IPD facilitates project changes
A collaborative BIM process provides the ability to respond faster to unexpected modifications to a project, says buildingSMART ME president TAHIR SHARIF.
01 April 2011
PROJECTS are never simple, but some are more complex than others. For example, a specialist hospital that requires an intricate design right from the outset, is also predisposed to a need for changes later in the construction process.
Incorporating such modifications requires the ability to react quickly. For this to be possible, in addition to a flexible design process, there needs to be an environment conducive to collaborative working, so that the entire project team can together meet challenges.
To respond quickly and effectively to changes, the business process needs to have technology in place and the willingness to address the problems. Integrated project delivery (IPD) and collaborative contract forms provide an environment to facilitate change.
The principle problems associated with the traditional design process and contracts and the solutions suggested by the collaborative BIM (building information modelling) process are discussed below.
Design process
The five key stages of the design process including spatial design, which is early or concept design; preliminary construction design, a model that defines basic quantities, areas and volumes; construction design, where products to be used are defined in generic form; product design, where specific products are defined; and maintenance design, also referred to as the ‘as-built’ design, representing how the project was actually built.
Skilled professionals are required to complete the design process including architects, structural engineers (steel, precast and cast-in-situ concrete) and mechanical, electrical and plumbing engineers. Each will create his own designs and critically each design will have an impact on the other. Designs have to be transferred between the multiple disciplines. The inevitable result is that some data is lost or misinterpreted. The designs also have to be co-ordinated to ensure that trades do not overlap with their products or services.
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The St Clare Health Centre project. |
And of course design teams use different software tools to create their designs and those can be any combination of schematic, 2D, 3D and BIM, many of which do not communicate with each other, necessitating manual interpretation and thereby creating a whole new source of potential errors.
The designs are also used as the basis for the cost, planning and facilities management teams to perform their services.
The preferred BIM approach – IPD
Using BIM processes and tools, it is possible to complete the five key stages of design in a single model.
Moving from one stage of design to the next in the BIM environment has been described as ‘model progression’ but the process is now more correctly defined as IPD. This process gives operatives the opportunity to work in a single environment with the objectives of improving efficiency and eliminating errors. Furthermore, it provides technology and processes that provide the ability to react to changes.
Choosing the contract route
Deciding on the type of contract to use can have a major impact on how relationships develop between key players and ultimately, on the project outcome. While choosing the correct contract from the array on offer can be daunting, it is critical to ensure that processes such as BIM and IPD can be incorporated and capitalised upon.
The three parties involved in a typical construction process are the owner/developer, designer and builder, who have to work within local government regulatory guidelines and also be able to communicate with building and facility managers.
The construction management remit encompasses numerous activities. However whatever the remit, the project or project element will require parties to commit to a delivery structure defining roles and responsibilities of the management team, communication protocols, project controls and procedures for disputes and claims. These are defined in the contract.
Delivery methods & contract forms
Traditional: For decades, the most common project delivery also known as design-bid-build has incorporated two contracts. The first contract is between the owner and designer, broadly covering planning, design and construction administration. The second is between the owner and successful bidding contractor, covering the actual building activities.
With the traditional method there is no formal contract between the builder and designer, resulting in an indirect third-party relationship between them, which does not help the communication process.
Design and build: This combines activities of the design and build teams into a single construction team who have a common contract with the owner. They take a concept design from the owner and complete the detailed design. This is then submitted to the owner for approval. Once approved, the design-build team completes the additional stages of design (construction/production/maintenance), in parallel with the actual construction process. This contract has two significant advantages over traditional delivery:
• Constructability is optimised because design and build teams are motivated to work together: and
• Build time is significantly reduced due to the involvement of the contractor in the design process, allowing early mobilisation and concurrent construction.
This contract form enables the effective use of collaborative technologies and is well suited to BIM/IPD processes.
Construction management (CM) at risk: This is a more advanced form of collaborative project delivery. A contract is established at the outset of the project between the key players, enabling the creation a true construction management team.
Concept and evaluation are combined as a ‘pre-construction’ service, enabling all parties to exercise their particular skills in establishing the starting parameters for detailed design and construction.
Parties are often able to commit to project delivery within a ‘guaranteed maximum price’. This fundamentally changes the relationship of the contract parties – they have a common financial incentive to maximise the efficiency of the project delivery to minimise risk and maximise reward. As collaboration is the basis of a CM at risk contract form, it enables the advantages of BIM and IPD to be fully utilised.
IPD
Any contract form that provides a platform for cooperation and collaboration will promote the willingness of parties to meet the challenges of change.
The American Institute of Architects’ (AIA) definition of IPD reinforces the fact that for optimal results, IPD needs to be linked to a collaborative contract form: “...a project delivery method distinguished by a contractual agreement between a minimum of the owner, design professional, and builder where risk and reward are shared and stakeholder success is dependent on project success.”
Linking IPD with contracts
For projects that are likely to experience significant change, combining IPD with such contract forms brings significant benefits. It provides a technology platform to facilitate the mechanics of change and incentives for all involved to seek the optimum solution.
However, to ensure that the IPD process is correctly embedded into contract, it is necessary to clearly define the key requirements for successful IPD in any subsequent contract.
The methodology used by the AIA to assess a number of case studies determines criteria for success. It uses a ‘scorecard’ approach, which effectively provided a way to measure and compare performance.
The characteristics identified as fundamental to IPD include: early involvement of participants; shared risk and reward; multi-party contract; collaborative decision-making; and liability waivers.
In addition, other characteristics were considered highly desirable for IPD such as: mutual respect and trust amongst participants; collaborative innovation; intensified early planning; open communication within the project team; BIM used by multiple parties; lean principles of design, construction and operations; co-location of teams; and transparent financials.
‘Key participants’ included the owner, architect and builder, as well as design consultants and subcontractors who sign ‘joining agreements’ and are included in the shared risk and reward structure. Disciplines and trade contractors whose input has the most impact on project design and costing are considered the most valuable early participants. Project data was provided by each project and lengthy interviews with project participants were undertaken.
The case studies illustrated how IPD is most successful when owners, architects, engineers, and builders step outside the boundaries of traditional roles into a more fluid, interactive, and collaborative process. Documents generated from a single BIM model may be used for permitting, analysis, bidding, fabrication, and more.
Fundamentally, it is evident that traditional roles have to change in order for the inherent benefits of IPD to be realised.
Case study
One such case study of the St Clare Health Centre project demonstrates the benefits of combining collaborative contracts with IPD. The 40,000-sq-m replacement hospital in Fenton Missouri, US, comprises a 154-bed inpatient tower, a 7,900-sq-m medical office building, a 7,000-sq-m ambulatory care centre, an emergency room and other diagnostic and surgical components. Owner SSM Healthcare worked with HGA Architects and Engineers with the intention of enhancing patient experience by designing a conceptual two-storey ‘main street’, with separate areas representing a marketplace, hotel, factory, healing garden and condominium.
St Clare was the first IPD project that SSM and Alberici took from conception, while HGA had prior IPD experience in this type of project. A primary reason for the choice of IPD was the complexity of healthcare design and construction.
Donald Wojtkowski, executive director design and construction, SSM Healthcare, said: “The only way you’re going to get the complex design and construction resources needed for a project like St Clare and get them to change their behaviour, is to remove financial risk. Whenever you have a GMP (guaranteed maximum price) or stipulated sum, if you need to deviate from the schedule for the good of the project, you’re going to get a change order and be arguing about it for the rest of the project.”
At St Clare, the owner decided to switch from back-to-back patient rooms to same-handed rooms, even as structural steel was being erected. This decision came from studies showing that same-handed rooms promote operational efficiency and reduce the likelihood of medication errors.
It was decided to make the change even though it increased cost. Such a major change so late in the process would have been extremely difficult for a traditional, fragmented design and construction team to handle efficiently, but the integrated team was able to meet the owner’s wishes because of its inherent flexibility. The change was made without a major impact on cost or schedule.
Project delivery
Having decided to use the process of integrated delivery, all parties worked together using BIM processes and technology. These were used extensively, not only to detect clashes between systems, but to increase the proportion of prefabricated assemblies with their greater tolerances and lower requirement for field labour. The collaborative environment was enhanced by the process of ‘Big Room’, that is, a physical environment where stakeholders work together using BIM technology to drive the project.The ‘Big Room’ was in fact a triple-wide trailer set up on the site.
Alberici project director Tim Gunn said: “All the time spent up front in the Big Room was more than paid back later with substantially fewer coordination errors and RFIs (requests for information).”
Kevin Kerschbaum, project manager, HGA said: “We could have drawn it all but we wouldn’t have known if there needed to be a joint here or a piece of unistrut there. You have a much higher degree of certainty that things will fit when the actual fabricator is doing the modelling. Everything should be drawn and detailed by the right person at the right time and then put together into the overall model.”
Virtually all systems including power, low voltage, lighting, mechanical and fire protection were modelled in detail.
The ‘Big Room’ was augmented with a project management web site used to share design progress with team members who could not physically be present.
