Construction Waste Management (CIWMB)
SUMMARY
Integrated waste
management encompasses prevention of waste whenever possible, reuse or
recycling whenever practical, disposal only of what is left, and buying
products made out of materials that people recycle. This section touches
briefly on some considerations when developing a waste management plan, and
ideas to help prevent waste generated on construction sites.
WHY THIS IS IMPORTANT
If there weren’t
already enough reasons, the State of California takes waste reduction so
seriously there is a law against maintaining the status quo. In 1989, the
California Integrated Waste Management Act was implemented and the California
Integrated Waste Management Board (CIWMB) was formed to oversee these measures.
It requires local governments to divert 50 percent of their waste from
landfills by 2000. Construction and demolition activities generate significant
amounts of waste materials, accounting for 20 to 30 percent of the total
tonnage of California’s municipal waste stream. This waste diversion goal
cannot be attained without support from the building industry.
This information is
intended to provide a general overview of construction site waste management
and waste reduction techniques. More detailed information and guidance is
available from the resources listed at the end of this section.
Creating and carrying
out a waste management plan requires early planning and a commitment to follow
through. ”Waste management” includes many steps, including writing waste
management specifications, determining the economic feasibility of recycling,
and monitoring progress. Some suggestions or considerations are listed below.
The order of these steps may vary.
Each construction
project and job site presents a different set of challenges. Develop a waste
management plan for each project. An effective plan outlines job site waste reduction
goals, identifies targeted materials, describes specific waste reduction
actions to be implemented on a project, and identifies reuse, recycling, or
disposal facilities to
which materials will be taken. This is an extremely important part of the material
management plan.
To address and to
reduce the amount of waste being generated at a construction site, and in turn
to reduce material and disposal costs, a basic understanding of the types and
amounts of material being generated is needed. Since there are so many
different types of structures, varieties of climates in which they are being built, and techniques to construct
them, it would be impossible to quote definitive values for the types and
amounts of waste generated during the construction of a structure. The National
Association of Home Builders (NAHB) has been able to collect data nationally
and compiled estimates on the amounts of wastes generated during construction
on a “typical” 2,000 square foot home. These estimates are based on the
assumption that three sides of the home’s exterior are covered with vinyl
siding and the front facade is brick veneer. Table 1 contains NAHB’s data in
this typical home.
Table 1:
NAHB Construction Waste Estimate
of a Typical 2000 Sq.-Ft House
|
Material |
Weight
(lb) |
Volume (cu. yd) |
|
Solid Dimensional Wood |
1600 |
6 |
|
Engineered Wood |
1400 |
5 |
|
Drywall |
2000 |
6 |
|
Cardboard |
600 |
20 |
|
Metal |
150 |
1 |
|
PVC |
150 |
1 |
|
Masonry |
1000 |
1 |
|
Hazardous Materials |
50 |
- |
|
Other |
1050 |
11 |
Total |
8000 |
50 |
Based on its data, the NAHB
estimated that a typical homebuilder pays $511 per house for construction waste
disposal. The cost will rise as landfill tipping fees increase. Some 80-90
percent of construction waste is recyclable. This indicates that not only could
the disposal costs be significantly reduced through recycling construction
wastes, but also potential income could be realized through the sale of these
materials.
Different materials are generated
at different phases of the project. Use your construction schedule to
coordinate recycling by project phase and by trade. A fast-paced job could
decrease the amount of materials recycled, since many activities will be
happening simultaneously and site recovery efforts may be placed on the back
burner. Careful planning can help minimize this problem. A slow job could
decrease the rate of materials collection below that which is cost-effective.
The problem can be minimized if there is space to store the materials on site.
Select several material types that
are typically recycled, such as wood, cardboard, concrete, and metals. Though
labor costs are often higher for recycling, the lower tipping fees at recycling
facilities can often more than compensate. To determine the cost-effectiveness
of recycling, calculate each material’s cost per ton for recycling versus
landfilling by estimating labor costs, transportation costs, and tipping fees.
Consider working with either your hauler, a professional full-service recycling
contractor, or a waste management consultant to help you identify what types of
materials can be cost-effectively recycled from your project. Each type of
assistance requires different levels of builder involvement.
Most jobs have moderate to severe
space constraints. Develop a plan to “stage” the job site for the most
effective method for storing and collecting both recyclables and waste, and
position recycling bins at the most convenient location for the various trades
to use. Identify “peak generation” times early in the process. Determine what
types of containers are available to collect the materials. Different
containers may be needed at different phases of the project in coordination
with the various trades.
For the program to be successful,
it is important to establish a high level of commitment from the contractor,
subcontractor, cleanup personnel, and waste haulers up front. Some contractors
have waste management training as part of their prebid, preconstruction, and
safety training meetings. Hold your subcontractors accountable for implementing
the waste management plan outlined in the bid package. Provide a package of
information on the recycling program to each new subcontractor when they come
on board.
When dealing with contractors and
subcontractors, who are inexperienced with waste reduction and recycling
practices, expect some errors and inefficiencies because of the learning curve.
Set recycling goals that are realistic for personnel who are learning new
skills. It’s better for morale to exceed the goals than to miss them.
Communicate the success of the program with subcontractors. Encourage everyone’s
ideas and suggestions.
One contaminated box can really
add costs to a successful recycling program. It is helpful to track on a
monthly basis the type, amount and cost of all materials being recycled or
landfilled from the job site. A simple tracking form can be used to develop a
spreadsheet that gives you an up-to-date report that will identify how many
clean dumpsters went off site for reuse and recycling and how many contaminated
and costly dumpsters were taken to the landfill.
Put out press releases on the
success of your project. Clearly identify the job site with signs that tell the
public you are reducing, reusing, and recycling your waste. Let the public know
you are committed to being resource efficient.
In order to minimize the amount of
waste generated at a construction site, planning is necessary on the front end
of the project. When evaluating a structure with the intent of minimizing the
amount of waste generated during the construction process, maximum efforts can
be focused in dimensional planning, use of modular/preconstructed elements, and
other resourceful building techniques.
The first area in which waste
prevention techniques can be incorporated into the construction process is
through dimensional planning. This requires forethought on the part of
designers to ensure a building that creates less construction waste solely on
its dimensions and structural design. Specifically, rooms can be designed of 4
foot multiples, since wallboard and plywood sheets come in 4- and 8-foot
lengths. Furthermore, one dimension of a room can be designed in 6- or 12-foot
multiples to correspond with the length of carpet and linoleum rolls. There
will always be come exceptions that will prohibit a designer from adhering to
standard sizes. At the very least, rooms should be designed whenever possible
with 2-foot incremental dimensions.
Traditional residential
construction still performs the majority of framing and finishing operations on
site in phases. The preconstruction of some elements of the frame, such as
trusses, has become more commonplace in larger developments. As acceptance of
this practice becomes more widespread, along with more manufacturers
preconstructing elements, greater portions of a residential construction
project will occur off-site and be delivered to the job-site for assembly. The
waste generated during the process is eliminated at the job site. When components
are constructed at a factory, less waste is generated because the elements used
are dimensionally equivalent to or close to measurements needed for the
component being assembled. Furthermore, any waste that is generated is more
likely to be recycled because of economies of scale and consolidation of the
scraps.
The elements involved in building
a structure include everything from interior and exterior treatment, trim,
flooring, roofing, coating, utilities, and finishes. With such a vast array of
applications, there are undoubtedly far too many alternatives available for
construction materials and techniques than could be addressed here. Innovative
construction, such as structural foam panels in lieu of wood studs and moveable
interior walls, often surface in model or demonstration homes and are later
incorporated into mainstream construction. Other ideas have been used in larger
scales, such as: increasing spacing the joists and studs to reduce the amount
of framing material required; the use of carpet tiles made from recycled
plastics and decorative tile containing recycled glass; and the use of cutoff
2x wood waste reused for bridging, stakes, bracing, shims, drywall nailers, and
blocking where interior walls run parallel to joists or trusses.
WHERE TO GO FOR MORE INFORMATION
A Technical Manual for Material
Choices in Sustainable Construction. This manual highlights sustainable waste management
principles for planning, design, and construction of large-scale residential
and commercial projects. It provides guidelines, product specifications, and
product data that generally promote sustainable building practices, including
integrated waste management principles. Pub #431-99-009. Calif. Integrated
Waste Mgmt Board (CIWMB), 8800 Cal Center Dr, Sacramento, California, 95826.
(916) 255-2296. www.ciwmb.ca.gov
Construction and Demolition
Recycling Program.
This fact sheet is a four-page summary of CIMWB programs and publications relevant
to construction and demolition recycling. Pub #431-97-030. Calif. Integrated
Waste Mgmt Board (CIWMB), 8800 Cal Center Dr, Sacramento, California, 95826.
(916) 255-2296. www.ciwmb.ca.gov/ConDemo
Residential Construction Waste
Management: A Builder’s Field Guide. This field guide provides builders with information on
cost-effective and voluntary construction waste management. National
Association of Home Builders (NAHB) Research Center, 400 Prince George’s
Blvd, Upper Marlboro, Maryland, 20774. (301) 249-4000. www.nahbrc.com
Fact Sheet Source
The information provided in this
fact sheet was written by the California Integrated Waste Management Board
(CIWMB) and is being used with their permission.