accelerating waste minimization in residential construction: a source separation case study

This article was downloaded by: [University of Calgary]On: 18 September 2013, At: 09:09Publisher: RoutledgeInforma Ltd Registered in England and Wales Registered Number: 1072954 Registeredoffice: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK

International Journal of ConstructionEducation and ResearchPublication details, including instructions for authors andsubscription information:http://www.tandfonline.com/loi/uice20

Accelerating Waste Minimization inResidential Construction: A SourceSeparation Case StudyRichard A. Boser PH.D., CPC a & Mohamed El-Gafy PH.D., PE ba Illinois State University, Normal, Illinoisb Michigan State University, East Lansing, MichiganPublished online: 25 Feb 2011.

To cite this article: Richard A. Boser PH.D., CPC & Mohamed El-Gafy PH.D., PE (2011) AcceleratingWaste Minimization in Residential Construction: A Source Separation Case Study, International Journalof Construction Education and Research, 7:1, 58-70, DOI: 10.1080/15578771.2011.547063

To link to this article: http://dx.doi.org/10.1080/15578771.2011.547063

PLEASE SCROLL DOWN FOR ARTICLE

Taylor & Francis makes every effort to ensure the accuracy of all the information (the“Content”) contained in the publications on our platform. However, Taylor & Francis,our agents, and our licensors make no representations or warranties whatsoever as tothe accuracy, completeness, or suitability for any purpose of the Content. Any opinionsand views expressed in this publication are the opinions and views of the authors,and are not the views of or endorsed by Taylor & Francis. The accuracy of the Contentshould not be relied upon and should be independently verified with primary sourcesof information. Taylor and Francis shall not be liable for any losses, actions, claims,proceedings, demands, costs, expenses, damages, and other liabilities whatsoever orhowsoever caused arising directly or indirectly in connection with, in relation to or arisingout of the use of the Content.

This article may be used for research, teaching, and private study purposes. Anysubstantial or systematic reproduction, redistribution, reselling, loan, sub-licensing,systematic supply, or distribution in any form to anyone is expressly forbidden. Terms &Conditions of access and use can be found at http://www.tandfonline.com/page/terms-and-conditions

http://www.tandfonline.com/loi/uice20

http://www.tandfonline.com/action/showCitFormats?doi=10.1080/15578771.2011.547063

http://dx.doi.org/10.1080/15578771.2011.547063

http://www.tandfonline.com/page/terms-and-conditions

http://www.tandfonline.com/page/terms-and-conditions

Accelerating Waste Minimization in ResidentialConstruction: A Source Separation Case Study

RICHARD A. BOSER, PH.D., CPC

Illinois State University, Normal, Illinois

MOHAMED EL-GAFY, PH.D., PE

Michigan State University, East Lansing, Michigan

A 2005 study by the California EPA indicated that new residential constructioncomprised about 10% of the C&D waste stream. Most residential construction wasteis typically landfilled and effective waste management remains an elusive goal. Guidedby the ADOP2TTMmodel for diffusion of innovation, this paper presents the results ofa funded project to accelerate the adoption of waste minimization and pollution preven-tion (P2=recycling) practices by Illinois home builders. Key elements of the study werethe identification of priority materials for recycling, local best management practices,and implementation of a demonstration project. The results of the study indicatedthat builders recognize the marketing value of being perceived as a ‘‘green’’ builderand reported their willingness to recycle if the process doesn’t (a) cost more thantraditional landfill fees, (b) increase supervision requirements, or (c) significantlychange work procedures for trade partners. These criteria can most easily be satisfiedby commingling all waste materials and sorting in a recycling facility. In absence ofsuch facilities, onsite source separation of waste during a demonstration project neces-sitated some changes to production and management protocols. Implementation of thewaste management plan required vigilant monitoring of the recycling procedures.

Keywords case study, commingling, residential construction, source separation,waste management plan

Introduction

Construction and demolition (C&D) debris is a large portion of waste disposed inU.S. landfills. Estimates of actual volumes vary widely and range from 20 to 33%of the total landfill waste stream. The U.S. Environmental Protection Agency(EPA) estimated that C&D debris accounts for 24% of all municipal solid waste(Jones, 1993). A more recent California EPA (2004) study reported that C&D wastecomprised 22% of the waste stream. The Construction Materials Recycling Associ-ation (2008) reported that approximately 325 million tons of recoverable C&D mate-rials are generated each year in the United States comprising about one-third of theU.S. waste stream. Although waste estimates are difficult to verify, it is clear thateven at the low end of these estimates there is significant potential for divertingC&D materials from landfills.

Address correspondence to Mohamed El-Gafy, Michigan State University, ConstructionManagement Program, School of Planning, Design and Construction, 114 Human EcologyBuilding, East Lansing, MI 48824. E-mail: [email protected]

International Journal of Construction Education and Research, 7:58–70, 2011Copyright # Taylor & Francis Group, LLCISSN: 1557-8771 print=1550-3984 onlineDOI: 10.1080/15578771.2011.547063

58

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alga

ry]

at 0

9:09

18

Sept

embe

r 20

13

A waste characterization study commissioned by the California EPA (2005)indicated that new residential construction comprised about 10% of the C&D wastestream and that new non-residential (commercial) construction accounted for 8%.Waste recycling from commercial construction is more common than from residen-tial construction because of the higher waste volumes, more space to site recyclingboxes, contracting procedures that require waste separation, and consistent sitesupervision. Recycling in commercial construction is also driven by waste diversionmandates in many jurisdictions such as California and the City of Chicago, and thevoluntary pursuit of Leadership in Energy & Environmental Design (LEED) certifi-cation by owners.

By comparison, single-family residential construction is typically handicapped inrecycling efforts by the very nature of the enterprise where large numbers of inde-pendent builders construct homes on small scattered building sites, generate relativelylow volumes of waste material, and utilize minimal on-site trade supervision. Further,single-family residential construction waste is usually exempt from jurisdictionalrecycling ordinances and mandates.

What is construction waste? Construction activities can generate waste frommany sources such as design error, procurement or shipping error, materials hand-ling, operation error, as well as residual or leftover scraps (Franklin Associates,1998; Gavilan & Bernold, 1994). Similarly, Faniran & Caban (1998) identified typi-cal sources of construction waste as design changes, left over material scraps, wastesfrom packaging and non-reclaimable consumables, design errors, and poor weather,which can damage materials stored on-site. It should be noted that constructionactivities also generate chemical and other special wastes; asbestos most infamously,which is normally regulated strictly for special treatment as they can easily cause pol-lution to the environment or become risks to health. These special wastes were notconsidered in the demonstration project because they are regulated by statutoryframework that requires builders to comply in a predefined way.

Previous studies of waste from single-family home construction in the UnitedStates reported that between two and four tons of debris was generated with eachnew 2,000 square foot home (Jones, 1993; Laquatra & Pierce, 2004; Lund, 1996).As early as 1991, Austin (1991) reported that the majority of home builders wereconcerned about the high cost of construction waste disposal. Average tipping feesacross the country increased from $4.90 per ton in 1976 to $60.00 per ton in 2002.Fees in the Midwest and other regions are relatively low compared to those on Eastand West coast (Chartwell Information, 2008; Yost & Lund, 1995). In early 2010,landfill fees (personal conversation, May 2010) in Central Illinois and the Chicagocollar counties were still in the range of $50 to $60 per ton of waste.

Waste disposal costs impact the affordability of homes as well as a builder’s bot-tom line. The good news for builders was that the robust housing market from 1991through the mid 2000s allowed these costs to be passed along to the home buyer(Laquatra and Pierce, 2004). The National Association of Home Builders (NAHB)has demonstrated that builders pay twice for construction materials that could berecycled but end up in landfills. Payment is made when the materials are purchasedand fees are assessed when the materials are dumped (Yost & Lund, 1995). Thesecosts are then passed on to home buyers in the form of increased home prices. Asidefrom the costs of disposal and affordability, ethical questions related to materialusage and declining availability of landfill space suggest that waste managementbe addressed systematically in all new construction and remodeling.

Accelerating Waste Minimization in Residential Construction 59

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alga

ry]

at 0

9:09

18

Sept

embe

r 20

13

To assist the construction industry, private and governmental organizationshave developed process guidelines and database tools to link waste producerswith firms that recycle or reuse waste materials. The EPA’s Planning Guide for Con-struction and Development (MYER) and NAHB’s Residential Construction WasteManagement (Lund, 1996) identify ways for builders to reduce, recycle or reuse.Internet resources have been developed by many jurisdictions including California’sAlameda County stop waste program (http://www.stopwaste.org) and California’sstate-wide Integrated Waste Management Program (http://www.ciwmb.ca.gov/).The Partnership for Advancing Technology in Housing (PATH) and its informationservice for home builders, Toolbase, provide easily accessible resources related towaste minimization and innovative programs from around the nation, such as aMinnesota project to recycle used asphalt shingles into hot mix asphalt.

Laquatra (2004) noted that in spite of available resources, builders remainreluctant to pursue waste recycling, although up to 80% of construction waste haspotential for diversion from landfills. Toolbase website observed that actual recy-cling is dependent upon the financial cost=benefit tradeoff associated with collection,separation, and transportation of waste materials and the return on investment.Further, existing programs, such as Alameda County’s, are obviously area specificand of little to use to builders beyond an economical transportation distance. Sum-marizing previous research, Bierma & Waterstraat (2001) concluded that decision-makers in small businesses are willing to adopt a new technology or practice if itprovides economic value either by: (a) reducing costs, (b) increasing customer base,or (c) solving headaches, such as simplifying production operations or easing regu-latory compliance. For most builders, diversion of construction waste from landfillshas not yet crossed one of these threshold criteria to yield a business advantage.

Home building requires considerable financial and marketing risks. Therefore,builders’ avoidance of innovation, or at least slow adoption rates, may be rationalbehavior (Koebel et al., 2004; Taylor & Bjornsson, 2002). Diffusion of innovation(DOI) theory is helpful in understanding the barriers to adoption and the meansto overcome those barriers (Rogers, 1995). DOI models such as AcceleratedDiffusion of P2 Technologies (ADOP2TTM) (Lindsey, 1999) accurately predict thatsimply advertising the advantages of pollution prevention in construction are notlikely to lead to widespread adoption. Change agents need to provide opportunitiesfor industry decision-makers to observe successful demonstrations of the innovationat the ‘‘how-to’’ level to reduce risk=uncertainty to a point where adoption canoccur. Figure 1 outlines the basic steps of the ADOP2TTM process. As such, conceptsfrom DOI formed the theoretical grounding for this research.

This paper presents the results of a funded case study and demonstration projectthat involved systematic assessment of P2=recycling practices by selected Illinoishome builders and the development of strategies for accelerating adoption of con-struction waste minimization practices. As recommended by Yin (2009), multiplesources of evidence were utilized to validate research findings including a reviewof literature, interviews with key stakeholders, and observation and data collectionfrom a demonstration project.

Although case studies are often viewed as the most simplistic of research designs,this methodology can provide examples to support and enrich existing research andillustrate important concepts of practice. Speaking to its place in constructionresearch, a recent analysis of over 1100 manuscripts published in the Journal ofConstruction Engineering and Management from 1993 to 2007 found that 16% of

60 R. A. Boser and M. El-Gafy

Dow

nloa

ded

by [

Uni

vers

ity o

f C

alga

ry]

at 0

9:09

18

Sept

embe

r 20

13

these studies utilized a case methodology (Taylor & Jaselskis, 2010). Indeed, Gerring(2004) claimed that much of what we know about the empirical world is drawn fromsingle event or comparative case studies. McKeown (2004) suggested that case stu-dies and observational methods are often highly valuable for clarifying previouslyobscure theoretical relationships. Yin (2009) goes further to recommend that casestudy research is preferred when investigating contemporary events where the beha-viors of interest cannot be manipulated.

Procedures

Citing earlier work by Schramm (1971), Yin (2009) summarized that the ‘‘essence ofa case study . . . is that it tries to illuminate a decision or set of decisions: why theywere taken, how they were implemented, and with what result’’ (p. 17). To thisend, the case study approach is clearly consistent with the goals of this investigation.Although quantitative data were obtained when possible, for example waste volumeand weight, constructs relevant to the diffusion of innovation and acceleration ofP2=recycling practices required a qualitative approach to ascertain (a) the wastematerials that have the greatest potential for P2=recycling, (b) best managementpractices (BMPs) for diverting priority waste, and (c) barriers to the implementationof waste minimization practices by builders. In each of these areas, data acquiredfrom the review of literature, interviews, and observation of practices were analyzedfor consistent themes and trends to understand the conditions that provide incentivesfor waste minimization among residential builders.

Figure 1. Accelerated Diffusion of P2 Technologies (ADOP2TTM) Program Planning Model(Lindsey, 1999).


Dow

nloa

ded

by [

Uni

vers

ity o

f C

alga

ry]

at 0

9:09

18

Sept

embe

r 20

13

The ADOP2TTM Program Planning Model (Lindsey, 1999) provided themethodological framework for this investigation. Following are the major steps ofthe study and a summary of the procedures utilized.

1. Identify and establish a partnership with influential home builders.The influential home builders are typically active with the local chapter of

the National Association of Home Builders (NAHB). The 45 builder membersof the McLean County NAHB chapter were the population for this study. Theresearchers requested and were given time at several NAHB meetings to explainthe purpose of the study and to solicit participation. Partner selection was basedupon the leadership roles in the construction community, perceived readiness toadapt to new practices, willingness to participate in an interview, and potential tohost a demonstration project and act as a mentor for other builders.

2. Identify and quantify typical waste generated by new home construction andidentify which materials have the greatest potential for P2=recycling.

Data was gathered from previous residential waste audits reported in theliterature, interviews with our builder partners who were asked to estimate thepercentage of waste from common building materials, and actual waste haulinginvoice data provided by local haulers for 12 new homes constructed in 2007.

3. Identify local Best Management Practices (BMPs) for diverting the priority wastematerial from the landfill.

Waste diversion is highly dependent upon the local recycling infrastructurehence the first step was to develop a listing of agencies=firms willing to accept pri-ority waste and the costs associated with material reuse=recycling. Data was com-piled through internet searches and interviews with partner builders and wastehaulers. Recycling agencies were contacted by telephone and=or visited to con-firm operations and pricing structures. BMPs related to job-site practices thatbest facilitate waste minimization were derived from the literature and confirmedthrough interviews and site observations at the demonstration project.

4. Survey builder partner to identify barriers to P2=recycling for the priority wastesand identify methods to overcome the barriers.

Interviews were conducted with project partners to identify perceived barriersto the implementation of effective P2=recycling practices and ways to overcomethose barriers. The data collection formats included a combination of paper oremail surveys, face-to-face or telephone interviews, and a focus group held as partof a local home builders’ association meeting. The most useful informationregarding barriers was acquired in working with builders and haulers to establishthe procedures for the demonstration project.

5. Work with builder partners to implement and monitor a waste management planfor a demonstration project.

Builder partners were solicited to participate in a demonstration project. TheMcLean County project was a four-unit townhome of approximately 6,000square feet (1,500 square feet per unit) in Normal, IL. The project began inmid-November 2007 and was finished May 27, 2008 when the last roll-off wastebox was removed from the site. Research team personnel visited the site aboutevery second working day to complete a checklist that documented compliancewith the waste management plan and photograph the site and roll-off boxes tocreate a visual audit trail. Waste volumes and weights were obtained from landfilltickets provided by the hauler.


Dow

nloa

ded

by [

Uni

vers

ity o

f C

alga

ry]

at 0

9:09

18

Sept

embe

r 20

13

6. Facilitate demonstration events whereby other builders can see firsthand how thewaste management plan is implemented.

A demonstration event was held in late March 2008. Details are presented inthe results and discussion section.

Results

Identify and Establish a Partnership with Home Builders

Based on the aforementioned partner selection criteria, 14 home builder members ofthe local NAHB agreed to participate in the study. As the interviews with buildersprogressed, it became apparent that waste haulers needed to be included as researchpartners because of their exclusive service arrangements with specific builders andtheir pivotal role in diverting waste materials to recyclers. Including waste haulersincreased our partner group to 16 participants.

Identify Materials with the Greatest Potential for P2/Recycling

Cornell University, in conjunction with the Home Building Institute (1996), com-piled archival data from waste audits on six residential projects in various locationsin the United States. One project was a 6-unit apartment building; the remaining fivewere single-family homes with an average size of 2350 square feet. To compare andvalidate the waste volumes, a waste audit was conducted by the Cornell researchteam on a bi-level home in Highland Mills, NY. Of the seven projects analyzed,waste volume ranged from 2.5 pounds per square foot (psf) to over 7.0 psf, with bothan average and median of approximately 4.5 psf. By weight, the total waste wascomprised of approximately 40% wood, 29% gypsum board, 5% cardboard, and26% all other materials. The findings reported that percentages of cardboard, wood,and gypsum waste were relatively consistent regardless of the size or style of thestructure. More recent work by Laquatra & Pierce (2004) reported waste volumesconsistent with the 1996 study.

In this current study, Illinois builders were asked during interviews to estimatethe percentage of waste from common building materials. Again the major wastesources of cardboard, wood, and gypsum were within the ranges reported by theCornell study. Subsequent interviews with builders, haulers, and recyclers confirmedthat these three materials comprise the highest percentage of the residential construc-tion waste stream, typically about 75% of total waste, and have the greatest potentialfor recycling.

What was different was the volume of waste. Previous studies suggested averagewaste of 4.5 psf. Landfill records from haulers in this investigation indicated nearlytwice this weight for single-family homes. Indeed, participating builders budgetedfor three 20 cubic yard (CY) roll-off boxes (dumpsters) for the average 2400 SF homewith an expected weight in the range of seven to nine tons, or approximately 5.5 to 7.5psf. Data from the demonstration project, to be detailed later, confirmed these weights.

Identify Local Best Management Practices (BMPs) for Diverting Priority Waste

Best Management Practices for source separation recycling start with the identifi-cation of the local recycling infrastructure for priority waste materials: wood,cardboard, and gypsum. Data gathered from builders and haulers concluded that


Dow

nloa

ded

by [

Uni

vers

ity o

f C

alga

ry]

at 0

9:09

18

Sept

embe

r 20

13

waste diversion is highly dependent upon transportation costs that can rapidly negateany benefit of recycling. In Central Illinois, and many communities of even modestsize, cardboard can typically be recycled and generate a small positive cash flowfor the builder or hauler. Wood recycling facilities are more limited and only one firmprovided this service in Normal, IL, and there were no providers in similarly sizedcommunities within a 50mile radius. Gypsum recycling was even more problematic.While waste gypsum board recycling options exist in surrounding states, there is cur-rently no viable way for Illinois home builders to divert gypsum from the landfill. OnLEED projects, or to comply with mandated C&D recycling in the Chicago area,recyclers will provide a separate weather tight box for storage and eventual recyclingof source separated clean gypsum waste, which is hauled to a facility in Indiana.

Summarized below are the identified BMPs for source separated job siterecycling. The BMPs are focused toward a market solution for recycling specificmaterials where source separation is the only option. That is, a recycling centerfor processing commingled construction waste is not located in the community orwithin reasonable transportation distance. (For an example of the services providedby a recycling center, see http://www.recyclingsystemsinc.com.) This is not to sug-gest that source separation is the preferred method of recycling construction waste,rather it is often the only viable method outside of major metropolitan areas becauseof the lack of other recycling options.

. Identify materials that can be recycled. At a minimum, cardboard, wood, metals,and concrete have high potential for recycling. Before starting construction,review the project construction drawings to inventory the (a) specific types ofmaterials utilized, (b) estimated material waste volumes, and (c) expected con-ditions of materials, i.e., are the materials reusable or only recyclable.

. Locate recyclers that are willing to accept materials at the best price. Researchwhether the materials can be recycled locally. When discussing the types ofmaterials with potential recyclers, inquire as to the (a) required quality of materi-als, (b) handling considerations, (c) volume of materials that the recycler canaccommodate, and (d) cost of recycling services.

. Do your financial homework––is recycling=reuse feasible? Determine the econ-omic benefits of recycling your C&D materials and compare it to the traditionalfees for land-filling or disposal at a transfer station. In jurisdictions that mandatespecific levels of C&D waste diversion from landfills or prohibit specific wastematerials such as concrete or wood from being landfilled, this financial tradeoffanalysis becomes a moot point.

. Develop a waste management plan. Elements of an effective waste managementplan include identification of appropriate recycler(s), waste hauling contractsand considerations, monitoring procedures, planning for on-site storage andsource separation of the construction waste (if possible), or utilization of a recy-cling center. Project storage space and ability to site multiple roll off boxes is thekey factor in the decision to separate on-site or commingle and have separationoccur at a recycling center, if such a center exists in the community.

. Educate your employees and subcontractors. It is important to not only providetraining on expected waste management practices, but to also involve employeesand subcontractors in the establishment of site specific procedures to gain theirsupport, establish a culture that values waste minimization, and therefore toreduce the risk of contaminating recycled materials.


Dow

nloa

ded

by [

Uni

vers

ity o

f C

alga

ry]

at 0

9:09

18

Sept

embe

r 20

13

. Management of waste separation. Until a culture of recycling is established,vigilant oversight will be necessary to assure compliance and avoid contaminationof separated waste. Because of waste handling laws and permitting, even a singlefast food wrapper or scraps of food will technically disqualify a roll-off box ofseparated waste from being recycled. Recycling incentives or penalties specifiedin trade subcontracts may advance waste minimization goals.

Identify Barriers to P2/Recycling and Methods to Overcome the Barriers

Engaging stakeholders through the various data gathering procedures employed inthis study identified numerous barriers to P2=recycling for builders of single-familyhomes attempting to implement an on-site source separation recycling program. Thelessons learned from this process were utilized to develop a draft site-specific wastemanagement plan for builders to evaluate and implement as a demonstrationproject. The waste management plan included the (a) recycling goals, (b) descriptionof P2=recycling procedures, (c) responsibilities of all parties, (d) site monitoringchecklist, (e) supervisor checklist used to gather data monthly from stakeholdersabout the progress and=or barriers of the recycling project, and (f) a waste trackingform similar to Table 1.

Barriers to the implementation of P2=recycling practices are summarized below.In a testament to builders’ knowledge of their craft, these barriers identified priorto the demonstration project proved to be an accurate predictor of what would occurin fact.

. Builders were willing to consider recycling options if the total cost of waste haul-ing did not increase. Although not a barrier from the builders’ perspective, therelatively low cost of landfill fees in the Midwest makes it difficult for market-based recycling to provide economically viable alternatives.

. The average single-family home site does not have adequate space to locate themultiple roll-off boxes needed to facilitate source separation of waste.

Table 1. Project waste material tracking

Load Date Material Hauled

TotalWaste(Tons)

Recycled(Tons)

Volume(CY) Disposal

1 1=25=08 Wood 3.00 3.00 20 CY Recycled2 2=13=08 Trash 3.67 Landfill3 3=7=08 Trash� 1.85 Landfill4 3=7=08 Trash 2.99 Landfill5 3=11=08 Wood 3.00 3.00 20 CY Recycled6 3=29=08 Trash (mostly gypsum) 3.49 Landfill7 3=31=08 Trash (mostly gypsum) 2.64 Landfill8 4=4=08 Trash (mostly gypsum) 1.43 Landfill9 5=8=08 Cardboard 0.62 0.62 Recycled

10 5=27=08 Trash 1.75 LandfillTotal 24.44 6.62 27% Diverted

�Load #3 was source separated cardboard contaminated when almost 100% full.


Dow

nloa

ded

by [

Uni

vers

ity o

f C

alga

ry]

at 0

9:09

18

Sept

embe

r 20

13

. While legally and technically possible, recycling gypsum board in Illinois appearsto be effectively blocked administratively by the Illinois Environmental ProtectionAgency.

. Builders work with specific haulers, not all of whom were willing to change prac-tices or disposal routes to accommodate recycling.

. Illegal dumping of non-construction refuse, such as garage sale remnants, furni-ture, and toxic materials, can quickly undermine builder enthusiasm for recycling.Most jurisdictions now require roll-off boxes to be tarped at the end of the workday. Some builders report that tarping does discourage illegal dumping; othersreport that the non-construction materials are simply placed on top of the tarp.The solution to illegal dumping in commercial construction is gated and lockedproject sites; however this is not feasible on scattered single-family housing sites.

. Source separation requires significant supervision, trade education, and on-goingmonitoring, all of which increase time demands on site supervisors and couldpotentially increase overhead costs.

Solutions to these barriers are difficult to affect when waste must be sorted andseparated on-site. Some options were explored. For space considerations, one haulerproposed partitioning a roll-off box to handle more than one type of sorted materialper load. Partitioned roll-off boxes are already utilized by the municipality to collectand recycle paper, cardboard, and containers. Unfortunately, the innovative haulerdid not have contracts with any of our builder partners who wished to remain loyalto their current waste haulers. As mentioned above, tarping roll-off boxes does detersome illegal dumping, but certainly not all. However, almost all of these barriersdisappear if construction waste can be commingled in one roll-off box on site andseparated at a recycling center. In this context the builder does not need to changework practices, haulers only go to one tip facility, and although illegal dumpingmay add some additional cost because of increased waste volume it would notcontaminate sorted materials. At the time this study was conducted, facilities thatrecycle commingled construction waste were not available in Illinois outside of theChicago metro area.

Implementation of a P2/Recycling Plan and Demonstration Project

Builder partners were solicited to host a demonstration project at a single-familyhome site. However two of the previously mentioned barriers worked to negatethe single-family home option: (a) limited space for locating roll-off boxes, and(b) builder’s loyalty for working with specific haulers who were not willing to alterpractices to facilitate recycling. Moreover, the economy, led by the collapsing hous-ing market in late 2007, was already in obvious decline at the time the researcherswere attempting to persuade builders to undertake a demonstration project. Eventu-ally a builder partner agreed to host a demonstration project on a four-unit town-home of approximately 6,000 square feet (1,500 square feet per unit) situatedalong a major thoroughfare in a new subdivision. In this case there was adequatespace for multiple roll-off boxes and the waste hauler was cooperative. The projectbegan in mid-November 2007 and was finished at the end of May 2008 when the lastroll-off box was removed from the site.

Prior to framing stage, there were no roll-off boxes on-site, as the foundation andsite contractors recycled all concrete overage and removed their own waste materials,


Dow

nloa

ded

by [

Uni

vers

ity o

f C

alga

ry]

at 0

9:09

18

Sept

embe

r 20

13

which were minimal. At the framing stage, two 20 cubic yard (CY) roll-off boxes wereplaced on site: one for wood and one for residual waste=trash. In February 2008,coinciding with the installation of vinyl siding that was delivered to the site in card-board cartons, a 20 CY roll-off box for ‘‘cardboard only’’ was also placed on-site.Roll-off box signage was ordered from WasteCap Wisconsin in late December2007 with signs positioned as boxes were placed on-site. At a maximum, there werethree roll-off boxes for source separation, one each for wood, cardboard, and trash.

A professionally prepared project sign was erected to increase public awarenessand to enhance trade and delivery compliance with the waste management plan.Other measures to communicate and promote the project recycling requirementsincluded (a) recycling compliance on the agenda for all project meetings, (b) signageon the entry door to each unit, and (c) signage on all four sides of the roll-off boxes.In addition, a well publicized open house and demonstration event was hosted oncethe building was weather tight. Unfortunately the event drew more media represen-tatives than builders.

The project generated 24.44 tons of waste that was hauled off the site in tenloads. The waste equaled 8.15 pounds per square foot. Two 20 CY boxes of woodand one 20 CY box of cardboard were recycled. Recycled material weighed 6.62 tonsand resulted in 27% of the waste being diverted from the landfill. Regrettably,another almost full 20 CY box of cardboard was contaminated when a skid loadercleaning the project parking lot dumped mud and other refuse into the box. Failureto recycle this load of cardboard decreased the diverted waste by approximately1,200 lbs. Table 1 provides waste tracking data for the demonstration project.

Three roll-off boxes of mostly gypsum board waste weighed 7.56 tons or 30% ofthe total project waste by weight. Estimating the gypsum waste ratio at 80% of thetotal weight of each load yielded approximately 12,000 pounds or 2 pounds persquare foot. This amount is double the rule of thumb value of one pound per squarefoot of floor area for single-family residential construction suggested by previousstudies. The significant increase in gypsum board waste may be attributed to severalfactors at play in comparatively small multi-family units. First, relatively small roomsizes generate a higher percentage of waste from window and door cutouts per floorarea than larger units. Second, double layers of 5=8 inch Type X gypsum board and=or 1 inch gypsum shaft wall were utilized for the fire rated wall assemblies betweenthe four units. These additional fire rated walls running from the foundation upthrough the gable roof attic space, not required in detached single-family homeconstruction; add significantly to both the quantity of gypsum materials requiredand the potential for waste volume from off-cuts. No comparable data were locatedfor gypsum board waste in multi-family housing versus detached single-familyhomes.

Overall, waste recycling and source separation procedures were executed as perthe waste management plan. Most subcontractors were cooperative and responsive.The percentage of waste diverted was lower than planned, 27% vs. a project goal of40%. Wood comprised most of the diverted waste weight: 40 CY with an approxi-mate weight of 6 tons. Using previous research from single-family homes asguidance, wood should have contributed approximately 40% of the total waste versesthe 24.5% documented. The lower volume of wood waste on this project was a posi-tive feature attributed to prefabricated panelized wall frame sections and roof trussesthat minimizes the wood needed for structural components as well as reducingoff-cuts.


Dow

nloa

ded

by [

Uni

vers

ity o

f C

alga

ry]

at 0

9:09

18

Sept

embe

r 20

13

Discussion

The builders in this study recognized the marketing value of being perceived as‘‘green’’ and reported their willingness to recycle if the process doesn’t cost morethan traditional landfill fees or significantly change work procedures for trade part-ners. The findings indicated that waste management costs can remain comparablewith the costs of direct disposal at a landfill. Indeed, the demonstration projectneeded one less roll-off box over the course of the project than estimated. However,source separation did require procedural changes for builder supervisors, tradepartners, delivery personnel, and haulers; and in spite of overall compliance withthe source separation procedures, contamination of separate waste material was aconstant concern.

For example, the gypsum supplier put dunnage in the well marked ‘‘cardboardonly’’ box on two occasions. This lack of compliance did not appear malicious;rather delivery personnel and trade contractors were just not used to working onresidential projects with recycling requirements and even the signage needed to beexplicitly pointed out to the truck driver. As opposed to commingling waste onthe construction site and sorting in a facility off site, source separation clearly placesthe burden of sorting for recycling on construction personnel and vendors.

Given that such facilities are typically located only in major metropolitan areasand not within an economical transportation distance for most builders, sourceseparation will continue to be a necessary approach if construction waste is to bediverted from landfills. In spite of the difficulties associated with source separationon the demonstration site, the builder’s project manager indicated that they wouldconsider utilizing recycling and waste minimization practices on future multi-familyprojects.

Summary and Conclusions

This paper presented the results of a funded project to accelerate the adoption ofwaste minimization and pollution prevention (P2=recycling) practices by Illinoishome builders. Key elements of the study included the identification of prioritymaterials for recycling, local best management practices, and facilitation of a dem-onstration project. Based upon the data gathered, a waste management plan wasdeveloped and a builder and waste hauler solicited to participate in a demonstrationproject. A multi-family site was selected, a four-unit townhome, because it providedadequate space to site the multiple roll-off boxes required to facilitate on-site sourceseparation of waste. The following conclusions were derived from the results of thestudy.

Documented waste volumes were almost double the average reported in earlierstudies: 8.15 psf vs. 4.5 psf. This waste volume was consistent with the expectationsof building partners who budgeted three 20-cubic-yard (CY) roll-off boxes for anaverage 2400 SF home with an expected disposal weight in the range of seven to ninetons, or approximately 6.0 to 7.5 psf. Supplemental data requested from local wastehaulers reported similar disposal volumes and weights from a sample of 12 newsingle-family homes constructed during the previous year.

In Central Illinois, cardboard has the most mature recycling infrastructure andpaid a small premium to the hauler. The premium was retained by the hauler ascompensation for altering their regular disposal routes. Wood could be recyclable


Dow

nloa

ded

by [

Uni

vers

ity o

f C

alga

ry]

at 0

9:09

18

Sept

embe

r 20

13

in the community where the demonstration project was located, but not in otherCentral Illinois cities of similar size. The cost for recycling wood was similar to land-fill tipping cost and was therefore budget neutral.

Recycling scrap gypsum board was not possible in spite of the researcher’sefforts to facilitate options to use the material as a composting additive, soil amend-ment, or animal bedding. It was difficult to enthuse builders and haulers aboutdiverting construction waste when there were no alternatives for recycling wastegypsum board, which typically comprises about 25% of the total waste by weight.The state Environmental Protection Agency, through the permitting process, is thegypsum recycling gatekeeper. Accelerating P2=recycling is at least partially depen-dent upon finding ways to recycle waste gypsum products that are acceptable toall stakeholders.

Source separation required procedural changes for builder supervisors, tradepartners, delivery personnel, and haulers. Trade partners needed to sort wasteinto the appropriate roll-off boxes adding time to their typical routines. The sitesuperintendent had to promote the recycling program and educate the trade part-ners. Haulers were obliged to adjust disposal routes to accommodate trips to variousrecycling service providers, and locate recycling boxes for wood and cardboard onsite for longer periods of time. These changes in practices impacted productivityfor all stakeholders and were a source of resistance to the P2=recycling effort. Asa result, implementation of the waste management plan required vigilant monitoringof the recycling procedures to assure compliance and avoid contamination of sepa-rated waste. According to waste handling laws and permitting requirements, even asingle fast food wrapper or scraps of food will technically disqualify a roll-off box ofseparated waste from being recycled. In spite of these difficulties, contractualremedies such as specific contract language or withholding payments for non-compliance, often used in LEED projects to further recycling goals, were not favoredby residential builders.

The numerous barriers to source separation of residential construction waste aredifficult to overcome. The size of single-family home sites is not conducive to themultiple boxes needed for waste separation. Production and supervision practicesneed to be altered. Illegal dumping can be demotivating for all stakeholders. Thesebarriers largely disappear if construction waste can be commingled in one roll-offbox on-site and separated at a recycling center. Commingled waste essentially meansno change in job site practices. Unfortunately, the economics of recycling centersgenerally relegate these facilities to large metro areas.

While much was learned about the recycling behavior of builders, trade contrac-tors, and waste haulers, accelerating P2=recycling remains an elusive goal if the onlyavailable method is source separation of waste. Builders are rational entrepreneurswho will adopt new means and methods when they are convinced the benefitsoutweigh the financial risks, or if compliance is mandated. To date, neither of thesefactors are part of the home builder calculus in Central Illinois. Accelerated changemay have to await changes in the business or regulatory environment.

Acknowledgments

Funding was provided by the Illinois Sustainable Technology Center of the IllinoisDepartment of Natural Resources (Contract No. HWR007209). We are gratefulto Ken Barnes, Nancy Holm and to staff members at the Illinois Sustainable


Dow

nloa

ded

by [

Uni

vers

ity o

f C

alga

ry]

at 0

9:09

18

Sept

embe

r 20

13

Technology Center for helpful comments and advice. The research and opinionsexpressed here are those of the writers and do not reflect those of the Illinois Sustain-able Technology Center.

References

Austin, T. (1991). Building Green, Civil Engineering, August, 52–54.Bierma, T. & Waterstraat, F. (2001). Chemical management: Overcoming barriers to diffusion.

Champaign, IL: Illinois Waste Management and Research Center.California EPA. (2004, May 7). Statewide waste characterization study. http://www.ciwmb.

ca.gov/Publications/LocalAsst/Extracts/34004005/ExecSummary.pdfCalifornia EPA. (2005, May 7). Targeted statewide waste characterization study: Detailed

characterization of construction and demolition waste. http://www.ciwmb.ca.gov/Publications/LocalAsst/Extracts/34106007/ExecSummary.pdf

Chartwell Information (2008, September 12). Solid waste market: Data and research. Environ-mental Business International, Inc. http://www.wasteinfo.com/data.htm

Construction Materials Recycling Association. (2008, August 28). http://www.cdrecycling.org/Faniran, O. & Caban, G. (1998). Minimizing waste on construction project sites. Engineering,

Construction and Architectural Management, 5(2), 182–188.Franklin Associates (1998). Characterization of building-related construction and demolition

debris in the 36 United States. Washington, DC: U.S. Environmental Protection Agency.Gavilan, R. M. & Bernold, L. E. (1994). Source evaluation of solid waste in building

construction. Journal of Construction Engineering and Management, 120(3), 536–555.Gerring, J. (2004). What is a case study and what is it good for?’’ American Political Science

Review, 98(2), 341–354.Jones, D. A. (1993). Dodging the dump, Builder, May, 246–249.Koebel, C., Papdakis, M., Hudson E., & Cavell M. (2004). The diffusion of innovation in the

residential building industry. Report for the Office of Policy Development and Research.Washington, DC: U.S. Department of Housing and Urban Development.

Laquatra, J. & Pierce, M. (2004). Waste management at the residential construction site.Journal of Solid Waste Technology and Management, 30(2), 67–74.

Lindsey, T. C. (1999). Accelerated Diffusion of Pollution Prevention Technologies(ADOP2TTM). Pollution Prevention Review, 9(2), 33–37.

Lund, E. (1996). Residential construction waste management: A builder’s field guide. UpperMarlboro, MD: National Association of Home Builders Research Center.

McKeown, T. (2004). Case studies and the limits of the quantitative worldview. In Bradey, H. andCollier, D. (Eds.) Rethinking social inquiry: Diverse tools, shared standards (pp. 139–153).Lanham, MD: Rowman and Littlefield.

Rogers, E. M. (1995). The Diffusion of innovations, 4th ed. New York, NY: Free Press.Schramm, W. (1971). Notes on case studies. Washington, DC: COSMOS Corporation.Taylor, J. & Bjornsson, H. (2002). Identification and Classification of Value-drivers for a New

Homebuilding Supply Chain, Proceedings of the Tenth Annual Conference of the Inter-national Group for Lean Construction IGLC-10, pp. 1–12. Gramado, Brazil.

Taylor, J. E. & Jaselskis, E. J. (2010). Introduction to the special issue on research methodol-ogies in construction engineering and management. Journal of Construction Engineeringand Management, 136(1), 1–2.

Yin, R.K. (2009).Case study research: Design and methods, (4th ed.). ThousandOaks, CA: Sage.Yost, P. & Lund, E. (1995). Residential construction waste management demonstration and

evaluation. Prepared for U.S. Environmental Protection Agency, Office of Solid Waste.Upper Marlboro, MD: National Association of Home Builders Research Center.


Dow

nloa

ded

by [

Uni

vers

ity o

f C

alga

ry]

at 0

9:09

18

Sept

embe

r 20

13

accelerating waste minimization in residential construction: a source separation case study

Documents