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Pavement Marking Warranty Specifications (2010)

Chapter: Chapter Four - Conclusions

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Suggested Citation:"Chapter Four - Conclusions." National Academies of Sciences, Engineering, and Medicine. 2010. Pavement Marking Warranty Specifications. Washington, DC: The National Academies Press. doi: 10.17226/14437.
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Suggested Citation:"Chapter Four - Conclusions." National Academies of Sciences, Engineering, and Medicine. 2010. Pavement Marking Warranty Specifications. Washington, DC: The National Academies Press. doi: 10.17226/14437.
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Suggested Citation:"Chapter Four - Conclusions." National Academies of Sciences, Engineering, and Medicine. 2010. Pavement Marking Warranty Specifications. Washington, DC: The National Academies Press. doi: 10.17226/14437.
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Page 42
Suggested Citation:"Chapter Four - Conclusions." National Academies of Sciences, Engineering, and Medicine. 2010. Pavement Marking Warranty Specifications. Washington, DC: The National Academies Press. doi: 10.17226/14437.
×
Page 42
Page 43
Suggested Citation:"Chapter Four - Conclusions." National Academies of Sciences, Engineering, and Medicine. 2010. Pavement Marking Warranty Specifications. Washington, DC: The National Academies Press. doi: 10.17226/14437.
×
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Suggested Citation:"Chapter Four - Conclusions." National Academies of Sciences, Engineering, and Medicine. 2010. Pavement Marking Warranty Specifications. Washington, DC: The National Academies Press. doi: 10.17226/14437.
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39 OVERVIEW OF FINDINGS This synthesis study has compiled information on pavement marking warranty specifications used by U.S. state depart- ments of transportation (DOTs) and Canadian provincial/ territorial road agencies, with further comparisons to European practice. Pavement markings play an important role in reduc- ing congestion and improving safety by providing informa- tion, guidance, and warnings to road users, whether drivers of motorized vehicles, bicyclists, or pedestrians. Transportation agencies typically consider using pavement marking war- ranties to gain one or more benefits; for example, superior pavement marking performance, reduced need for inspection personnel, greater cost-effectiveness, reduced risk of prema- ture failure, and potential for contractor innovation. Information on pavement marking warranties has been obtained through a survey of U.S. state DOTs and Canadian provincial transportation agencies, interviews with U.S. and Canadian pavement marking contractors and materials manu- facturers, and a literature review. Forty state DOTs and eight Canadian transportation agencies responded to the synthe- sis survey. Reporting agencies were divided almost equally between those that now use pavement marking warranties (23 agencies) and those that do not (25 agencies). Fifteen of the responding agencies that now use pavement marking war- ranties submitted one or more examples of their specifica- tions, which are compiled in Appendix D (web-only portion of the report). These examples contributed important infor- mation to the study regarding the technical requirements, per- formance criteria, and administrative provisions that are now used in U.S. and Canadian pavement marking warranties, and how these details vary among agencies. Interviews with seven U.S. and Canadian contractors and two materials manufactur- ers, who also serve as prime contractors on jobs, provided fur- ther information on the benefits of pavement warranties, the risks inherent in their use, and ways to potentially improve their administration as well as their achievement of intended benefits. These findings are elaborated on here. CURRENT WARRANTIES AND PERCEIVED BENEFITS The 23 U.S. and Canadian transportation agencies that now use pavement marking warranties illustrate current state of practice and the different ways in which agencies structure and administer warranty specifications: • Warranty Structure and Timeline. Most agencies have the pavement marking warranty begin after mark- ing application or after initial acceptance thereof. Typi- cal durations of the warranty performance evaluation period are 1 to 6 years, with several agencies now con- sidering lengthening their warranty periods. Some agen- cies that operate roads in harsh climates or that use paint, which has a relatively short expected life, apply war- ranty periods of 180 days that are timed to encompass one winter season. • Variations in Evaluation Periods. Other agencies impose additional time periods—referred to respectively as observation periods and performance periods—to evaluate pavement marking performance through a lengthier period before initial acceptance or to allow fur- ther evaluation after initial acceptance but before onset of a multi-year warranty. • Warranty Concepts. Based on the examples pro- vided by the 15 agencies, pavement marking warranty specifications represent a blend of methods-based and performance-based thinking. A number of these spec- ifications are essentially Materials and Workmanship warranties, but with performance criteria governing minimum acceptable marking characteristics through the warranty evaluation period. Three of the state DOTs, however, employ specifications that are “pure” perfor- mance warranties, in which only the required perfor- mance from initial application through the end of the warranty performance evaluation period is specified, with choice of material and application method left to the contractor. • Pavement Marking Performance. The performance criteria specified in warranties typically include durabil- ity or presence, retroreflectivity, and color retention. Some agencies specify acceptable threshold values of these measures that are constant through the warranty period; others vary the acceptability criteria over time. Agencies also differ in how they assess pavement mark- ing performance and at what intervals. A combination of visual and mechanical sensing is used in inspections, most often conducted by agency personnel. In some cases, however, agencies call upon the contractor to per- form inspections, work jointly with the contractor in con- ducting inspections, or assign an independent third party to assume inspection responsibility. • Responsible Party. Within the warranty sample, the majority of agencies (10 of 15) regard the contractor as CHAPTER FOUR CONCLUSIONS

the warrantor—that is, the party responsible for fulfill- ing the requirements of the warranty specification. Three of 15 agencies give this responsibility to the materials manufacturer, whereas two agencies specify a dual or discretionary assignment of responsibility. In these lat- ter two cases, one agency holds the contractor responsi- ble during an observation period; the materials manufac- turer, during the warranty period. In the other instance, the agency calls for a manufacturer’s warranty bond, but—at the contractor’s discretion—allows the substitu- tion of a contractor’s warranty bond and the contractor’s assumption of all warrantor responsibilities. • Methods of Delivery. Agencies and contractors employ several mechanisms to apply or install pavement mark- ings under warranty. For example, an agency may con- tract for durable markings under its warranty provisions, but also continue to use nondurable materials that are applied by its own employees. A contractor may apply pavement markings on its own or employ subcontractors to do this work. Some states impose participation require- ments on a general contractor. A materials manufacturer is typically allowed to serve as a general contractor so long as it meets a state’s participation requirements. Materials manufacturers may themselves impose require- ments on a contractor installing their products in terms of training, certification, and onsite presence by the manu- facturer’s representative during installation. Manufac- turer’s product recommendations, participation at meet- ings, and provision of technical assistance to contractor and agency may be incorporated by an agency explicitly or by reference into its own warranty specifications. • Corrective Actions. All agencies require the repair or replacement of pavement markings that are found to be deficient according to warranty specifications. A few agencies also impose additional terms on the prime con- tractor; for example, paying cash penalties or lane rental charges, relinquishing the bond covering the work, pay- ing damages if work deficiencies exceed a certain threshold, and reimbursing the department if repair or replacement must be done by agency forces or another contractor. • Steps to Enhance Quality. Agencies use several mecha- nisms to promote quality in their warranty specifications; for example, use of qualified products lists, prequalifica- tion of contractors, stipulated meetings among all parties, Work Plan and other submittals by the contractor, ma- terials manufacturer’s training and certification of instal- lation contractors, onsite representation by a manufac- turer’s representative, incorporation of manufacturer’s product information and installation recommendations within agency specifications (if appropriate to the proj- ect), reliance upon standards and test procedures of sev- eral nationally and internationally recognized organi- zations, contractor provision of test stripes or sections, frequent contractor reporting of project status, periodic inspections, imposition of penalties for deficient con- tractor performance, and warranty bond requirements. 40 • Other Variations in Warranty Approaches and Pro- visions. Several examples of the variability in pavement marking warranty specifications among agencies were described earlier. Others were covered in chapter three (e.g., differences among agencies in whether contractors are held responsible for winter maintenance damage), and yet others are evident in reviewing the example spec- ifications in Appendix D (web-only document) (e.g., dif- ferent threshold values for minimum acceptable per- formance of pavement markings through the warranty period). • Other Issues in Administration. Several other issues in administering pavement marking warranties have been identified by the road agencies and the contractors and materials manufacturers. One topic on which the inter- ests of the two groups converge is the scheduling of par- tial payments through a multi-year warranty period. The issues concern what is a reasonable amount for initial payment and what should be the amounts of subsequent annual payments through the warranty performance period. Comments by the affected parties suggest that a balanced approach is needed to ensure that agency expectations of quality and performance are met, while providing contractors and materials manufacturers with fair, timely payment for work accomplished in the initial installation of markings. This issue will likely grow in importance as more agencies begin to use pavement marking warranties, and as the durations of warranty performance periods increase. • Cost Impacts. The impacts of pavement marking war- ranties on costs (whether initial, annual, or life-cycle) are still not well researched. Most assessments of costs are based on subjective judgments or perceptions by parties engaged in the warranty process, with little sup- porting quantitative information. The subjective assess- ments that have been made exhibit considerable varia- tion; for example, zero to 50% increase in bid price from agency sources, and zero to 20% increase from contractors, according to an earlier study of highway construction warranties in general (i.e., not limited to pavement markings). Among those responding agencies now using pavement marking warranties, almost 70% expressed satisfaction with their warranty program. About 13% reported mixed results, with concerns primarily about timely response by contractors to correct performance deficiencies. One agency that cited a “problematic” experience explained its response as really a concern with the current state of knowledge of warranty per- formance and the need for stronger capabilities in pavement marking management systems, rather than an issue with the warranties themselves. Most of these agencies categorized the benefits of war- ranties in terms of improved pavement marking performance and quality, protection against premature failure, reduced lane occupancy for repairs or re-application, and attendant

41 savings in maintenance costs and life-cycle costs (including road-user cost savings resulting from to reduced lane occu- pancy through the warranty period). Other benefits cited by individual agencies included the potential for greater con- tractor innovation, the regarding of warranties as a logical component of comprehensive departmental outsourcing, a reduced administrative and staffing burden for the agency, an opportunity to generate pavement marking performance data (which could also be used for product performance compar- isons), and a perceived positive effect of risk sharing. REASONS FOR NOT USING WARRANTIES Among the 25 agencies that do not now use warranties, 15 indicated no plans to implement such warranties in the fore- seeable future. The major impediments to pavement marking warranty use reported by these agencies were the greater administrative burden in monitoring contractor compliance with specifications, potentially higher bid prices, and possible increases in disputes or litigation with contractors. Other drawbacks that were cited included administrative difficulties associated with using U.S. federal-aid funding on projects if sole-sourcing pavement marking work and keeping contracts open on federal-aid projects while the warranty remains in force. Three agencies cited an agency culture and practice that encouraged closing out construction projects as quickly as possible, rather than an opposition to warranties per se. These agencies favored effective enforcement of project specifica- tions in lieu of warranties as the currently preferred approach to managing pavement marking performance and the risk of premature failure. Any inclination by these agencies to con- sider pavement marking warranties in the future would be addressed, but with care and deliberation. Ten of the agencies that do not now use warranties expressed an open mind toward possible future use and wel- comed additional information to help in their decision. These respondents believed that all of the categories of information listed in the survey questionnaire would be useful in their assessments (refer to Figure 15 in chapter three). VIEWS OF PRIVATE SECTOR FIRMS Private sector perspectives were obtained through interviews with seven U.S. and Canadian pavement marking contractors and two marking materials manufacturers. Most of these firms had performed work involving warranties; all were familiar with performance-based specifications and spoke from expe- rience. Although the contractors worked in different geo- graphic regions and dealt with a range of pavement marking materials, their willing participation in the project interviews may have represented a self-selected sample. Attempts to obtain a wider range of views from firms of different charac- teristics, or those less inclined toward warranties, were not successful. Supplementary findings from other studies were gathered to fill this gap. All interviewed firms believed in providing a quality pave- ment marking job, and their comments supported the notion that quality-oriented firms perform their projects to the same high standards and levels of commitment regardless of whether or not the projects involve a warranty. Nonetheless, they believed that warranties helped impose a level playing field for bidding among all participating contractors. The firms sup- ported warranties with strong but reasonable specifications that are dependably enforced for reasons of both quality of result and fair competition. This approach was believed to pro- mote use of quality products and proper installation proce- dures that yielded brighter, more durable, more consistently performing markings, with attendant benefits to the highway agency and the traveling public. Materials manufacturers interpreted project quality in terms of their own ability to exer- cise appropriate management and control of the several facets of jobs they were involved in. They believed that one-source accountability was the best approach to achieve project objec- tives, avoid finger-pointing, and yield the desired savings in life-cycle costs with benefits to agency and public. Several firms saw warranties as a wave of the future and believed strongly in their value and benefit, even though they entail risks that will be discussed here. One firm had a somewhat different, but still supportive, view of warranties as but one approach among several options to provide quality performance cost-effectively. Although this firm had nothing against warranties per se, it believed that agencies need not rely solely on warranties if high-quality materials, strong but reasonable and achievable (not onerous) specifications, and correct installation methods were called for and provided. Good techniques and products that are avail- able today can readily achieve longer, higher-performance ser- vice lives; for example, use of recessed markings in Northern climates; high-quality, durable marking materials; correct placement and application of materials (e.g., glass beads in paint); and increased specification and measurement of wet retroreflectivity. A strong relationship between materials sup- plier and contractor is very helpful toward these ends, in the view of this contractor. Notwithstanding their general support for warranties, the interviewed firms collectively identified a number of risks that contractors and materials manufacturers may face on a warranted project, and ways to mitigate them. The risks are categorized here for ease in explanation, but are actually interconnected and somewhat overlapping, and one type of risk can lead to another. Contractors and materials suppliers must deal with the total situation when deciding whether and how to bid the job. The types of risk are as follows: • Technical risks typically caused by a failure to use the right material or application method for the job, resulting in a pavement marking that fails to perform as intended. Technical risks may arise because of deficiencies in con- tractor knowledge and preparation, subpar execution at the jobsite, faults in the specifications themselves or with

agency enforcement of contract requirements, and failure to maintain proper communications among all parties. For these reasons, the interviewed firms all supported effec- tive, realistic specifications that are properly enforced. Such an approach, they believed, maintains a level play- ing field among competing contractors during the bid process and a uniform expectation of quality during the construction and the warranty period. • Administrative risks relate to problems with either the warranty specifications themselves or their administra- tion by the agency. These problems make it difficult to complete a job properly and create stresses in the rela- tionships among agency, contractor, and materials man- ufacturer. Technical risks resulting from unrealistic specifications and ineffective enforcement of technical requirements have been discussed previously. Other administrative issues that might create risks include proj- ect bond requirements, ineffective enforcement of safety requirements, lack of uniformity in agency administra- tion of warranty provisions across multiple jobs, and lack of a competent evaluation of contractors’ qualifications and suitability for future work. • Financial risks comprise two types of risks identified by interviewed firms: (1) having insufficient reserves to fund warranted repairs, and (2) having an imbalanced cash flow in which agency payments to contractors are not in step with the pace at which project costs are incurred. The interviewed firms regarded mitigation of the first risk as requiring good technical knowledge of likely pavement marking performance (including the factors affecting that performance) through the warranty evaluation period. This understanding helps guide the firms in maintaining sufficient reserves to fund repairs that might be needed. The second risk points to the need for a shared understanding between agency and contrac- tor on a fair and reasonable financial structure for a multi-year warranty project. Such a structure could pro- tect the interests of agency and contractor alike in pro- viding a proper incentive for satisfactory pavement marking performance, while reimbursing contractors for costs incurred on a fair and timely payment schedule. This issue will likely grow in importance as more agen- cies begin using warranty specifications and as warranty performance evaluation periods grow longer. • Risks to business reputation concern damage to a firm’s reputation if a pavement marking project does not turn out well. Contractors and materials manufacturers agreed: business reputation is important for maintaining good standing among current and future clients. Because any of the risks discussed earlier can have negative impacts on business reputation, mitigating this risk becomes a matter of managing the spectrum of risks identified previously. In addition to the risk-mitigation steps mentioned earlier, the interviewed firms suggested several ideas that they believed could enhance the benefits of using warranties on 42 pavement marking projects. These suggestions included the wider use of incentives for superior-performing pavement markings, with a balanced administrative approach that com- bined realistic incentives and penalties; considering war- ranties as one of a range of available options to achieve improved performance and cost-effectiveness; having materi- als manufacturers and contractors engaged to a greater degree in all aspects of project performance; improved communica- tion and dispute resolution procedures; and greater use of quality control mechanisms such as approved product lists. FHWA CONTRIBUTIONS An important role in the development and promotion of pave- ment marking warranties has been played in the United States by the FHWA. The FHWA helped sponsor the early trials of pavement marking and other highway construction warranties through its Special Experimental Projects 14 (SEP-14) pro- gram. The FHWA promotes the use of road construction war- ranties on U.S. federal-aid highway projects and supports dis- semination of web-based information on such warranties. The FHWA is meeting a Congressional mandate to develop mini- mum acceptable retroreflectivity thresholds for pavement markings. It is also conducting pavement marking demonstra- tion projects in Alaska and Tennessee to improve pavement marking durability, resulting highway safety, environmental protection, and related agency procurement processes. EUROPEAN WARRANTY EXPERIENCE The review of European warranty practice was based on recent international scans of highway agencies that were sponsored by the FHWA and AASHTO, and a review of other literature. The European warranties that were addressed applied primar- ily to pavements and thus represented general findings rather than those for pavement markings specifically. Nevertheless, these findings established differences in legal and institutional approaches between European and U.S. practice that influence the success of warranty use. European experience in road construction warranties has a long history. Materials and workmanship warranties of various durations have been used for 30 to 40 years. European coun- tries are continuing to move toward performance warranties and other methods to engage the contractor more fully into assuring the quality of asset performance through its full life cycle. Institutional differences between Europe (and to some degree Canada) and the United States include a less litigious relationship between agencies and contractors in Europe, and greater European use of bid alternatives, contractor testing, and end-result (or performance-based) specifications rather than method-based (or prescriptive) specifications. Several European countries use best-value rather than low-bid pro- curement. European agencies reinforced the importance of a best-value approach to the implementation of warranties, because it promotes trust and confidence among the parties.

43 Recommendations of the international scan teams to improve U.S. practice included the following: • To create a greater sense of teamwork between public and private sector groups. Several themes emerged in this recommendation—for example, early contractor involvement in the project development process, inte- gration of the contractor’s role within a partnering approach to meet a customer’s goals, a recognized con- tractor role in promoting quality during the project life cycle, and a willingness to consider alternative processes and methods—all of which can apply to innovative approaches to warranties. • To take actions at the federal, state, and local govern- mental levels in the United States to promote greater use of warranties, including short-term (e.g., up to 5 years) materials and workmanship warranties leading to long- term performance warranties in the future. Legislation enabling wider use of best-value procurement processes and contractor prequalification could be sought where needed. Best-value and contractor-prequalification pro- cesses could also be implemented. • To provide roles for industry in education, participation in roundtable discussions and pilot projects, and to strengthen industry knowledge and capabilities regard- ing construction and maintenance methods and products that can support warranty use. • To consider ways to accelerate identification, evalua- tion, approval, and acceptance of new products, and to incorporate these products within project specifications. The example of a European turntable for accelerated testing of pavement marking materials was the focus of one such recommendation. This recommendation is now under discussion among U.S. industry representa- tives involved in pavement markings. RESEARCH NEEDS The discussions in chapter three identified several gaps in current knowledge, including questions raised by agencies in their survey responses that suggest needs for future research. • A broader, more strategic, and more quantitative under- standing of the role and value of pavement marking war- ranties is needed. Such a research objective would tie together several loose strands in current knowledge; for example, the need for better systematic models of pave- ment marking performance and how materials proper- ties and initial installation techniques affect this perfor- mance, the impacts of pavement marking performance on road-user mobility and safety, the need for an equi- table mechanism of contractor payment, and the lack of reliable information on the relative costs of pavement marking warranties—whether initial cost, annual (or recurring) cost, and life-cycle cost. Several research top- ics can be identified and addressed comprehensively or individually: – A recommended framework for managing quality, which could be adapted to developing a better under- standing of pavement marking performance, has been proposed by Hughes (“Managing Quality” 2000). This framework emphasizes better knowledge of performance relationships, performance-related specifications, a rational basis for pay schedules, optimal levels of inspection and testing, knowing the cost-effectiveness of quality assurance procedures, and methods of quantitative analysis related to these issues. – The appropriate distribution of staged payments through the performance-evaluation period of a multi- year pavement marking warranty was raised by one of the interviewed private sector firms, and agencies now contemplating multi-year warranties are dealing with this question. This issue will likely gain increased attention as more agencies begin to use warranties and as warranty periods grow longer. Research is needed to look at financial modeling from both an agency and a private sector perspective, to provide guidance on a fair distribution of payments over time, to relate the pace of payments to accrual of costs, and to provide suffi- cient incentive for successful completion of warranted services. – Consideration could also be given to the wider use of incentives tied to superior pavement marking perfor- mance above the warranted level. This approach would provide, for example, an additional payment if actual retroreflectivity at some point were higher than the minimum acceptable level specified in the warranty. An incentive would encourage even better visibility and longer life than that envisioned by the warranty, a “do more, get more” proposition in terms of lower life-cycle costs. – Quantitative research on relative costs and benefits of pavement marking warranties would clarify existing uncertainty on the value of warranties and establish a firmer basis for determining where warranty use might be economically most efficient. – Better information on these topics could help agen- cies formulate a more strategic view of warranties; that is, as one method in a range of options to achieve the desired goals of a longer pavement marking life, improved performance during this life, lower life- cycle costs, and reduced need for road occupancy to repair or replace deficient markings. • Although all current warranty specifications contain some performance-based provisions, only three agen- cies’ example warranties in Appendix D are pure per- formance specifications that allow contractors to select materials and methods. Further research could assist agencies in understanding the advantages and disadvan- tages of performance specifications, lessons learned from agencies that have used them, and opportunities for wider use.

• Research could investigate engaging contractors to a greater degree in the pavement marking program, performing functions such as data collection needed to monitor the warranty, and processing and posting the data for segment- or network-level review and assessment. • Several agencies that do not now use warranties alluded to interactions between pavement marking warranties and other contractual or bonding commitments, includ- ing federal-aid provisions. Some agencies also perceived warranties to conflict with the desire to close out con- struction contracts expeditiously once construction work was accepted. Although it is not clear whether these con- cerns represent an actual need for research (other agen- cies had apparently addressed these types of concerns in their own warranty programs), at least wider communi- cation of acceptable procedures—for example, through roundtable discussions or peer exchanges—would assist agencies and could promote greater use of warranties if their concerns were allayed. • The interviewed private sector firms suggested basic improvements in communication and dispute resolution where they do not now exist. For example, qualified product lists could be introduced where they are not now used. As another example, a liaison committee has been established between a local chapter of the American Traffic Safety Services Association (ATSSA) and the 44 state agency to maintain communication on current issues. Formation of a panel to clarify and resolve dis- agreements was also proposed where such mechanisms are not now formalized; for example, to determine whether an infraction is serious enough to disqualify a contractor from future work. Again, this matter might be dealt with through a research study or through industry roundtable discussions and peer exchanges. • The ATSSA white paper discussed in chapter three and Appendix E (web only) raises several questions on how the United States might proceed in pursuing accelerated testing of pavement marking materials and product approvals, building on European experience with test turntables. Research to address these questions could determine whether an accelerated test facility is needed and is feasible, the role of the National Transportation Product Evaluation Program in relation to such a facil- ity, and a recommended strategy, if warranted, to develop such a facility and an agency-acceptable capa- bility for product approvals. • A comprehensive handbook on pavement markings has been produced for airfield applications. A correspond- ing handbook for highways could consolidate informa- tion on materials properties, performance histories, cor- rect application methods, and other data for reference by agencies, contractors, materials suppliers, and other interested parties.

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TRB’s National Cooperative Highway Research Program (NCHRP) Synthesis 408: Pavement Marking Warranty Specifications presents information on the use of pavement marking warranties by United States and Canadian transportation agencies, including agency specifications. European experience is also included in the report for comparison purposes.

Appendices D and E for NCHRP Synthesis 408 are available online.

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