No time to waste: construction-waste management
A construction-waste management plan is now a requirement of many municipalities and sustainable design standards. A thoughtful and well-prepared waste management plan will greatly assist a project in achieving its sustainable goals while reducing the burden on the nation's landfills.
At a time when sustainability is such an important topic in the construction industry, it is imperative to understand how contributions can be made to sustainable goals during demolition and construction by properly planning for demolition and construction waste. Construction, and especially demolition operations, can generate an enormous amount of waste. According to the U.S. Environmental Protection Agency (EPA), 162.2 million tons of construction and demolition debris were generated from buildings in 2013. The American Institute of Architects' best practices indicate that up to 80% of this waste may be diverted from landfills with a thorough construction-waste management plan. As a result, a construction-waste management plan is now a requirement of many municipalities and sustainable design standards.
The first step in creating a construction-waste management plan is setting a quantitative goal. This goal may be set by the owner or authority having jurisdiction, or to comply with a sustainable design standard. An identification plan is then created to determine the types and amounts of the demolition and construction waste. Next is the creation of a waste-reduction work plan for both construction and demolition. The waste-reduction work plan outlines how much of the waste can be disposed of, recycled, and salvaged and establishes the procedures for materials handling and transportation. It should also include a list of local recycling and processing facilities. After this plan is complete, a cost/revenue analysis can be created to compare the total cost of disposal versus the cost incurred by implementing the waste-reduction plan. Onsite training, monitoring, and reporting are all critical parts of the waste management plan, which should be completed by a contractor-designated waste management coordinator.
Construction-waste management should be considered in the early planning stages of a project. By taking it into consideration during design, strategies can be employed by the architect to minimize construction waste. For example:
- Architects can design the construction based on standard sizes of materials, thereby reducing the amount of waste.
- Architects can tailor their design to limit material types and material mixing, thereby reducing the amount of waste from excess materials.
Completing the construction-waste management plan prior to construction, or even at the bidding/negotiation phase, will allow the contractor to also employ several strategies to minimize construction waste. For example:
- Contractors can give priority to suppliers who have a packaging policy, such as those who use minimal packaging, returnable pallets or containers, or recycled or recyclable packaging materials.
- Contractors can develop detailed framing layouts to avoid waste when ordering.
- Contractors can store and cover wood materials on level blocking to minimize waste from rejects due to warping and twisting.
- Contractors can give priority to suppliers who take back excess building materials for recycling or remanufacture.
- Contractors can order gypsum board in optimal dimensions or custom sizes to minimize cutoffs.
A successful waste management plan requires an understanding of the building materials and knowing which materials can be recycled and how. The largest waste material in buildings is portland cement concrete, accounting for 49% of the total waste, followed by wood at 25%. Portland cement concrete can be recycled for use as aggregate fill or riprap. Wood can be recycled in a number of ways: clean, untreated lumber cutoffs can be used for feedstock (raw material) for engineered wood, boiler fuel to produce electricity or steam, landscape mulch, soil conditioner, animal bedding, or as a compost additive. Larger pieces of lumber can be donated to individuals and organizations. Reclaimed wood timbers are also the source for finish materials, such as wood flooring. Several other building materials that can be recycled are as follows:
- Site-clearing waste can be readily recycled by chipping brush, branches, and trees for compost or organic mulch in landscaped areas after being "seasoned."
- Asphaltic concrete paving can be used to make new paving after being reduced in size by grinding.
- Masonry waste, if cleaned up, can often be reused or donated. Broken masonry can be crushed and used as fill or as mineral mulch in landscaped areas.
- Metal is one of the easiest and most commonly recycled construction waste materials. Recyclable metal items include piping, conduit, wiring, banding around bundles, flashing, metal siding, fasteners, and reinforcing bars.
- Gypsum board can, in some cases, be recycled into new gypsum board. Small pieces of gypsum board can be ground up and the shredded paper screened out with the resulting gypsum powder used as a soil amendment. The paper backing can also be recycled once it is removed. Large pieces of gypsum board scraps can be used for small areas of a project or they can be donated.
- Carpet and carpet padding are recycled through carpet manufacturers' reclamation programs. Large amounts of leftover carpet can also be donated. Carpet pads are often recycled by foam recyclers.
- Packaging includes cardboard, boxes, paper, plastic sheets and films, polystyrene packing, crates, and pallets-all of which can be recycled. Crates and pallets can be returned to the manufacturer for reuse, reused on the project site, or broken down and added to the lumber recycling pile.
- Lamps from light fixtures can be recycled including fluorescent, high-intensity discharge, neon, mercury vapor, high-pressure sodium, and metal-halide lamps.
- Insulation that is left over can be installed in interior wall cavities or attics.
- Paints and stains that are unused can be donated or may be accepted by certain retailers or landfills and reused, recycled, or repurposed. Unused portions of latex paint can be made available to consumers without modification or reprocessed into new paint in standard pretinted colors. Some latex paint can be used to make other products or for biodegradation projects at landfills. Oil-based paint can be used in cement plants where it is blended into a fuel and burned to recover the energy value.
- Solvents and sealants that are unused can be donated.
In addition to the many recyclable building materials listed, many types of building components can be salvaged whole from demolition operations if they are properly removed and handled. Items such as railings, cabinets, moldings, trim, doors, hardware, windows, acoustical ceilings, mirrors, appliances, and plumbing and light fixtures can all be reused, donated, or salvaged and resold.
Sustainability has many different facets, and sustainable efforts tend to be largely focused on building design. However, as landfills continue to feel the burden of demolition and construction waste, it is important to shift some of the sustainable focus to limiting construction waste through the design strategies noted above and maximizing demolition and construction-waste material through reuse or recycling. A thoughtful and well-prepared waste management plan will greatly assist a project in achieving its sustainable goals while reducing the burden on the nation's landfills.
-Kristi Duce is an architectural specifications writer for ARCOM. She has an architectural technology diploma from the Southern Alberta Institute of Technology (Calgary, Canada) and more than 15 years of experience in architecture. Kristi is also a registered architect in the state of Arizona. This article originally appeared on ARCOM's blog. ARCOM is a CFE Media content partner.