Prefabrication, Preassembly, Modularization, and Offsite Fabrication in Industrial Construction: A F
The decision-making process and tool is intended to help recognize the issues to consider in making early decisions on modularization and later decisions on preassembly, prefabrication, and offsite construction. It aims at facilitating a systematic, thought-out process by providing a conceptual framework for decision-making. Although subjective in nature, the tool is designed to assist in making good, judgment-based decisions. (RS171-1, p. 18)
The Decision-Timing Map (Figure 6) and Decision-Making Flow Chart (Figure 7) were designed to identify recommended stages in the project life cycle for using the PPMOF tools.
{^widget|(containertitle)Figure+7.+Decision-Making+Flow+Chart|(name)WatermarkImage|(image)%7e%2fCII%2fmedia%2fPublications%2f171_1_figure7.JPG%3fext%3d.jpg|(widget_displayname)WatermarkImage|(width)|(height)^}
The decision framework can help identify the drivers and impediments to PPMOF that managers need to address in a project execution plan. These methods provide a spectrum of potential implementation choices rather than an “all or nothing” decision. The use of the decision framework should allow for variable timing of decision-making, consistent with pre-planning and the project life cycle. Conceptual framework for the Tactical Analysis of PPMOF alternatives is to provide a methodology to evaluate the cost impact of PPMOF strategies. It is for use during conceptual design and at the beginning of detailed design. (RS171-1, p. 25)
Tactical framework focuses on the cost-per-unit level of the project. In general, the conceptual framework for Tactical Analysis consists of a series of tasks for making cost comparisons. (RS171-1, p. 28)
Schedule and Labor Comparison – Provides an example of the difference in schedule between an all stick built project and modularization. In this example there was a savings on the front end and two on the back-end due to PPMOF. The example was based on relocating 40% of the hours offsite with PPMOF. Building consensus on cost benefits of the schedule reduction and relocation is a challenge to overcome. The owner, contractor, and engineering should share cost and financing data, adequate quantification of schedule cost benefits.
