EPC (Engineer-Procure-Construct) and Design-Build have both existed as mainstream delivery methods for decades, but what's the difference between the two? If anything, they seem to share critical similarities. In both cases, the owner has a single point of contact on the construction side. In both cases, the contractor is responsible for the design. In both cases, the contractor takes on more risk than a traditional design-bid-build delivery. But several key (if sometimes subtle) differences differentiate the two:
An EPC project typically results in a turnkey facility. At closeout, the EPC contractor hands over a working facility that's ready to go. A design-build contract closes out similarly to design-bid-build contracts, with the owner and its construction manager or designer taking an active role in punching out the facility. EPC contractors are often handed little more than performance requirements (output levels, uptime levels, maintenance expense maximums, etc.), whereas most design-build contracts provide at least some design detail in the bridging documents. There is no EPC equivalent of the “design-assist” or “fast-track” design-build processes. Once again, this reflects the owner's more minimal involvement in the EPC design process. Many contracts transfer far more risk to the contractor in an EPC delivery. Design-build contracts tend to take either a traditional design-bid-build approach to unknowns like hidden site conditions, or to share that risk between the owner and the design-builder. In contrast, it's not uncommon for EPC contracts to shift these risks entirely to the EPC contractor.
Understanding the differences between these two seemingly quite similar design processes is a key step when assessing which delivery system is right for your project.