Alternative Delivery Methods

A Little Design-Build Goes a Long Way

by Paula Widholm

Owners that like parts of design-build but may not be ready or able to use it completely have the option of modifying the method and applying some of its parts to traditional projects.

‘Design-Build Lite’

Chicago-based James McHugh Construction Co. often uses a version called “design-build lite” where mechanical, electrical and plumbing, and sometimes structural operate in design-build mode while the rest of the job is performed under traditional plan and spec, says Bob Soldan, vice president.

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Under this system, either McHugh or the owner provides performance specifications, and the MEP subcontractors design their own respective work. Under traditional design-build, the designer-builder is responsible for designing everything on the job based on the owner’s performance specifications or conceptual drawings.

Design-build lite “can decrease a certain amount of the owner’s design costs,” Soldan says. “Typically, under plan and spec, the architects and engineers design the whole system and then the subs have to come back and design it again.”

With design-build lite, the project gets a jumpstart.

“You don’t have to wait for the engineers to prepare construction documents for bidding,” Soldan says. “You can start design and coordinate it during the preconstruction process. We can get shop drawings done and equipment ordered before we break ground and coordinate MEP issues before we even start the job.”

It also reduces owner risk on the MEP side, he says.

“When you have a plan-and-spec job and the owners and engineers are responsible for full design, if there’s a problem, you have to ask, ‘Was it the engineer’s design or the subcontractor’s installation?’” Soldan says. “Now, you’ve got a single point of responsibility. The subcontractor is not just the installer but the designer, too. You can go back to them with any issues in the system.”

Getting subs on board early helps value engineer with the designers as well as get better prices on materials and equipment, Soldan adds.

He estimates that 75% of McHugh’s MEP work is done design-build lite.

Performance Specification

Similarly, the Illinois Tollway uses performance specification on a majority of its projects, including on its noise walls.

The most notable use was on the Des Plaines River Valley Bridge on the new south extension of Interstate 355, where the Tollway saved millions of dollars by choosing Walsh Construction Co.’s design to performance specifications.

“We gave the contractor the option of bidding to the performance specifications or on two fully designed options,” says Paul Kovacs, chief engineer of the Tollway. Walsh chose the former.

Without performance specification, “the Tollway would have to spend time on the design of a project, which could take up to a year, and then go out to bid, then into construction,” Kovacs says. “When we use performance specification, we get our jobs out to bid faster.”

The Tollway is required by procurement code to advertise its construction contracts and award them to the low bidder.

“We still do at least 30% of the design effort before we advertise it to the contractor,” Kovacs says. “We’re still contracting with a designer and a contractor whereas with a design-build contract, one guy does everything.”

On noise walls, the Tollway determines height and location, but “we leave the rest of the design up to contractor as far as what type of noise wall and how he wants to build it and what the foundation will look like,” Kovacs says. “We have our designer prepare guidelines for materials and appearance but the contractor can use his own method. By allowing flexibility, the contractor typically gets better prices.”

Performance specification also allows the contractor to work with its own people, have time dedicated solely to design and work on other parts of the project while completing the design, Kovacs adds.

The feedback from contractors on performance specification has also been positive, Kovacs says.

“We’re not dictating everything, and they feel like they’re more part of process,” he adds. “As long as you can describe what you want to get at the end, you can utilize a performance-based specification.”

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