Maximizing modular: How the emerging building method is gaining ground in construction

With the planned 1800 Terry building in Seattle, Kirkland WA-based Seawest Investment Associates is gunning for the first urban high rise project to be awarded a priority green building permit from the Seattle Department of Construction and Inspections. By the numbers, 1800 Terry will feature 38 stories topping out at 440 feet, 424 rental units with floor plans up to 930 square feet per unit, 8,000 square feet of retail space, parking for 259 vehicles and 1,652,148 screws.

It’s the screw count that has Arlan Collins excited. As principal and co-founder of Seattle-based architecture and planning firm CollinsWoerman, Collins calls 1800 Terry a “version three” iteration of the firm’s modular construction vision. The precision in material selection and procurement — down to the last screw — is one of many factors contributing to a project estimated to consume half the energy, generate half the waste and take half the time to build as a comparable, traditionally constructed building.

Utilizing offsite manufacturing facilities, modular construction seeks to prefabricate wall panels and other building components for final assembly on the job site. By placing production in a factory environment, modular building promises more efficient construction, boasting reduced waste and faster builds with smaller teams, all contributing to significant project cost reduction.

“We founded the firm to integrate design with construction to remove waste in the process,” Collins said. “Buildings come in over budget, customers are irate and the structure of the industry is a mess and needs improvement. Where we have repetitive diagrams in place, writing down half of everything in the process was a goal we thought we could attain with modular construction.”

Particularly for asset classes with high repetition in floor plans — think multifamily, hotel and health care projects — modular building is seeing increased investor interest for the cost savings generated by lean production. Yet it faces implementation hurdles that could offset benefits for stakeholders unprepared for the myriad differences from traditional construction apparent from the project's start. 

The magic and the misery

Roger Krulak is the CEO and founder of Brooklyn, NY-based Full Stack Modular and perhaps the lone survivor of 461 Dean, a modular construction partnership between Forest City Ratner Companies and Skanska USA that was mired in delays and arguments over process and devolved into litigation. Although the completed 32-story project, located in Brooklyn, is currently the world's tallest modular high-rise, lawsuits are still pending. Forest City sold its modular building factory to Full Stack Modular in October 2016, effectively exiting the modular construction market.

Despite the snags, Krulak — who manned Forest City’s modular division while it existed — remains a firm believer in the Brooklyn factory’s ability to supply marquee mod projects across the Big Apple and beyond.

“It has been an effort to change an industry that has had no change to progress and productivity in a long time,” Krulak said.

“Everyone was looking at 461 Dean Street as a proof text for modular, but the real challenge was how the partnerships worked with two large, entrenched companies with divergent cultures attempting to solve a startup situation. That was the misery, not the technology or the process or the product itself.”

Indeed, modular builders stress that both owner and designer engagement in a modular project from conception onward is critical to market success. The earlier investors, architects, component fabricators and general contractors can agree to and collaborate on the process, the more likely modular projects are to enjoy the product quality, build speeds and cost containment the method promises.

Dulles, VA-based Southland Industries is one of the country’s largest MEP contractors, and it is expanding into modular manufacturing to help solve construction issues for complex, fast-tracked projects.

“If you want to influence mod or prefab to its maximum capabilities, you need to start thinking about it much earlier in the process,” said Mike Miller, Southland's Mid-Atlantic division leader. “I can modularize an entire chiller plant offsite, take it apart, bring it into the job site and put it back together if we do it early enough in the process." Waiting until the design is complete, however, can limit modular's impact, he said.

Systems and software

While modular projects need early stakeholder buy-in, the systems and technologies are often the same as the CAD and BIM platforms used in traditional construction. While some builders have adopted design and manufacturing software from other industries or have built programs in-house for managing product across the build cycle, those systems don’t differ substantially from typical 3-D design and engineering software already available to the AEC industry.

CollinsWoerman, for one, has looked to the nearby Boeing aircraft factory in Everett, WA, for manufacturing best practices, adopting that firm’s use of Autodesk Inventor production software and even recruiting Boeing workers to fabricate building components. From there, Collins said, on-site panel assembly is completed by a steel erector and a small crew. The firm’s 47+7 project, a six-story, 24-unit apartment building comprising studios and one-bedroom units, in Seattle, was completed in five months. “In hindsight we think we could have done it in 90 days as we continue to see the collapse of time on these projects,” Collins said. “Any pipe fitter that knows how to put together pipe can do it, any electrician that can do standard connections can do it.”

Calgary, Alberta, Canada-based DIRTT Environmental Solutions is focused solely on the modular interiors market, providing MEP-engineered panels for customizing commercial and residential project floor plans. The company's co-founder and vice president of software development, Barrie Loberg, said the need for end-to-end design programming led to the creation of the firm’s ICE 3-D design software, which creates wall panel schematics for factory construction. “We did look to purchase software first but didn’t find a system simple enough to put in front of customers on the design side but complex enough to get the cost and fabrication of product optimized in the plant,” Loberg said.

Given a 3-D building model, modular production software generates material lists, pricing and optimizes construction steps for download to CNC machines on the factory floor. Matched with human fabricators, CNC machines cut wall panels to size and drill holes for MEP components. Workers assemble the final product with screw guns.

At its Brooklyn factory, Full Stack uses off-the-shelf AEC design software (Krulack declined to specify the brand) to power 85,000 square feet of production space, including two 700-foot-by-120-foot production bays and two 40-foot exterior doors, adjacent to a dry dock with 240,000 square feet of storage space for finished modular units.

While CollinsWoerman likewise leverages CNC technology in the firm’s production facilities, the company doesn’t see modular construction going fully robotic, particularly given the low costs already achievable using manual labor. Still, the firm uses 3-D printers for prototyping all projects to engage stakeholders early in the design and engineering process. “You need some serious volume before you’re investing in robots,” Collins said.

Despite modular's perceived simplicity, its specialists must focus on precision in the factory. DeSimone Consulting Engineers uses Revit for most of its modular projects and often partners with PolCom Modular, which builds all of its components in Poland. “These projects want to be done in a BIM system,” said Michael Schwarz, an associate at the company's New Haven, CT, office. “You’re dropping sequential pieces into place and everything needs to match up, particularly when mods are being shipped from a distance.”

Repeatable processes, recyclable buildings

Achieving modular construction’s time and cost-savings requires moving repeatable processes off the job site and into the factory environment. “From a total development cost, including money out, early revenue, decreased material and safety cost, less deliveries, we believe you’ll save between 20% and 30%,” Krulak said. Modular is also quiet. Once the foundation is in, scaffolding assembly is not required and there can be a significant reduction in construction-related noise.

Offsite fabrication also allows multiple building phases to be underway concurrently. As a foundation is being poured or a podium is being built, for example, the rest of the structure can be taking shape in the factory. “It’s a key aspect of the time savings in modular, the ability to lay slab at the same time you are manufacturing the modules, and then you can just drop them right in,” Schwarz said.

Modular capabilities are also advancing to include complex building mechanicals, which could open the door to projects with less repetition in design. For example, Southland Industries is working on projects with modular-built telecom closets and even modular bathrooms.

According to Miller, as long as design specifications are correct and reliable, modular builders have the capacity to approach nearly any project design. “If you know it is going to fit when you get out there, the entire process is easier to control, allowing float in the construction schedule and minimizing crew sizes accordingly,” he said. “It is a concept of production where the guys in the field are becoming expert speed installers rather than being craftsmen.”

Modular builders are also more cost effectively incorporating elements of sustainable design into new construction. The 1800 Terry Building, for example, will include a greywater recycling system and incorporate a vacuum tube for providing roughly 80% of the building’s hot water from solar energy, all at a development cost expected to be 5% lower than similar products without advanced green infrastructure.

For interiors, prefabricated building components literally are modular, as they can be customized to an owner’s needs even as the floor plan changes. “Not only is the prefab solution much faster, but it’s a method where we are striving to build better, reduce waste, use better materials and create construction that is sustainable, as the components can be reused," Loberg said. "It’s very much a Lego system.”

Still nascent, modular construction is expected to gain traction as projects prove out the promised cost and process efficiencies. Both Full Stack and CollinsWoerman are pursuing just a handful of projects using such systems into 2017.
Southland's Miller characterizes modular as an emerging technology rather than the latest high-growth industry up-and-comer.

“We’re getting better at maximizing simplistic builds and beating the market,” he said. “Not every investor is progressive and willing to play around with modular, but if you are a repetitive owner, or have built a business around innovation, I can’t think of a better way to go.”

Original link - Construction Dive


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