Chapter 3 Discussion Questions (Continued)
4.4 HOW OWNERS BUILD
initial fi rst - costs to delivery models that optimize the overall building delivery and yield quality facilities based on reliable costs and schedules. Consequently, serial owners tend to represent a high proportion of early BIM adopters.
One - time owners, though, can benefi t just as much as serial owners and can do so easily by collaborating with design and construction providers famil- iar with BIM processes. Many of the case studies discuss projects where a serv- ice provider initiated the use of BIM.
FIGURE 4-12 The traditional organization of a project team involves contracts between the owner and the primary architect and builder, who in turn maintain contracts between these organizations and sub-consultants.
This type of contracting often prevents the fl ow of information, responsibility, and ultimately the ability to effectively use BIM tools and processes.
Owner/Client
Architect
Typical Organization of Project Team (Single stage, traditional)
General Contractor
Engineers and other
designers Subcontractors Fabricators
Building Product Suppliers
Lines represent typical contract relationship
Relationships needed to build an integrated building model or use
BIM process
FIGURE 4-13 Diagram comparing three different delivery processes.
A) The traditional single-stage involves the completion of each phase prior to the start of the next phase, often involving a different organization performing each phase in a non- integrative process; B) the design-build process involves an overlap of development phases leading to a shortened overall schedule and requires integration between designers and builders;
c) a collaborative process involves participation by all key participants as early in the process as possible and ongoing collaboration.
Feasability
Feasability Bid
Bid
Feasability
Build
Concept Development Documentation
Design
Concept Development Documentation
(A) Design-Bid- Build(B) Design- Build
PROJECT TIMELINE
(C) Collaborative
Bid
Build
Operate
Operate
Pre-Construction Construction
Concept Development Documentation
Pre-Construction Construction
Pre-Construction Construction
Bid Operate
time savings due to parallel design and
construction Design
Design
Construction
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of technologies or processes across the project team, due to the many contractual divides. Typically, this process is defi ned by the “ wall ” of deliverables whereby at the end of each phase the deliverables are handed “ over the wall ” with little or no integration or collaboration between the participants in each phase. The deliverables are typically paper - based. Often at the start of each phase, infor- mation is re - created or duplicated, reducing the value of project documenta- tion and resulting in a loss of project knowledge (See Figure 4 - 1 ). Contractors or their subcontractors and fabricators often re - draw architect ’ s construction documentation in the form of confi guration drawings, because the architec- tural and engineering drawings do not dimension or lay out spaces or detail the connections needed for sub contractor coordination.
This deliverable - based approach makes it diffi cult to successfully imple- ment those BIM tools and processes that require a model - based handover between organizations; in these scenarios, the organizations agree a priori on the format and content of the model itself. For this reason, BIM application in a DBB project is often limited to single phase BIM applications, such as 4D or energy analysis. An owner, however, can expand the potential BIM application on DBB projects to include:
1) Contractual requirements specifying the format and scope of the build- ing model and other information at each deliverable phase
2) The cooperation of individual organizations to support or promote the BIM process within their own phase
4.4.2 Design - Build
As discussed in Chapter 1 , an increasingly common model of facility delivery is design - build (DB), where a contractual relationship is established between the owner and a single organization and often represents the architect and builder either as a single company or as a partnership. In design - build, the individual phases are not necessarily shortened, but the overlap of phases reduces the overall project duration, as shown in Figure 4 - 13(B) . In some cases, the integration of construction details earlier in the process can inform the design and lead to improved coordination and constructability and reduced construction time.
Studies comparing these approaches conclude that the DB process does have benefi ts in terms of project timeliness and schedule reliability (Debella and Ries 2006; Konchar and Sanvido 1998; USDOT - Federal Highway Administration 2006; Ibbs et al. 2003). The Konchar and Sanvido study found benefi ts of DB in terms of cost and quality, but other studies do not show signifi cant cost or quality differences between the two approaches. The DB
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delivery process creates a potentially smoother fl ow of information between design and construction organizations. It still requires that organizations (or groups) spend time at the beginning of the project to defi ne the work process, build and maintain the building model, outline its specifi c uses including scope and responsibility of each participating organization, and test the process.
Unlike the DBB method, where such collaboration is often limited to specifi c handover periods or deliverables, the DB team can collaboratively identify BIM applications across project phases and focus less on specifi c deliverables between organizations and more on overall deliverables to the owner.
Section 4.9 provides some guidelines and tips for owners wanting to promote a successful BIM effort.
4.4.3 Collaborative Process
A third and new approach to procuring a project is a variant of the design - build, has yet to be named, and emphasizes a collaborative, alliance - based relationship between owner and AEC service providers. A study by the University of Texas (Geertsema et al. 2003) documents a signifi cant shift in non - collaborative and collaborative relationships between owner and contrac- tors from “ winning bid fi rst use ” to “ alliance preferred provider. ” That is, owners are moving away from the traditional selection of providers based on ‘low - bid,’ which is common in DBB scenarios, to preferred providers. The same study notes that the projects with collaborative relationships are more successful from both the owner and contractor ’ s perspectives.
This collaborative approach involves the selection and participation of all key project participants as early in the process as possible, either with single prime (representing multiple organizations) or multiple prime contractual rela- tionships. Figure 4 - 13(C) shows how this process may occur during the feasibility stage, when the participation of service providers potentially has the greatest impact and can help defi ne project requirements. Where the design - build process typically involves a partial overlap of designers and builders, the collaborative process requires overlap beginning with the project ’ s initial phase and by more participants, requiring more intimate involvement of the owner or owner ’ s representative. The collaborative process may not necessarily yield a shorter overall project duration or earlier start of construction, as shown in Figure 4 - 13 , but it does achieve participation of the construction team, includ- ing fabricators and suppliers who are involved early and often. This approach is often combined with incentives for the entire project team to meet specifi c project goals and targets and also involves risk sharing. The primary difference between this process and the design - build approach is the collective sharing of risk, incentives, and the method of creation of facility documentation.
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The collaborative approach is an ideal procurement and delivery method for reaping the benefi ts of BIM applications on a project. The participation of all project participants in the creation, revision, and updating of the building information model forces participants to work together and virtually build the project.
The technical challenges discussed in the previous section will persist, and owners along with the entire project team should follow the guidelines in Section 4.9 to maximize the team’s effort.
4.4.4 Internal or External Modeling
These different procurement methods do not address situations where own- ers perform some or all of the design, engineering, or construction services.
Outsourcing is a common trend for many owners (Geertsema et al. 2003).
There are some owner organizations that have construction management and construction superintendents on staff. In such cases, as discussed in Section 4.9 , the owner must fi rst assess their internal capabilities and work processes. The “ wall ” of deliverables can exist internally, and defi ning model handover requirements between internal groups is just as critical. The owner must ensure that all participants, internal or external, can contribute to the creation, modifi cation, and review of the building model. This may involve the owner requiring the use of specifi c software or data formats to exchange data.
Outsourcing, however, does have an impact on the overall BIM effort, and owners who choose to hire a third party to produce the building information model independent of the project ’ s internal and external team of service pro- viders should carefully consider full outsourcing of the model. Typically, the outsourcing effort leads to a building information model that is under - utilized, outdated, and of poor quality. This occurs for several reasons. First, the internal or external team has to reach a specifi ed point in the project to hand over the traditional documentation. Second, the outsource team must spend signifi cant time, often with little contact since the team is now busy working towards the next deliverable, to understand and model the project. Finally, the outsource team does not typically have highly - skilled or experienced staff with building knowledge. Thus, outsourcing should be done with considerable attention and management oversight or used as an effort to support the BIM effort, not replace it. The One Island East Offi ce Tower case study is an excellent example of working with external resources to develop the building model while integrating its resources into the project team both physically and virtually. Another example is the Letterman Digital Arts project in San Francisco, where the owner hired an outside fi rm to build and maintain the
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building model (Sullivan 2007). In both cases, the critical success factor was attributed to bringing the resources onsite and mandating participation by all project participants.