Thursday, January 16, 2025
Offsite Construction Career Center
HomeInnovationHow Architects Adjust to Modular

How Architects Adjust to Modular

Advice on how to design for off-site volumetric construction

by Zena Ryder

What is the difference between designing for modular and designing for conventional construction? How much of a shift in thinking does it require? To find out, we talked with two architects who have worked on conventional and modular multifamily projects.

Sara-Ann Logan is the Vice President of Design at Volumetric Building Companies (VBC), which has its main corporate office in Philadelphia and its main design office in Boston. Kendra Halliwell is an Associate Principal and the Practice & Design Team Leader at Boston-based ICON Architecture.

Modular Design Misconceptions

Halliwell designed The Graphic, a 171-unit apartment building in Boston’s trendy Charlestown neighborhood. It’s the largest ever modular construction development in the city and ICON’s first modular project. The firm is currently working on two more modular projects. 

Halliwell says a common misconception about modular design is that it’s limited to rectangular boxes. It’s actually a lot more versatile.

Although it’s good to keep things as simple as possible to reap greater efficiency, modular factories aren’t limited when it comes to shape. “Sites in the city are often tight, and are rarely a nice square or rectangle,” Halliwell says. “To make the most of the buildable land, we incorporated some odd shapes into the project. Fortunately, the factory we worked with was willing to manufacture those.” 

Of course, the size of those were limited by roadway restrictions and available working area on the factory floor. “In this case, the boxes could be up to 68 feet long, 10 foot 6 inches high, and up to 16 feet wide,” says Halliwell. 

The Modular Design Process

For modular construction, it’s essential that the entire design process be completed before construction begins. “Traditionally, architects are taught progressive design,” Logan explains. “You start with an overarching concept, then you move into schematic design. Then you progress to the design development phase, then the construction documentation phase, figuring out more details and making changes as you go along.” 

On a conventional project, typical preliminary design is about concept: there’s no need to know all the restrictions or anticipate the revisions that may be needed later in the process. “Restrictions due to budget, exact code requirements, and so on, are worked out at each successive design step. Each step adds specificity and prompts design changes,” she says.

On a conventional project, the architect stays involved after construction begins. The contractor confirms the dimensions of the as-built structure, and the architect makes adjustments if necessary.

It’s different with off-site fabrication. “You have to know the project constraints and the ramifications of your design decisions before you start designing,” says Logan. “There are limits inherent to the medium that have to be incorporated into the design from the beginning.”

She adds that it’s important not to make changes once the factory starts making the boxes. “You will lose efficiency and speed, and profitability will be significantly reduced.”

Modular Design Thinking

When envisioning a modular design, it’s not just about making a structure buildable in boxes. Logan says that, “For me, it’s less about thinking in block-shaped pieces and more about thinking micro and macro at the same time.”

Logan explains that, whether working on conventional or prefabricated projects, some architects tend to visualize in terms of elevation, and others lean towards thinking in terms of how occupants experience and move through the spaces within a building.

Although thinking in those ways is still relevant for modular design, there’s an additional way of thinking that the architect must be adept at.

Logan explains, “A modular designer has to be able to think at a component level and also at the level of the overall building. That’s probably the hardest thing to get used to. You need to being able to focus on the small details and to get the degree of accuracy that’s needed. But you also to really respect how everything will come together in the overall building.” 

This is especially true when it comes to MEP systems, says Halliwell. In a multi-family modular building the goal, is to make mechanical system connections in corridors to minimize work in residential units. Because of this, her design team needed to include a furred-out plumbing wall at the end of the kitchen where it wouldn’t normally be expected.

“It was good to get that feedback earlier rather than later,” Halliwell says. “Manufacturers know their processes, so if they give input early in the design process, it saves a lot of back-and-forth adjustments later.”

During the contract documentation phase, Halliwell’s coordination team — including mechanical, electrical, plumbing, and fire protection engineers as well as the owner, general contractor, and the off-site manufacturer — met three times a week.

Collaborative Modular Design Team

Both architects emphasized that collaboration between architects, engineers, contractors, manufacturers, developers — even the banks financing the projects — is essential for a successful off-site construction project. 

Decisions have to be made early, in order to coordinate and delineate which work will be done in the factory and which will be done in the field. “Early collaboration and open communication will reduce surprises,” Halliwell says. “Revisions are more difficult and costly once the boxes are built.”

Everyone on the team working on an off-site project has to be willing to do things differently from the norm in conventional construction. Because of this, a collaborative attitude is even more critical than on conventional projects.

Logan advises architects to approach a modular project with a collaborative attitude, and a willingness to listen and adjust. “Appreciate that each team member is an expert at what they do. Get their input and try to understand where they’re coming from. Give your input and share where you’re coming from. With that mutual understanding, it’s easier to create a framework for doing things differently from how they’re typically done.”

As with conventional construction, it’s good to work with consistent teams or partnerships, so you’re repeatedly collaborating with the same people. “Knowing who your engineers are going to be, which factory you’re going to be using, and so on, makes things run more smoothly,” Logan says.

Both Logan and Halliwell also emphasized the importance of 3D BIM [building information modeling] software to aid in the collaborative design process. 

“We start schematic design in Revit, or an alternative full 3D environment. Because our projects are large and the design team tends to be large, Revit coupled with the Autodesk Construction Cloud has become our standard for collaboration through the project cycle. We use it on all our projects,” Logan says. “We can integrate with various project management platforms, depending on the needs of the project and the design team.”

Halliwell agrees. “It’s essential to work in three-dimensional BIM for these projects,” she says. “We expect our mechanical engineers to use a 3D modeling program, and for the modular manufacturer to use it as well. Early in the process, the architect and engineers share a 3D model. We want to be able to share that model with the manufacturer too. We use the model to avoid system clashes that might otherwise happen.”

Modular Design Mistakes

Logan says that if an architect fails to design for modular fabrication, “most manufacturers can make it work. But it sacrifices speed and profit, and the client doesn’t get exactly what they wanted.”

A basic example of this kind of design failure is “not accounting for the double mate wall that’s inherent to volumetric modular construction. If that isn’t accounted for in the initial design, then later you must either make each unit smaller, or you have to make the building as a whole larger,” Logan says. “Those are the only two options.” 

Either one risks a dissatisfied client who comes away with a poor impression of modular construction. That’s something nobody in the industry wants.

Zena Ryder is a freelance writer, specializing in writing about construction for businesses, magazines, and websites. Find her at zenafreelancewriter.com

The Graphic is ICON’s first modular project, and the largest modular construction development in Boston, Massachusetts

VBC’s co-living development in Philadelphia, Pennsylvania

VBC’s faculty housing development in Williamstown, Massachusetts

RELATED ARTICLES

LEAVE A REPLY

Please enter your comment!
Please enter your name here

spot_img

Most Popular

ADVERTISE WITH US

Get your Media Kit to advertise in Offsite Builder Magazine, OffsiteBuilder.com and ModularHomeSource.com!

Email [email protected]
for more information!