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Facility owners and project teams often struggle to engage 'green' or 'sustainable' requirements on building projects and can incur additional project costs as a result. Although 'investments' in high performance building features can be paid back through operational savings, the project delivery methods currently adopted by most teams are laden with process waste. Lean production principles have been proven to reduce waste and improve process performance in highly complex development and production environmerits. Adopting these lean principles, this paper reports a study that identified the presence of value and waste in a sustainable building project. Through an empirical investigation of the Real Estate and Facilities Division of Toyota Motor Sales, Toyota's capital facility delivery process was mapped to identify both the steps in project delivery critical for success (value) and those that are waste. The investigation focused on the South Campus Facility, which received U.S. Green Building Council's Leadership in Energy and Environmental Design Gold certification at a project cost equivalent to a conventional facility. Through post hoc process-based analysis, insight about what added value and waste in sustainable project delivery at Toyota was obtained. The results also identify further improvement opportunities to Toyota's delivery process. For corporate facility owners and the Architecture Engineering Construction industry, the results unearth insights about how to successfully and economically deliver sustainable facilities. DOI: 10.1061/(ASCE)0733-9364(2006)132:10(1083) CE Database subject headings: Delivery; Sustainable development: Construction industry.

The sequences in which work is completed bear significantly on the performance of electrical contractors in building construction projects. When project work sequences are poorly planned or poorly executed, electrician constructors often must contend with compressed schedules, trade stacking, and out-of-sequence work to ensure timely completion of a project. This paper analytically evaluates the importance of sequence planning to efficient electrical work. It describes changes that were made to crew-level planning procedures for an electrical contractor and the impact these had on crew performance. The analysis shows that sequence planning at both the project level and the crew level are important to the performance of electrical crews. Most notably, a strong correlation (0.73) was detected between crew planning performance one week and crew productivity performance in the following week. Results of the study are provided. Principles of sound sequences and guidelines for sequence planning are also captured from the analysis. These sequence guidelines are designed to avoid, where possible, the often adverse project conditions in which electrical contractors find themselves and to handle those conditions most effectively when they cannot be avoided. DOI: 10.1061/(ASCE)0733-9364(2006)132:4(363) CE Database subject headings: Construction management; Managers; Planning; Contractors; Electrical systems.

Change orders represent one of the largest sources of cost growth on building construction projects. Field generated, or 'unforeseen' change orders can also be highly disruptive to field productivity. Design-build delivery methods can potentially help minimize change orders on construction projects. This study was performed to closely examine the effects of delivery methods on the frequency and magnitude of change orders in mechanical construction, and how design-build business practices can be used to minimize the frequency of field generated chance orders. In a study of 598 change orders occurring on 120 construction projects performed by the same contractor, the total number of change orders was found to be close to the same on design-build and design-bid-build projects, however an 87% decrease in the average number of unforeseen change orders was observed on design-build projects versus design-bid-build projects. In addition, the average size of unforeseen change orders was 86% smaller on design-build projects. A detailed and qualified presentation of the research methodology and resulting data is provided. Key attributes and business practices leading to the results are discussed and practical applications of this research for owners and contractors are provided. DOI: 10.1061/(ASCE)0733-9364(2005) 131:9(953) CE Database subject headings: Change orders; Design/build; Mechanical systems; Cost control; Construction industry.

Design coordination of mechanical, electrical, and plumbing (MEP) systems in buildings is a multidisciplinary effort to locate equipment, route distribution systems, and resolve interferences between systems that can cause field conflicts. Absent from existing research are defined metrics of design coordination--how much it costs to perform depending on project variables, and the true costs of field conflicts that are eliminated by coordination. This research was performed to explore the costs of design coordination in concert with the benefits of eliminating coordination conflicts that arise in the field. A standard method to measure costs of coordination is developed for case study projects. Potential variables that affect this cost are evaluated, and the negative impacts of field conflicts are measured. Project variables that have strong relationships with coordination costs are identified to be MEP density [MEP cost/square foot (SF)], and plenum height, and exploratory models to predict coordination costs using these variables are presented. Three distinct types of coordination conflicts are identified with measurable increasing impacts and cost. These results help to quantify the level of effort needed to coordinate building systems, and help to provide a basis for detecting projects that are likely to have problematic MEP coordination processes. DOI: 10.106l/(ASCE)0733-9364(2005)131:8(877) CE Database subject headings: Construction industry: Building design: Benefit cost ratios: Plumbing: Electrical systems; Mechanical systems.

This paper was written to fill a void created by the absence of fundamental principles of site construction management. Efficient material management is essential to managing a productive and cost efficient site. For more than 25 years, the senior author has been observing and writing about inefficient labor productivity practices resulting from poor site material management. Using deductive reasoning, fundamental principles were developed to avoid poor practices. A construction site should be portioned into three areas or zones: semipermanent (exterior) storage, staging areas, and workface (interior) storage. Each has a unique function relative to site material management. Using these areas as a framework, fundamental principles are stated and illustrated using a case study project accompanied by numerous photographs and narratives. CE Database subject headings: Construction materials; Cost control; Project management; Resource management.

The Parade Game illustrates the impact work flow variability has on the performance of construction trades and their successors. The game consists of simulating a construction process in which resources produced by one trade are prerequisite to work performed by the next trade. Production-level detail, describing resources being passed from one trade to the next, illustrates that throughput will be reduced, project completion delayed, and waste increased by variations in flow. The game shows that it is possible to reduce waste and shorten project duration by reducing the variability in work flow between trades. Basic production management concepts are thus applied to construction management. They highlight two shortcomings of using the critical-path method for field-level planning: The critical-path method makes modeling the dependence of ongoing activities between trades or with operations unwieldy and it does not explicitly represent variability. The Parade Game can be played in a classroom setting either by hand or using a computer. Computer simulation enables students to experiment with numerous alternatives to sharpen their intuition regarding variability, process throughput, buffers, productivity, and crew sizing. Managers interested in schedule compression will benefit from understanding work flow variability's impact on succeeding trade performance.

This paper describes three structural steel erection projects that used different methods of delivering the structural steel members. Two projects scheduled daily deliveries. On one project, steel was erected directly from the truck. On the second project, steel was off-loaded, sorted, and then erected. On the third project, three bulk deliveries of steel were made. The steel was stored wherever space was available, and sorting was done as the steel was erected. The differences in labor productivity are quantified using the multiple regression technique. The analysis shows that the most efficient delivery method is to erect the steel directly from the truck. Double-handling, as was done on the second project, resulted in a loss of productivity of about 9%. Indiscriminate deliveries resulted in a loss of productivity of about 16%. The effects of weather are also quantified. Significant losses of productivity occurred because of snow (41%) and cold temperatures (32%).

This paper presents a space planning method for multistory building construction. Current formal space planning in practice is limited to site layout and logistics, where space is needed for activities for extended periods of time. The space planning needed to sequence activities inside a building under construction is often neglected. The proposed space planning method is a manual method that provides a logical order and priority for space planning decisions. This helps a construction planner to: (1) identify the specific spaces needed for activities; (2) define locations for these spaces on building floors; (3) develop a sequence of work that defines the order spaces are occupied; and (4) identify potential spatial conflicts. Detail is added to the plan as needed. Through evaluation of 74 activities on four case study projects, the proposed method was found to be an accurate representation of the planning needed in multistory building construction. Two applications of the planning method identified interference problems before they occurred in the field, This space planning method offers construction managers a useful technique to develop efficient interior sequences that minimize interference and work space congestion.