Recycled content is the most immediately noticeable,

environmentally beneficial feature of a product.

Preference for a design, product or service based solely on

this one attribute, however, can be misleading. The

Environmental Protection Agency (EPA) and other

environmental experts recommend that a comparison of the

environmental properties of competing products employ a

life-cycle analysis.

A life-cycle analysis is an appraisal of the environmental

impacts connected with a product or service through an

examination environmental traits of the product during the

following stages: pre-manufacturing; manufacturing;

distribution/packaging; use, reuse, maintenance; and waste

management. In other words, life-cycle is a “cradle-to-

grave” assessment.

Responding to the recommendation of environmental experts,

the North American Insulation Manufacturers Association

(NAIMA) has developed this brochure outlining the various

life-cycle characteristics that specifiers should consider

in determining the most relevant attributes of an

environmentally preferable insulation product.

PRE-MANUFACTURING STAGE

An analysis of the pre-manufacturing stage should reflect

environmental effects associated with all pre-manufacturing

activities including raw material acquisition and

intermediate processing. For example:

Fiber Glass Insulation Is Made From Sand or Recycled Glass

• Sand is a “rapidly renewable resource,” one that will

  always be in plentiful supply. Thus, the use of sand as

  a raw material does not impose any impact on a non-

  renewable natural resource.

• Recycled plate and bottle glass is considered a

  secondary raw material. When used as a raw material,

  recycled glass is transformed into a product that saves

  energy and reduces pollution.

Slag Wool Insulation Is Made from Blast Furnace Slag

• Slag wool insulation uses raw materials derived from a

  secondary source – blast furnace slag – and does not

  deplete any natural resources.

Caution: Some Secondary Materials May Indirectly Deplete

Natural Resources

When a secondary raw material is used, consideration

should be given to whether its use may indirectly

accelerate the depletion of a natural resource. For

example, by using recycled newsprint for insulation, the

manufacturers of cellulose insulation have removed

newsprint from the recycling stream and forced printers to

rely upon virgin, rather than recycled, newsprint. This

translates into a further loss of renewable raw timber

resources.

MANUFACTURING STAGE

Energy Consumption vs. Energy Saved

While the production of fiber glass and slag wool

insulation is energy-intensive, manufacturers have improved

energy efficiency substantially over the last decade by

using increasingly more sophisticated technology. It is

important to note that the energy used in production is

immediately replenished through the use of the final

product.

An evaluation of the manufacturing process should measure

inputs (such as energy consumption) and outputs (such as

air and water effluents).

Inputs

• Nearly 33 trillion Btu of energy are consumed by fiber

  glass and slag wool producers annually to manufacture

  insulation products; however, insulation produced each

  year saves about 400 trillion Btu annually.

• All insulation products installed in U.S. buildings save

  consumers about 12 quadrillion Btu annually or about 42

  percent of the energy that would have been consumed with

  no insulation in place. Twelve quadrillion Btu is

  almost 15 percent of the total national energy used; it

  is enough energy to supply the total energy requirements

  of Florida for 4 years.

• A typical pound of insulation saves 12 times as much

  energy in its first year in place as the energy used to

  produce it.

Outputs

Most fiber glass and slag wool manufacturing facilities

utilize a closed-loop water recycling system making waste

water effluent discharges nonexistent. While manufacturing

facilities emit certain air pollutants, both the fiber

glass and slag wool industries will soon adopt maximum

achievable control technology (MACT) to help limit the

amount of air pollutants emitted into the atmosphere.

These new controls will supplement existing controls that

already substantially reduce potential air emissions from

the manufacturing process.

lutants emitted into the atmosphere.

PACKAGING AND TRANSPORTATION

Total Product Volume

A life-cycle analysis should consider the total product

volume it takes to accomplish an assigned task. For

example:

• To insulate a typical 2,500 sq. ft. two-story home with

  an R-value of R-30 in the attic, and an R-13 in the

  exterior walls, requires 2,695 pounds of cellulose

  insulation, which is three times more material per house

  than fiber glass.

• Because fiber glass insulation products are more compact

  than other insulation products, the packaging for fiber

  glass products requires significantly less material.

  For example, to insulate a typical 2,500 sq. ft. house

  requires 30 packages of fiber glass compared with 109

  cellulose insulation packages.

RECYCLABLE PACKAGING

Fiber glass and slag wool manufacturers now use recyclable

plastic packaging as a way to conserve resources.

Packaging is often coded for material identification, and

can be recycled in areas where facilities exist.

LESS ENERGY USED TO TRANSPORT MATERIALS

Due to the compact nature of fiber glass and slag wool

insulation, combined with compression packaging, the actual

amount of packaging material has been reduced and the

result is less scrap at the job site and in the waste

stream. Since fiber glass and slag wool insulation

products are so highly compressed, more insulation can be

shipped in each truck and the result is a reduction in the

energy required for transportation.

PRODUCT CHARACTERISTICS

Judging a Product’s Ability to Perform Its Intended

Function

Due to the compact nature of fiber glass and slag wool

insulation, combined with compression packaging, the actual

amount of packaging material has been reduced and the

result is less scrap at the job site and in the waste

stream. Since fiber glass and slag wool insulation

products are so highly compressed, more insulation can be

shipped in each truck and the result is a reduction in the

energy required for transportation.

R-Value

R-value is resistance to heat flow — the higher the R-

value, the greater the insulating power. Thickness of

insulation is only one factor that determines its R-value.

In fact, insulation should always be specified by R-value,

not thickness.

Fiber glass and slag wool insulations are high

performance products that yield a high R-value per inch,

which varies depending on density. The overall R-value

installed in the building is the measurement to look for,

not the R-value per inch.

Settling

A product’s R-value should not deteriorate over time. If

an insulation product settles, the installed thermal

performance is directly impacted. Therefore, specifiers

should consider a product’s ability to resist settling and

maintain its thermal performance for the life of the

building.

Water Absorption

In general, insulation will lose R-value when wet. Some

insulation is made of material that does not wick up and

hold water, but other insulations will absorb water and may

mat down causing permanent reduction in the thermal

performance.

Corrosion and Flame Resistance

Certain chemicals routinely applied as a fire retardant to

most cellulose insulations can cause the corrosion of pipes

and wires under some conditions. Flame resistance is

another performance feature that should be weighted in

selecting an insulation material.

• Fiber glass and slag wool insulations are naturally non-

  combustible and remain so for the life of the product.

  Fiber glass and slag wool require no additional fire

  retardant chemical treatments.

• Cellulose insulation is made of ground-up or shredded

  newspaper, and wood-based products are naturally

  combustible. To protect against fire hazards, cellulose

  insulation is heavily treated with fire retardant

  chemicals prior to installation. Typically, 540 pounds

  of fire retardant chemicals are added to cellulose

  insulation used to insulate a 2,500 square foot home.

  The Consumer Product Safety Commission (CPSC) mandates

  that cellulose packages carry a fire hazard warning for

  consumers and users.

USE, REUSE AND MAINTENANCE

Fiber Glass and Slag Wool Insulations are Reusable

Most modern buildings are subject to expansion, remodeling, or

some other type of renovation during their lifetime. Because of

this, the reusable nature of a product is a key factor in the

life-cycle analysis. For example:

• Fiber glass and stag wool batt insulation can be removed

  easily and actually put back in place. In other words,

  they are reusable. This is not true of all insulation

  materials. Certain foams or aerated concrete require

  extensive chiseling to remove the insulation. Such an

  operation can result in loss of building materials that are

  damaged in the removal process and loss of the insulation

  itself.

• Fiber glass and slag wool insulation require no

  maintenance. This eliminates the expenditure of energy or

  natural resources associated with maintenance operations.

• In addition, fiber glass and slag wool insulation last for

  the life of the building if undisturbed. A long life

  expectancy saves money on replacements and retrofits, and

  also ensures that no additional material is entering the

  waste stream.

RECYCLED CONTENT

High Recycled Content

Not only do fiber glass and slag wool insulation products save

energy, they use a high percentage of recycled material which

further helps the environment. In addition to reducing demand

on virgin resources, using recycled materials saves landfill

space by diverting materials from the solid waste stream, and

reduces the energy used, and pollution emitted, during the

manufacturing process. Recent surveys on the amount of recycled

content in fiber glass and slag wool insulations include the

following facts:

Fiber Glass

• The amount of recycled glass used by fiber glass insulation

  manufacturers in 1996 was over one billion pounds.

• The use of recycled glass resulted in a savings of over 27

  million cu. ft. of landfill space at a density of 37

  lbs./cu. ft. (semi-crushed glass).

• Many fiber glass insulation products now contain up to 40

  percent recycled materials, depending on the plant in which

  they are produced.

• Fiber glass insulation manufacturers recycle more material

  by weight than any other type of insulation used the

  building and construction sector.

• According to the Glass Packaging Institute, fiber glass

  insulation is the largest secondary market for recycled

  glass containers.

Slag Wool

• The amount of recycled blast furnace slag used by slag wool

  insulation manufacturers in 1996 was more than one billion

  pounds.

• The use of recycled blast furnace slag resulted in a

  savings of over 16 million cu. ft. of landfill space.

• The slag wool industry consumes a significant portion —

  approximately 6 percent — of the blast furnace slag

  produced in the United States that might otherwise end up

  in a landfill.

• The industry estimates that over 90 percent of their slag

  acquisition is new slag purchased directly from

  manufacturers. The remaining 10 percent is mined from

  waste disposal sites.

HEALTH ISSUES

Tested vs. Untested Products

An important feature of a life-cycle analysis is whether a

product or service poses human health risks. The EPA has listed

carcinogenicity and irritancy as attributes that justify

labeling a product as a human health risk. Consumer products of

all kinds currently carry these labels. Just because one

product has been thoroughly tested for carcinogenicity and

irritancy (e.g., fiber glass and slag wool insulations) and

another has not (e.g., cellulose insulation) should not imply

environmental preference for the non-tested product. Indeed,

the failure of a manufacturer adequately to test its product

should be a critical factor in determining that a product is not

environmentally preferable.

When evaluating alleged health hazards of a product, specifiers

should distinguish: a) between products that impose potential

risks in the manufacturing process, but not in use of the final

product, and b) between those products which pose risks in both

the manufacturing process and the final use of the product.

Fiber Glass and Slag Wool Are Safe to Manufacture, Install and

Use

Fiber glass and slag wool manufacturers have funded over 50

million dollars of research at leading independent laboratories

and universities in the United States and abroad. In the past

ten years, there have been a number of comprehensive reviews of

research on the health aspects of fiber glass and slag wool by

U.S. and international organizations. These reviews have

concluded that fiber glass and slag wool have not been shown to

cause cancer or nonmalignant diseases in humans. Indeed, the

weight of scientific evidence demonstrates that fiber glass and

slag wool insulations are safe to manufacture, install and use

when practical recommended work practices are followed.

WASTE MANAGEMENT

Recyclable

Another factor of importance in a life-cycle analysis is whether

the product is recyclable. As mentioned previously, fiber glass

and slag wool insulations are reusable after the initial

installation and, therefore, are recyclable. Fiber glass also

has the capacity to be reclaimed from demolition debris and

recycled into new products. In fact, fiber glass trimming at

manufacturing facilities is routinely placed back into the mix

and converted into usable products. Not all insulation products

possess such a characteristic.

mmended work practices are followed.

SAFEGUARDING THE ENVIRONMENT

Fiber glass and slag wool insulation products make buildings

more energy efficient, reducing the amount of fossil fuel

combustion needed to heat and cool homes, businesses, and

factories, which, in turn, decreases the amount of sulfur

dioxide and carbon dioxide emitted into the atmosphere.

Because carbon dioxide is one of the principal “greenhouse

gases” contributing to global warming, and sulfur dioxide is the

major component of acid rain, insulation plays a significant

role in protecting the environment. For example, insulation

currently in place in U.S. buildings reduces the amount of

carbon dioxide emissions by 780 million tons each year.

The fiber glass and slag wool industries are also

safeguarding the integrity of the ecological balance by

manufacturing products whose components may be recovered and

reused at the end useful life of the product. Fiber glass and

slag wool insulations sustain the energy life-cycle by

transforming what might otherwise be waste products into

insulation material that can be used over and over again.

Indeed, from a life-cycle perspective, fiber glass and slag

wool insulation offer tremendous benefits to the environment and

complement policies which promote environmentally preferred

products.