LEED Construction Waste Management: Green Recycling Methods to Reduce Carbon Footprint
Over the last decade, there has been an unprecedented drive towards green and sustainable construction. Today, many public and private influences have integrated green methodologies into typical construction projects, whether driven by local, state, or federal legislation or by private organizations. The universal objective is to develop sustainable and lasting urban projects that expand and preserve, not overexploit, resources. Those who subscribe to the green concept strive to ensure that their projects are highly efficient, built with quality materials, and provide long-term cost savings to future residents, homeowners, and end users. This commitment to a sustainable future ensures that projects make lasting contributions to the neighborhoods and communities in which they are located.
One of the aforementioned private organizations leading the way is USGBC, or the United States Green Building Council. USGBC created a program called LEED to establish guidelines for sustainable development and construction. LEED stands for Leadership in Energy and Environmental Design, and is a rating system for an independent green building certification program that provides voluntary guidelines and third-party verification that a building or community was designed and constructed using strategies intended to improve performance in environmental and human matter. health metrics such as: sustainable site development, water savings, energy efficiency, material selection, and indoor environmental quality. Based on the number of points a particular project achieves in the LEED rating system, a project can earn one of the following certification levels: Certified, Silver, Gold, or Platinum. USGBC says LEED defines “a nationally accepted benchmark for the design, construction and operation of high-performance green buildings” and “provides building owners and operators with the tools they need to have an immediate and measurable impact on the performance of their buildings.” LEED-certified buildings often provide healthier living and working environments, contributing to higher productivity and improving employee health and comfort. The USGBC has compiled a long list of benefits of implementing a LEED strategy, ranging from improving air and water quality to reducing solid waste, benefiting owners, occupants, and society at large.
One of the first and, frankly, easiest strategies that a real estate developer will find and, in turn, achieve would be construction waste management (this appears in credits MRc2.1 and MRc2.2 in the qualification program LEED). The intention of this credit is “divert construction, demolition, and land-clearing debris from disposal in landfills and incinerators. Redirect recovered recyclable resources to the manufacturing process. Redirect reusable materials to appropriate sites.” If a project is trying to achieve this credit in its LEED building certification, the team must “recycle and/or recover at least 50% of non-hazardous construction and demolition debris [or 75% for Credit MRc2.2]. Develop and implement a construction waste management plan that, at a minimum, identifies the materials that will be diverted from disposal and whether the materials will be sorted on-site or commingled. Excavated soil and clearing debris do not contribute to this credit. Calculations can be done by weight or volume, but they must be consistent at all times.” One project that is currently in the process of achieving this credit is the Granada Village Shopping Center in Los Angeles, CA. The project is a remodel of an existing shopping center built in the early 1960’s. Since the scope of work includes the replacement of site works, roofs, storefronts, facades, as well as interior improvements of many buildings; there is a substantial amount of demolition that has to take place. This, in turn, presents a great opportunity to recycle most of this waste that is being disposed of. Since the project team is pursuing LEED Silver building certification, recycling rates are in line with thresholds and are actually well above 75%.
Most projects will require some demolition before construction begins, especially if it involves a remodel of an existing building or a structure needs to be cleared to allow for new construction from the ground up. This creates a perfect opportunity to divert some of the waste that is removed from the building or site for recycling. Some waste will also be generated throughout the construction process. This waste must also be taken into account. The first step is to determine which materials present in the project are recyclable. Materials that recycle well typically include concrete, masonry, metal studs, structural steel, aluminum, wood, cardboard, drywall, acoustical tile, plastic, insulation, glass, and carpet, among others.
The next step is for the project team to develop a plan or protocol on the removal and segregation of the material to be diverted. For tracking purposes, most contractors find it easier to designate a particular area on the site for segregated or mixed collection of recyclable materials. In our experience, unless you are taking your materials to a recycling facility to sort the combined materials for you, it is prudent to literally create separate piles on site for recyclables and landfill waste. To avoid any confusion on the site, some general contractors even put out recycling bins that are clearly labeled with the acceptable (and unacceptable) materials that should be placed in them. We recommend making these labels bilingual and placing them on all sides of the bin, as well as posting wayfinding signs throughout the site that clearly show where these bins can be found. The general contractor must coordinate this plan with all of its subcontractors and suppliers to ensure that recommended handling procedures are followed and that the least amount of waste is produced. These procedures should be written into a Construction Waste Management Plan, distributed, and reviewed at a pre-job meeting with all subcontractors and vendors involved. To truly enforce this plan, it may be beneficial to tell contractors and suppliers that if they do not comply with the plan, they will be subject to late charges and payment withholding. Watch out for crews contaminating dumpsters or dumpsters that have been designated for only one type of material.
That leads to the next step of identifying someone to transport the material off site, as well as the recycling centers that will accept the materials. Whether one is seeking LEED building certification or not, the hauler plays a critical role in managing and documenting the amount of material that is diverted to recycling. When leaving a truckload of debris, the hauler must obtain receipts from the facility accepting the material, which clearly record the quantity, by weight, of each load. The team must also do this with all material that is not recycled, as it is deposited in the local landfill. It is by combining these two types of receipts that the team will be able to determine the total percentage of construction and demolition debris that is recycled.
Another option mentioned above is for the hauler to take the debris to a sorting facility. These facilities do all the hard work for you so you don’t have to separate all the material on site. If the waste is taken to a sorting facility, all the waste can arrive (recyclable and non-recyclable). Different sorting facilities offer different recycling rates. Cities typically publish lists each year of all available sorting/recycling facilities, along with their respective average recycling rates. The redevelopment of the Granada Village shopping center that we discussed earlier currently uses the mixed approach. Since the burden of classification falls on the facility, this allows field work to progress at a much faster rate. There is no need to sort and place each type of material in bins or dumpsters on site. In selecting a recycling facility for this project, the property obviously decided to select a facility that offered a very high recycling rate. However, another factor also had to be taken into account: proximity to the site. Having a facility that was too far from the project would have resulted in higher transportation costs and would have been detrimental to our budget. As any construction estimator can tell you, the export of materials from the site and the transportation/trucking costs can be very expensive. Balancing these two factors led us to select Community Recycling located in Sun Valley, CA, which offers us an average recycling rate of 89.83% for mixed construction and demolition debris and is only 10.5 miles from the site.
When trying to achieve this credit at LEED, there are several other ways to comply besides simply taking the debris to a recycling center. If within the scope of work for the construction of the project, the materials can be recovered on site. Another route to take would be to donate the materials to a charity, such as Habitat for Humanity. Also, instead of taking debris to one facility, why not take it directly to the next source? For example, in Granada Village, a substantial amount of off-site broken concrete materials (approximately 475 tons to date) is shipped directly to Brutoco Engineering & Construction for the Orange Line Extension project just down the road. in Chatsworth, CA. 100% of this concrete material is then crushed, recycled, and reused with the right-of-way for your project. The property was committed to pursuing real estate projects and investments that encourage walking, bicycling, and public transportation, so even having the opportunity to impact another transit project was very exciting for them.
Whether or not a project is seeking LEED building certification, one should always consider a Construction Waste Management Plan and recycle construction and demolition waste if the opportunity arises. Redirecting recovered recycled resources to the manufacturing process and redirecting reusable materials to the appropriate sites helps reduce a project’s carbon footprint and maximize recycling efforts. Reduce, recycle and reuse.