This handbook exists as the result of a desire by the Houston- Galveston Area Council (H-GAC) to provide assistance to the area's residents for the purpose of addressing the Construction and Demolition (C&D) waste issues of the area. The Houston Advanced Research Center (HARC) was contracted to do the research and to produce the handbook. It is with great humility that we share this educational tool for the residents of the thirteen counties that comprise the service area for H-GAC.
What this Handbook Contains
Below is a list of the chapters of this handbook:
A more detailed outline can be found in the Table of Contents. Commonly used terms and acronyms can be found in the Glossary.
- Where to Start?
- Design Opportunities
- Evaluating Waste and Identifying Opportunities
- Disposal Regulations
- Additional Information Resources
- Recycling Vendors
Background – The National Picture
Construction and demolition (C&D) waste generally refers to any waste from land clearing, construction, renovation, and demolition projects. C&D waste includes building materials, packaging, and land clearing debris.
Building related C&D waste represents 10 – 30% of the nation's total waste stream to landfills. A 1998 study by the United States Environmental Protection Agency (EPA) details many observations about C&D waste:
Specifics for the Houston-Galveston Region
- In 1996, 136 million tons of building-related C&D waste was generated
- That's 2.8 pounds per person per day!
- 57% non-residential; 43% residential
- 8% new construction, 44% renovation, and 48% demolition
- In 1996, 20 – 30% of C&D waste was recovered for reuse or recycling
- 3,500 facilities processed this C&D waste for recovery
Texas is a big place, but many resources are not infinite, including landfill capacity. In fact, the Texas Commission on Environmental Quality (TCEQ), in a 2002 study, estimated that the 13 counties in the Houston-Galveston Area Council would run out of landfill capacity in the year 2016. A newer study June 2005 estimates the date at 2036 if every planned landfill expansion is executed.
The Houston-Galveston region is growing rapidly. We are constructing more than 36,000 new single family homes each year. And we are remodeling many times more of these single family homes. Our businesses and industries continue to grow at better than national rates contributing even more construction and demolition waste into the waste stream. There is absolutely no doubt that the cumulative effect of the residential and commercial remodeling, demolition, and construction projects represent an enormous amount of C&D waste. Clearly both the residential and commercial construction industry can help extend the life of the region's landfills through better C&D waste practices.
The Residential Fraction
Just under half (43%) of all C&D waste is from residential sites. The EPA studied 15 single-family home construction sites, and found an average waste generation of 6.14 pounds per square foot. However, the range was broad: 2.41 to 11.30 pounds per square foot – house size is not the only determining factor of waste production. Location and construction materials widely employed in a region have a huge impact on the amount of waste.
The National Association of Home Builders Research Center estimated that 8,000 pounds of waste is thrown into the landfill for a typical 2,000 square foot home. The table below shows the amount of waste by type:
(in cubic yards)
|Solid Sawn Wood||1,600||6|
Calculating Your Waste Stream
Understanding the waste stream that your projects generate is the first step in minimizing waste and saving money. One complication of understanding the waste stream is using consistent units. Since drywall is far denser than cardboard, a dumpster full of drywall will weigh far more than a dumpster of cardboard. The following table presents useful conversion factors, adapted from the National Association of Homebuilders study.
per Cubic Yard
|Solid Sawn Wood||267||0.004|
|Paints, Caulks, etc.||167||0.006|
Options for Building, Remodeling, and Deconstructing Projects
Builders, remodelers, and deconstructers can all save money and help conserve landfill space by practicing the 3Rs: Reduce, Reuse, Recycle.
Reducing waste can be both the simplest, and the most beneficial of the 3R's. Not only can reducing waste save money once, by saving disposal fees, but can save money twice, by reducing the need to purchase materials. Planning ahead, with waste reduction in mind, is key to a successful waste reduction effort. The Peaks to Prairies Pollution Prevention Information Center describes three strategies for reducing construction and remodeling waste:
- Design out waste
- Know what you typically throw out and focus on finding alternatives
- 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 re-used and salvaged building materials into the building's design
- Cut and fill on-site; don't haul top soil off site
Prevent on-site waste
- 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
Reuse and Recycle
- Establish inventory and housekeeping procedures; train employees to follow the procedures
- 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 re-used; have supplier come and pick them up after use
In the case of construction waste, there is great overlap between reuse and recycle. All of the methods described here are basically methods for reuse: waste materials are either reused as-is, or they are pulverized and reused. The basic challenge of reuse and recycling is not that scrap materials have no value (in fact, they are quite valuable), but that they lose their value if they become mixed together or commingled. Thus the key to successful reuse programs is waste separation, and that means planning ahead for separation and conveying this information to everyone working on the site.
Some valuable waste materials are:
Methods to Reuse and Recycle
- Lumber Cutoffs
- Drywall Cutoffs
- Hardware and Fixtures
- Metals and Wiring
- Brick and Masonry
There are two general places to reuse and recycle construction materials: on the jobsite and off the jobsite. Again, the key to a successful program is planning ahead, communicating the plan to all the workers and subcontractors, and ultimately a working system of separating waste materials.
Generally, there are three methods for materials separation: onsite separation in containers, onsite separation in piles, and offsite separation. Unlike other regions where industries exist to separate commingled waste and salvage or recycle valuable components, there is no such industry in the Houston region, so offsite separation is not a viable option here. On-site separation into containers is best for materials generated in large volumes that will be hauled offsite for recycling. As always, containers should be out of view of the road, to avoid others dumping materials into the containers and contaminating them. On-site separation into piles is best for materials that will be reused onsite.
On-site Reuse – Whole
On-site reuse is very efficient: the material is used on the site, requiring no extra equipment, and little extra effort. Large lumber cutoffs should be used when a small piece of lumber is needed, e.g. for bracing. Drywall scraps can be used as fillers in closets.
Separate the waste stream (e.g. have a lumber pile, a drywall pile, etc). Use the cut-offs whenever possible. Consider using a small trash can to collect cut-offs where they are being created and reused – this keeps the site neat, and makes it easy to reuse.
On-site Reuse – Pulverized or Grinding
On-site reuse of pulverized materials (sometimes called onsite recycling) is an efficient means of using waste that would otherwise be sent to the landfill. Lumber, drywall, brick, mortar, hardiplank, shingles, and other materials can be pulverized in a portable grinder, (http://www.packer2000.com/) and reused as mulch, soil amendments, or fill – avoiding expensive purchases of these materials. For example, chipped wood can be used to create a mud-controlling pad on the site, which helps keep the site clean (which impresses owners, specifiers, and prospective buyers) and avoids the slower rate of progress that often follows heavy rains. And, of course, the chipped wood is free - saving the hundreds of dollars per dump truck load that builders often pay for crushed concrete to serve the same purpose.
Separate the waste stream (e.g. have a lumber pile, a drywall pile, etc). After all waste of a certain type has been produced, grind and reuse it.
If there are extra materials onsite, these should be salvaged and used offsite when possible. Items such as bricks, hardware, fixtures, and shingles can be taken offsite for use, or they can be sold or donated to another organization. Habitat for Humanity operates a "ReStore" building supply outlet, which accepts donated materials, and re-sells them, the proceeds benefit Habitat for Humanity. See the attached directory for information on the ReStore and other facilities that accept unused building materials.
Offsite Recycling and Selling Scrap Materials
The Houston region does have a market for recyclable materials. Copper wiring generally sells for about $1.08 per pound, so a smart electrician will keep all but the smallest of scraps. Most metal scraps can also be sold profitably. Although recyclers might not actually pay you for containers of recyclable wood or cardboard, they generally charge a much lower tipping-fee than a landfill, allowing you to save close to 50% on disposal costs for loads of separated wood or cardboard.
Although the strategies above are presented separately, it is crucial to remember that they can easily be combined – and to maximize profits by using, reusing, and reselling materials most efficiently, you should combine several of them. The key to all of these strategies, and to combining them, is planning and separation of materials.
Haul offsite for recycling (at reduced tipping fees) any un-pulverized wood or cardboard, and haul remaining waste (if other steps have gone well, there will not be much left!)
- Design out waste;
- Consider what wastes will be generated onsite;
- Consider when they will be generated;
- Plan to separate materials;
- Keep materials that will be directly reused convenient for reuse;
- Use small trash cans to keep reusable scraps handy;
- Add unused scraps to piles/containers for grinding/removal;
- Salvage for reuse or sale;
- Metals and wiring;
- Pulverize and reuse onsite;
- Wood (untreated);