Water Design-Build Council Blog

How Does CMAR Differ from Design-Build?

41662236_s.jpgEarly contractor involvement. (That’s good!) Constructability input with my engineer. (That’s even better!) A qualified contractor that knows the project before heading to the field. (That’s the best!)

In light of these and other Construction Management At-Risk (CMAR) benefits, we often get asked, “How does CMAR differ from the other design-build delivery methods?"

There’s no doubt that CMAR is a proven, viable project solution for many utilitiesand in many geographies, a similar methodology is called  a "general contractor/construction manager” or "GC/CM." WDBC’s member firms successfully build CMAR projects, too — and CMAR is part of the “collaborative delivery” family. Sometimes CMAR is even called “design-build light.” 

However, there are significant differences between CMAR and design-build. CMAR is fundamentally a traditional design-bid-build delivery method at its core. It leverages some of design–build’s preferred collaboration focus, but performance responsibility on the part of the engineer and the contractor remains distinctly separate. Ultimately, the Owner must still adjudicate between design and construction issues. This nuance can at first appear to be subtle, but consider these three major impacts to your project:

  • Standard-of-Care vs. Commitment to Performance. In CMAR, engineering solutions remain bound to an industry Standard of Care criterion — the design should function as envisioned, but the obligation, in layperson’s terms, is to have tried as hard as the next person would have tried. In contrast, design-build contracts enforce an obligation for a solution to perform to an agreed-upon standard. And further, if the solution does not work, the design-builder is contractually committed to making things right.

  • Teamwork vs. Integration. Teamwork under a CMAR model is great, but it ultimately requires people from separate companies — with fundamentally separate business interests — to work together as best as possible under separate contracts. Design-build is performed under a single contract that integrates the business and delivery interests of a design-build team. (And, in the case of WDBC members, under the auspices of a single-entity design-builder). So, do you need more design effort to reduce construction cost? Need to adjust for some scope left out of an estimate because the design detail was missing? Want to compare several construction methods with different engineering requirements? Integrated design-builders solve challenges like these without the need for an owner to play referee.

  • Build-as-Designed vs. Build-to-Perform. Genuine design-build integration extends beyond the pre-construction phase. CMAR serves many owners well in getting contractors to the field after early input to the design. But once the construction has started, the contractor's obligation is to build the project according to the plans. When there is an issue with the design, there is likely to be a change order. Alternatively, design-builders use plans as a means to an end: producing a completed facility that functions as promised — without the risk of contractor change orders. (It's actually rather funny to think about such a situation. As a design-builder, would I send a change order to myself?).

The bottom line is that there is plenty of room in our industry for all sorts of delivery models. CMAR is a good approach in the right circumstances, and we think design-build is an ideal solution for owners that want a commitment to performance. Yes, CMAR and design-build are indeed different. Think about it this way: CMAR is like living with a great college roommate, but design-build works like a great marriage.


Topics: CMAR