Another aspect to consider in constructing with pollution prevention (P2) in mind is solid and hazardous wastes. Considering waste during the planning and design processes can achieve the most efficient use of materials. Sorting waste produced on-site can further reduce what goes to the landfill.

• In the U.S., the total annual construction and demolition waste generated accounts for 136 million tons of landfill materials. Approximately, 43% (58 million tons) of this total is from residential construction, demolition and renovation projects. Source: http://peakstoprairies.org/ConstructionWaste/
• It is estimated that 8,000 lbs. of waste is thrown into the landfill during construction of a typical 2,000 square foot home. The makeup of this waste is estimated in the following table.
  

"Typical" Construction Waste Estimated for a 2,000-Square-Foot Home

Although construction wastes vary from one site to another other studies reflect similar trends in characteristics of waste materials with wood, drywall and cardboard contributing the largest percentages of material. Materials in the "other" category may include glass, ceramic, aggregate, rubble, paper and paperboard, plastic, electrical wire, carpet, rubber, insulation, and miscellaneous items and scraps.

Regulations for handling, transport and disposal of solid and hazardous waste vary from state to state and sometimes community to community.

• Contact local environmental regulatory agency for guidance.
• Avoid waste disposal through prevention practices.
• If a potentially hazardous material spills, contact proper authorities immediately.

Typically, waste from new construction sites is cleaner than that from demolition or renovation sites. Demolition and renovation may produce additional special wastes, e.g. asbestos, lead, fluorescent lamps and ballast, etc. which must be handled according to local regulatory guidelines. New construction waste is generally considered non-hazardous although hazardous components can exist within the debris. (Refer to the Hazardous Waste link in above table for more information about hazardous and special wastes). A waste audit is required to characterize waste produced at specific construction sites and to determine the hazardous component. Material Safety Data Sheets (MSDS) provided by product manufacturers can provide some information to help make this determination. Procedures for purchasing, inventory and use can then be developed appropriately to ensure safety and to assist with the reduction of waste materials.

There are many reasons to focus on solid and hazardous waste management as one aspect of an integrated approach to green building. Many of the benefits of resource-efficient construction are recognized through proper solid and hazardous waste management.

2. Liability, Health and Safety

Residential construction waste has the potential to adversely impact health, safety, water and air quality. Solid and hazardous waste storage and handling can contribute to trips and falls, unintended exposure to harmful substances, releases, spills and unauthorized or illegal disposal. Less waste on-site means a cleaner, safer site and less potential liability resulting from 'accidents'.

3. Market Appeal and Community Relations

Efforts to proactively manage construction waste are worth talking about. The public will appreciate contractors who: value the environment by saving natural resources and valuable landfill space; value their employees safety by keeping clean and safe sites; and value their communities by putting less stress on already overburdened services (roads and landfills). Housing prices will reflect the value of the homes' contents and the workers' skills, not what had to be cleaned up. Municipalities, clients and neighbors will respond positively.

What can a builder do to minimize the waste produced during construction? Waste management begins with prevention, ie. eliminating waste streams before their creation. Reduction of waste will reduce costs associated with handling, managing and disposing of these materials, it may even reduce material costs by enhancing efficiency of the materials purchased. Both solid and hazardous waste can be reduced through the following steps:

1. Design out waste

• Base design dimensions on standard material sizes
• Determine process modifications that reduce waste and specify them
• Favor designs that use materials efficiently e.g. two-foot module, stacked framing and single top plate (Optimum Value Engineering)
• Incorporate reused and salvaged building materials into the building's design
• Know what you typically throw out and focus on finding alternatives
• Cut and fill on-site; don't haul top soil off site

2. Purchase "Green"

• Choose engineered products that reduce rejects
• Incorporate reclaimed materials into the project
• Make accurate supply estimates and order only what is needed; do not overstock inventory (especially chemicals which can expire)
• Choose products with minimal or no packaging; work with suppliers to reduce packaging
• Use materials that do the job with the least toxicity
• Purchase green materials, equipment and appliances throughout the project

3. Prevent on-site waste

• Establish inventory and housekeeping procedures; train employees to follow the procedures
• Train employees to use equipment properly
• Properly label containers to avoid mixing incompatible materials
• Ask suppliers to take or buy back any substandard, rejected, or unused items
• Request supplies be delivered on sturdy pallets or containers that can be reused; have supplier come and pick them up after use

Materials that cannot be eliminated through design, procurement decisions, and take-back programs can be further eliminated from the waste stream by reuse or recycling. Check with your state and/or local environmental regulatory agencies regarding specific handling procedures and requirements regarding hazardous wastes. The following are steps to follow when managing waste streams:

1. Plan for management

• Conduct an audit of waste produced
• Involve everyone from distributors to subcontractors to recycling facilities; familiarize yourself with opportunities, and them with on-site procedures
• Write clear procedures, e.g. separate materials into appropriate bins or stacks; remove contamination, such as plastic or nails; day and time for pickup, etc.
• Train employees to follow procedures
  

2. Reuse / Salvage

• Reuse waste on-site first, e.g. wood scraps for bracing, drywall scraps as fillers in closets, etc.
• Work with local salvage centers and used material exchanges for lumber, fixtures, appliances, masonry, roofing, etc.
• Donate larger pieces of scraps or other usable materials to local housing programs, e.g. Habitat for Humanity
  

3. Recycle

• Recycle waste on-site first, e.g. grind gypsum board as a soil amendment
• Work with local recycling centers to haul cardboard, wood, gypsum board, plastic, etc.
• Buy recycled products to support the markets for off-site recycling efforts

4. Follow-up

• Review sorting, stacking, and handling procedures with crew and on-site procedures with salvage and recycling haulers; provide them with written copies of procedures
• Spot check to ensure that all subcontractors and haulers understand and follow the procedures

Approximately 70% of construction waste consists of metals, wood, drywall, and cardboard. All of these materials can typically be reused or recycled on- or off-site. Lists of waste handlers and recyclers in your area can be obtained from your state or local environmental agencies.