By Chris Marks, Burns & McDonnell
If an Owner is restricted from leveraging the advantages of a full Engineer, Procure, and Construct (EPC) approach for a project, they still need to carefully consider their options in the Design, Bid, Build space.
One of the first options is the selection of a design approach and firm. Not all design firms and philosophies are the same and may significantly impact the successful execution of a project. However, investing in a full detailed design effort has many advantages over engaging a firm to create performance specifications for delegated design by a contractor. These advantages include better opportunities for budget control, a final product that more accurately reflects expectations, and more streamlined construction.
Scope coordination efforts should lie with the Design Bid Build Engineering Team and not a construction Team.
When engaged in a full detailed design effort, the engineering firm takes on full responsibility to perform the coordination effort needed among the various design elements. This means that the engineering firm should be fully investigating and defining any existing utilities, equipment procurement contracts and subcontractor packages. By relying on a contractor to perform all coordination, the project becomes limited in its options, as any items that are not in the contractor’s scope become risk items that may not be fully coordinated.
One of the consequences of this, however, is that any equipment or subcontracts will have an associated markup passed along to the Owner. By performing full detailed design before contracting for equipment procurement or installation, the Owner leaves all these options for cost savings and risk mitigation available to the project. It is often advantageous to select multiple subcontractors, each performing the scope that falls within their expertise, whether it be building erection, piping fabrication, or electrical installation. In fact, this is the approach that will likely be taken with a single installation contractor as they subdivide their work among subcontractors.
A full detailed design effort will not only identify these opportunities but effectively and efficiently define scopes as needed to contract directly with these firms without leaving gaps that would need to be addressed through other subcontracts or change orders. The scope and number of the contracts can be further refined to match the contracting capabilities of the Owner. Oftentimes, this results in significant cost savings for the Owner as they are able to contract directly with these firms to get the best pricing without markup.
Early definition provides owner control and input.
By going through the effort to define these work scopes for the subcontractors, the Owner also gets additional time and opportunity to fully define and have input on the design of the project. A typical package for a single installation contractor will not have the same level of design, as much of that is delegated to the contractor. The contractor would be responsible for final fit-up to all equipment and the associated utility corridors that are necessary. Some of this may change significantly by the end of the project and may result in arrangements of piping, raceway or equipment that are not ideal for planned maintenance activities.
However, a full detailed design effort will continue design and coordination through the equipment procurement process, thus defining all these items and working through any challenges or unexpected developments as a team with the Owner. This allows for full input in the problem-solving process that would otherwise be lost if this design and coordination were delegated to the subcontractor. This has the additional benefit of creating a more constructible project model that is ready sooner, more accurate and less likely to change during construction.
Furthermore, this allows for identification of opportunities for cost savings from increased modularization and shop work for various areas and assemblies that shifts labor from the field to the factory, which typically provides cost savings to the project.
Engineering teams with execution experience can save your project time and money.
Another significant advantage is that the full detailed design effort can identify significant coordination points and challenges that would normally result in RFIs, delaying work and causing inefficiencies during construction. This is especially true if the engineering firm executes work as an EPC or has significant experience managing direct-hire construction activities.
As RFIs are the result of unexpected conditions, performing a full design effort reduces the number of these “unknown unknowns” that add risk and potential cost to a project, providing needed solutions or mitigation techniques. For example, being able to fully design all electrical raceway along with the as-manufactured switchgear and arc flash plenums will allow for a more efficient design that avoids interferences and allows sufficient space to access raceway and pull cable, which becomes more critical as more prime movers and associated generator leads are added, such as in a RICE-based power plant.
Furthermore, with the objective in mind of reducing RFIs and coordination in the field, the detailed design firm should have greater accountability, as they are still engaged in the project during construction to address these issues as they arise.
There are numerous advantages to investing in a full detailed design effort instead of relying on an installation contractor to perform necessary coordination for the project. An Owner would be well-served to consider the potential benefits to cost, risk identification and mitigation, maintainability, and constructability that performing a full detailed design effort can provide a project.
About the Author: Chris is the Mechanical Department Manager in Burns & McDonnell’s Chicago office. He specializes in the design and execution of reciprocating engine power plant projects. He also has experience in the design of natural gas-fired power generation facilities, power generation site water removal systems and plant controls.
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