stabilization.
Sprayed cellulose systems are designed for acoustic and
fire retardancy (often for metal structures) and may contain
mineral fiber.
Foamed
polystyrene insulation is available with post consumer recycled
contents from recycled fast food containers and hot drink
cups. Expanded types are made with a steam process and a
non-CFC gas. Extruded types are higher performance and are
now made with HCFCs, which have far less ozone depleting
potential than the CFCs used previously. New extruded products
containing no HCFC’s are now becoming available.
Urethane
foams are high performance insulations available as rigid
boards or sprayed-in-place systems. These also were once
made with CFCs and are now made with HCFCs. One manufacturer
has developed a sprayed-in-place system expanded with harmless
CO2 (Icynene).
Vermiculite
and perlite are naturally occurring minerals that can be
used in insulating plaster mixes, and in loose fill applications
such as filling cores of masonry walls.
A
“spray-in-place” foamed silicate insulation, made
from sodium silicate and magnesium oxychloride, is available
for use where fire retardancy and material safety are critical.
This is used for cavity fill applications and some surface
uses, but it is very moist when applied and can take several
days to dry.
Reflective
film radiant insulations can be used effectively to reduce
the “radiant component” of energy transfer, such
as excess heat gain from the sun. They can be particularly
useful for reducing cooling loads in commercial buildings
in sunny climates. These are made from aluminum foil and
metallized plastics and are usually installed in a roof
cavity with an adjacent air space.
Low
pollution options
All
common thermal insulations have some potential health risk
and will require care in handling. They must be applied
in such a way that they can be completely contained or isolated
and cannot enter the building or air handling system. Thorough
clean up after handling is also critical. Mineral fibers
and glass fibers are now recognized as possible carcinogens
and must be handled with respirators and protective clothing.
Cellulose fiber is relatively safe, but it contains
borates and sulfates as fire retardants and stabilizers
which are highly irritating, so that installers and building
occupants must also be protected. This is even more important
for sprayable cellulose insulations that contain mineral
fiber. Vermiculite and perlite dust are also hazardous to
inhale and must be handled with caution. These natural mineral
products must be certified asbestos-free.
All
plastic insulations release some gases such as styrene,
and are flammable, producing toxic gases when burning. Codes
require a non-combustible covering over them, and may not
allow them at all in some uses. These are primarily useful
for exterior applications. Cutting with a hot wire releases
toxic gases and should be avoided on building sites.
Cladding
& Roofing
Cladding
and roofing are very important for building longevity. The
materials should be appropriate for the climate and application,
and the best quality material allowable within the budget
should be chosen. After durability, the second most important
factor is recyclability.
Resource
efficient options
Metal
panels such as galvanized steel and enameled or anodized
aluminum are appropriate for pitched roofs and cladding.
They have the merit of using very little material, and they
are durable and recyclable.
Composite
shingles, tiles, and panels made from a variety of fiber
reinforced cement products (some coated with plastics, enamels
or thin metals) are also available for pitched roofs and
cladding. These have the merit of durability, and some contain
recycled content. Though they are not recyclable, these
are a good choice for durability and resource efficiency.
Stucco
is a resource efficient and durable finish where it is protected
from moisture damage by good detailing. Acrylic modified
stucco is less massive and can be installed on exterior
insulation board, adding to thermal performance.
Where
shingles are chosen for roofing, higher quality asphalt
shingles and fiberglass matrix shingles are a moderately
durable option. Some may be available with recycled content.
For
flat roofs, torch-on, or cold process built-up roofing has
some important advantages. It is fairly durable and repairable,
and though recycling systems are not in place, it is relatively
easy to remove. An inverted roof design using a ballasted
insulation layer over the membrane has advantages because
the membrane is better protected from weather and damage.
Flat and shallow pitched roofs can also be prepared with
drainage mats and topsoil to grow grass if the structure
allows. This “green roof” helps to control rainwater
runoff and adds insulation value to the building. It also
provides habitat for birds, butterflies etc.
Low
pollution options
Roofing,
due to its location, is usually not an important contributor
to indoor air pollution. However hot mopped asphalt roofing
releases extremely high levels of air pollutants during
installation and may be restricted in some urban areas due
to smog contributions. It is also a health risk to installers.
Sealants
Sealants
are used in small quantities and are therefore not very
important resource efficiency concerns. However they are
important health concerns, because many are solvent based
and toxic.
Resource
efficient options
The
sealant with the best service life will always be the best
choice, regardless of material type, considering the high
labor cost of replacement and the potential for costly
building damage.
Low
pollution options
Generally
sealants used outside the building are not much of an indoor
air pollution concern. Those used indoors in any quantity,
such as caulking for door and window installation, should
be carefully selected using health evaluations from material
safety data sheets. Acrylics, silicones, and siliconized
acrylics are typically the safest to handle and have the
lowest solvent content. Quantities of solvent based products,
such as common “acoustic caulking”, butyls and
urethanes, should be avoided indoors.
DIV.
9 FINISHES
Interior
finishes are the most important materials category for reducing
indoor air pollution load. They are often the most important
products from a resource conservation perspective also,
because they are the ones that experience the most wear,
and are replaced regularly during renovations. Because office
interiors are altered so often, there is not always a good
argument for the most durable finishes. In some cases it
is better to emphasize low toxicity, recycled content and
reusability/recyclability.
Gypsum
Gypsum
products are the most common interior panels used due to
their fire retardancy and low cost. However limitations
on dumping gypsum in landfills may apply in some areas.
Gypsum recyclers, where available, will receive clean gypsum
waste from construction and possibly demolition.
Resource
efficient options
Some
gypsum board manufacturers can verify at least 10 to 15%
recycled content. Gypsum is highly recyclable if not contaminated
with paint, adhesives etc., and the paper facing can be
made with recycled paper. One recent innovation in gypsum
products is the fibergypsum process. This board, now available
in the US, has no paper facing but contains recycled wood
and paper fiber, and perlite inside the board. It is very
strong and scratch-resistant, and should be considered for
high wear areas such as commercial and institutional buildings.
Low
pollution options
Gypsum
products themselves are minor sources of indoor air pollutants,
though the paper facing and any adhesives can be sources.
Gypsum surfaces are also potent “sinks”, i.e.
they absorb odors and then release them. In the construction
phase it is the installation adhesives, sealers, paints
and caulkings that are the main concerns. See these sections
below.
Wood
& plastic
Wood
and plastic, engineered and composite panels are important
components of interiors. They can offer resource efficient
design, and they can have recycled content. However the
adhesives and sealers used in manufacture and installation
are indoor air pollution sources.
Resource
efficient options
Hardboards
are durable and resource efficient. These are made with
wood fiber pressed and heated to form panels. No adhesive
is usually needed because the natural lignin in wood binds
the fibers. They are reusable if installed so that they
can be easily removed. One US company now has a process
for fiberizing wood demolition waste so that it can be used
in hardboard products.
Particleboard
and MDF (medium density fiberboard) panels are pressed from
sawdust and small chips and fibers bound with glue. They
can use low-grade woods and sawmill waste in their manufacture.
These are resource efficient products, but must be chosen
carefully for low pollution potential. See the health discussion
below.
Low-density
fiberboards made from paper and wood fiber are also resource
efficient. Most processes use no glue. They are used as
acoustic panels, underlayment, tackboards etc. They are
available made from 100% recycled newsprint. They are not
now being recycled.
Veneered
wood panels, such as oriented strand board with hardwood
facing, are resource efficient choices for interior finishing
work. These are used for cabinets and millwork and can offer
wood grain surfaces while conserving wood. If installed for
easy removal, these have good reuse potential.
Recycled
plastic panels made from consumer product waste are available
for interior uses such as toilet partitions and functional
work tops. These have a good reuse potential.
Some
vegetable oil based plastics are available in both flexible
and rigid types. They can be colored and filled with minerals,
metal shavings, or other plastic waste and wood fiber giving
them a large range of texture and color possibilities. If
installed for easy removal, these also have good reuse potential.
Fiber
reinforced cement boards made with recycled fiber are a
resource efficient choice. They are very durable products
and can be used as substrates for tile and decorative finishes.
In some installations they can have good reuse potential
if designed for easy removal.
Low
pollution options
Engineered
wood products made with exterior glue (phenol formaldehyde)
have very little formaldehyde emissions. Products which
have been stabilized by ammonia treatment or other methods
are also low emission. One manufacturer offers “formaldehyde
free” products made with isocyanurate adhesive which
are the lowest in air pollution emissions of all glue-bonded
boards. The HUD low formaldehyde emissions standard label
should be on these products. Those products which meet the
more rigorous European E1 standard are even lower in emissions.
The cement based and vegetable oil plastic composites are
generally very low in pollution potential.
High
pressure laminates are surface materials made by laminating
paper and colorants together with melamine (phenolic) resin.
They are a relatively resource efficient use of plastics
because a very small quantity of materials suffices to produce
a durable surface.
Resource
efficient options
There
are no manufacturers known at this time with substantial
recycled content in their products. There are some who have
made important process improvements, such as waste-to-energy
and heat recovery systems which exceed industry norms. Their
products may have a small resource efficiency advantage
over others.
Low
pollution options
These
products are low emission due to the high temperature curing
process and the inherent chemical stability of the materials.
However the dust from cutting and the emissions from glues
used for installation can be quite important. This work
should ideally be done in a shop off the premises, and the
adhesives chosen for safe handling characteristics. See
the Adhesives section below.
Ceramics
& terrazzo
Ceramics
and terrazzo are among the most durable and low emission
interior finishes. Glazed or sealed products do not adsorb
odors and pollutants, are easily cleaned and resist abrasion
and wear. Though they are costly to buy and install, their
life cycle cost is among the lowest of all finishes for
some applications, due to their long life and minimal maintenance.
The only important air pollution factors are the setting
method, the grout and any sealers required to protect unglazed
surfaces.
Resource
efficient options
Using
local or regionally manufactured ceramics reduces the high
transportation cost.
Some
tile is available with recycled content (up to 70%), such
as scrap glass and feldspar waste from mining. These have
important resource efficiency merit. Some manufacturers
also have added heat recovery, water recovery and clay mine
restoration measures to their operation which exceed industry
norms.
Tile
packaging is also an important item. Look for manufacturers
that use simple systems with recycled contents, such as
cardboard.
Terrazzo
made with cement and crushed stone is also resource efficient.
Low
pollution options
Cement
mortars, usually modified with acrylic additives, are the
safest to handle for tile setting. These also have the best
performance for most applications. All plastic adhesives
contain some solvents and will contribute to indoor air
pollution. Where adhesives and caulking must be used, such
as for cove bases and flexible joints, a low solvent content
product such as an acrylic can be chosen. Cement based,
cellulose based and acrylic modified grouts are very safe
and low emission. Glazed tile and high-fired tile usually
do not require sealers. If a porous tile is chosen, the
safest sealers are the low-volatile, acrylic or water-dispersed
silicone types. Sealers containing hazardous solvents will
contribute to indoor air pollution.
Wood
flooring
Wood
flooring can be used in offices, reception areas, stairs
and meeting rooms. There are many resource efficient types
of wood flooring, including salvaged, laminated and veneered
products. The most important air quality issues are the
installation method and the finish.
Resource
efficient options
Salvaged
solid wood flooring is widely available. These are high
quality materials available for a very modest cost, however
the installation is more expensive than for new material
due to the extra labor for fitting and refinishing. It also
requires sanding and refinishing on site.
Among
new wood flooring materials there is now a wide range of
veneered and laminated products which have a plywood or
MDF core with a hardwood surface. These are usually prefinished
at the factory with a very durable, low-maintenance finish.
These are a resource efficient choice, but are less repairable
than solid wood.
Domestic
hardwoods such as oak, maple, birch and ash, and imported
species such as Australian eucalyptus and Scandinavian beech
are some varieties which are most likely to be from sustainable
sources. Tropical hardwoods should be carefully researched
using the wood publications and databases listed in the
Resources Section of the Materials Chapter.
A
steel track system using wedges to hold the flooring in
place, or a “floating system”, using edge gluing
where necessary makes wood floors easy to remove. A nail
down system is also salvageable, but with some loss of material.
A glue down system is probably the least salvageable, but
it is required for parquets.
Low
pollution options
The
factory prefinished products have substantial air quality
benefits because no sanding and finishing is done on site.
If sanding is done on the premises, the area must be carefully
isolated, including sealing off the doors and HVAC system,
and using temporary fans. Final cleanup with a high performance
HEPA filter vacuum is recommended. For finishing on site,
the water dispersed urethanes (actually urethane/ acrylic
blends), with low-volatile content have the least emissions
of common finishes. Those with “crosslinker” additives
are the most durable. Hardening oils, solvent varnishes
and acid cured varnishes have prolonged emissions of pollutants.
If edge gluing is required, white carpenters or woodworkers
glue is a low toxicity product. If glue-down methods are
required, such as for parquet, a low-volatile flooring adhesive
can be used.
Resilient
flooring
Resilient
floorings, such as vinyl, rubber, linoleum and cork have
merit for their easy maintenance, and some types are very
durable. Some materials have renewable contents, and others
have recycled content. In terms of air quality, there are
important distinctions between material types, installation
methods and maintenance products.
Resource
efficient options
True
linoleum is made with renewable materials (linseed oil,
cork, wood dust and jute), as are cork products. Linoleum
is extremely durable.
Recycled
rubber tile and sheet goods are also available made with
waste tires. These are good, resource efficient choices
for heavy traffic and utility areas.
Vinyls
are also easily maintained and durable. Some may soon be
available with recycled plastic contents.
Low
pollution options
All
resilient flooring products produce some air pollutant emissions;
so do their setting and maintenance products. Some manufacturers
can provide comparative emissions data that will aid in
selection. In some applications, interlocked rubber tiles
and heavy linoleum can be laid without adhesive. If adhesive
is required, see the Adhesives section below. Linoleum has
a mild antiseptic effect that reduces sour odors from urine
and food spills, making it a good choice for kitchens, cafeterias
and washrooms.
Maintenance
products are also significant pollution sources. Flooring
with sealed “low maintenance” surfaces should
be preferred, both for reducing maintenance costs and the
use of cleaners and waxes.
Carpet
& underpad
Carpet
and underpad are among the most important interior products
to consider for resource efficiency and pollution potential.
They are high maintenance and high turnover materials with
known air pollutant emissions. Fortunately several products
are now available with recycled content, and with inherent
lower pollution potential and lower maintenance requirements.
Resource
efficient options
Polyester
and nylon blended carpet is available with recycled content
from PET soft drink containers. These have similar properties
to other polyesters.
Wool
carpet is also available in commercial, high density, low
pile lines. The wool face fiber is a renewable material
with inherent fire resistance and good durability for light
commercial uses.
Releasable
carpet tile and roll carpet systems can be moved from low
wear areas to high to extend the life of the floor. They
are also easily removed and replaced during renovation.
The lowest maintenance carpets are typically the low pile,
dense loop and needlepunch types which trap the least soil
and show wear the least.
Carpet
recycling is an industry priority today due to the large
quantity sent to landfills, where it will not easily decompose.
The major obstacles are recyclability of the face fiber
itself, the added colorants, and separation of the different
materials in the product. Carpets made from fewer materials
will require less separation for recycling. Fully recyclable
carpets are just now becoming available.
Carpet
pad is made from sponge plastics and rubber, as well as
woven and non-woven textile fibers. Rubber pad made from
recycled tire rubber is a resource efficient choice. It
is a dense and durable product with a very long life expectancy.
Fibrous pad is also available in commercial grades made
from recycled synthetic and natural fiber from textile mill
waste.
Low
pollution options
The
way carpet is constructed is one important factor in the
air pollutant emissions from the product. The vast majority
of carpet is made by pressing the face fiber into a polypropylene
mat, and then gluing it in place with a synthetic latex
resin. The synthetic latex is a source of air pollution,
including 4 PC (4 Phenylcyclohexene), an irritant which
is implicated in several cases of sick building syndrome.
One method of low emission carpet construction is to eliminate
the latex bond through “fusion bonding”. This
type of carpet has a sponge plastic backing into which the
face fiber has been heat welded. It is a good choice for
low indoor pollution potential. Needle punched carpets which
are very low pile and mass are also made without latex.
Among all other latex bonded carpets, including wool products,
there is wide variability in emissions. A few manufacturers
have made a great effort to provide a low emission product,
and some of these can provide full test results, listing
VOC emissions at different time periods.
Airing
out new carpet has often been recommended as a pollution
reduction measure, but the evidence is not strong for the
effectiveness of this method. Though this will help for
some of the short term volatile contents, and will reduce
odors picked up (adsorbed) in manufacturing and storage,
other carpet contents are semi-volatile and will produce
emissions for many months.
Finished
concrete flooring
Finished
concrete flooring is an integral system of slab and finish,
produced by adding colorants and sealers to the topping
concrete either before or after it cures. The concrete is
often stamped with tile patterns and grid lines that also
control cracking. It is a durable and low maintenance finish.
Resource
efficient options
Finished
concrete may be appropriate for areas that would otherwise
be tile or terrazzo. Systems with integral color added to
the entire topping layer are more resistant to damage, and
less likely to require recoloring, than systems which are
dyed after placing the concrete. Proper sealing and waxing
will ensure a long service life.
Low
pollution options
Finished
concrete is inherently low emission. The choice of sealers
is the main concern. Water- dispersed, acrylic sealers and
waxes meeting low volatiles standards are the safest.
Painting
Painting
is only a moderate resource use item since so little material
is actually used. It is, however, an important indoor air
pollution and toxic waste consideration. Fortunately volatile
emissions from liquid coatings such as paint tend to be
short term, i.e. they decline to a very small fraction of
the wet emission rate within a few days or weeks. The most
toxic emissions from paints and coatings are usually evaporating
solvents and a wide variety of volatiles released by oxidation.
These volatiles are produced not only by solvent-based paints,
but also water-based formulations. In fact water based paints
may contain up to 12% solvents, though some new formulations
contain very little. Today it is not necessary to use paint
containing hazardous solvents for most interior applications.
Water borne acrylics are clearly preferable to alkyds (solvent
based oil paints) for handling safety, and they are highly
durable and produce no solvent waste.
Resource
efficient options
Several
companies in the US are now providing recycled paints made
by mixing remainders and returned products together by color.
These are generally good-quality acrylic latex paints, suitable
for moderate duty interior use; however, the color range
is quite limited.
For
exterior use, or some industrial applications, it may be
necessary to use solvent-based paints. Where solvent paint
is required, the painters should be required to recycle
solvent. Building managers should eventually dispose of
remainder paints that have been saved for touchup and renovations.
These paints can be sent for recycling, either through municipal
programs or through paint suppliers.
Low
pollution options
The
first priority with paint selection is to avoid products
that contain lead, mercury, hexavalent chromium and cadmium.
Though regulations have nearly eliminated many toxic components
from consumer paint lines, industrial and commercial paints
may still contain them. Check the MSDS’s first, because
all of these toxic contents must be disclosed. The next
priority is to select those paints with the least volatile
emissions. These are exclusively water dispersed acrylic
and latex products. Those that meet California and New Jersey
“zero VOC” standards have the least emissions.
Those which meet listing programs such as Green Cross, the
Canadian Environmental Choice Program or the German Blue
Angel Program may also be low emission, though the standards
may not be as rigorous as the “zero VOC” standard.
Adhesives
for construction and flooring uses are also hazardous waste
and indoor air pollution concerns, similar to paints above.
Similar low pollution selection can be done. There are a
few US companies providing lines of low VOC adhesives, sold
as environmentally safe, “zero VOC’s” or
“low toxicity”.
Ceiling
tile
Ceiling
tile is the most common ceiling finish in commercial and
public buildings. Due to its large area, its potential for
disturbance during renovation, and its contact with HVAC
systems, it is an important product to consider for air
quality and resource efficiency.
Resource
efficient options
Tile
is made from wood fiber, including recycled material, and
often mineral fiber with added clay or gypsum fillers for
fire retardancy. It is then painted. Some manufacturers
list tile with recycled content, though none with post-consumer
contents are known at this time. Tile is reusable and paintable,
and should last many years if not handled excessively.
Low
pollution options
All
tile collects dust and adsorbs odors. Tile with mineral
fiber contents may also begin to shed hazardous fiber if
disturbed, or as it deteriorates. Both problems are a particular
concern where the ceiling is used for a return plenum to
carry air back to HVAC air handlers. If this type of return
system is used, the tile should be checked for damage and
the plenum space occasionally cleaned with a high performance
vacuum. If possible, in new and renovation design, HVAC
returns should be ducted instead of risking contamination
by debris in suspended ceilings.
WARNING:
OLDER BUILDINGS BUILT OR LAST RENOVATED PRIOR TO 1976 MAY
CONTAIN ASBESTOS INSULATIONS AND LEAD PAINT PRODUCTS. THESE
ARE SERIOUS HAZARDS TO OCCUPANTS AND TRADESPERSONS DURING
RENOVATION OR DEMOLITION. THESE MATERIALS ARE ALSO HAZARDOUS
AS THEY DETERIORATE. A professional specialist should be
engaged to identify and manage these hazards where they
occur. Your regional EPA office or State Department of Health
Services can provide advice and listings of qualified consultants.
DIV.
10 SPECIALTIES
There
are several panel systems for office partitions and non-structural
interior uses which allow changes to floor plans without
major demolition and waste. Though these cost more than
lightweight steel framing and gypsum panels built on-site,
they are reusable and allow rapid changes to be made with
minimal disruption. They also have many recyclable components
when they are no longer useful. Usually referred to as “demountable
systems”, these have steel or aluminum track at the
top and bottom, holding gypsum panels which lock into place.
Door modules, glass, different surface finishes and several
other options are available. The manufacturers claim typically
less than 10% materials waste when relocating them. Used
systems can be purchased, and matching components traded
between departments or buildings, or stored for future use.
These have important resource efficiency merits.
DIV.
12 FURNISHINGS
Though
not a part of buildings, furnishings are an important resource
efficiency and indoor air quality consideration for organizations.
They represent a major cost and maintenance component for
interiors, and are key to workplace satisfaction and comfort.
Resource
efficient options
The
most resource efficient option for furniture is to repair
any good quality items currently owned by the organization.
Good quality used office furniture can also be purchased
from office furniture suppliers which exist in every city.
A few large office furniture manufacturers and several resale
operators also now offer reconditioned furniture as a purchase
or lease option. These are usually classic, durable lines
that have been bought back or returned from leases, and
have been recovered, refinished and serviced.
Steel
glass and solid wood furniture has significant resource
efficiency and recyclability merits. It also has minimal
indoor pollution potential.
Metal
coating systems and wood finishes are important environmental
issues with furniture. “Powder coated” metal finishes
are an environmentally friendly substitute for painting
and plating, using dry powder polymers applied to the metal
and then fused with heat. Powder coated finishes are harder
than many paints, and can actually rival plating for durability.
For woods, factory applied and cured coatings such as urethanes
have minimal emissions, and the manufacturing plants minimize
dust release and recycles solvent.
Tropical
hardwoods are common in office furniture, both as solid
components and veneers. It is well known that rare and prized
woods such as rosewood, teak and ebony are now in short
supply, and substantial forest destruction takes place to
extract them. Tropical hardwoods can be researched using
the wood guides listed in the Resources Section of the Materials
Chapter. Some conscientious office furniture manufacturers
are already using these guides, and are offering substitute
woods that enhance forest based economies of producer nations.
Another
wood option is manufactured or synthetic hardwood. These
are typically northern hardwoods dyed and machined to create
beautiful and unique wood finishes. Several are listed in
the databases and publications in the Further Resources
section of the Materials chapter.
Upholstery
foams used in chairs are generally high-density urethane
products. These were once manufactured with ozone depleting
CFC’s, but are now made with safer HCFC’s. Chairs
should carry labels certifying that the foams are non-CFC.
HCFC’s are also due to be phased out from upholstery
foam before year 2000.
Low
pollution options
The
main air pollution potential from furniture is due to glue-bonded
wood products, soft plastics, fabric treatments and finishes.
Some office furniture manufacturers have done emission testing
on their systems and can provide the data. Fabric coverings,
foam fillings and fabric-covered acoustic panels are also
dust collectors and adsorb odors. Where these are in use
they can be cleaned regularly to minimize the problem.
