For those that work outside of the offsite construction industry, it’s confusing enough just to understand the building systems that already exist. And when a builder adopts one of the systems, they typically remain a “purist” —that is, they use that building system to the exclusion of all others. However, that isn’t exactly the smartest way to leverage the advantages of offsite construction.
What if you took two great building systems and combined them to get the maximum benefit of both of their strengths? And, what if this also reduced complexities in the field?
Structural Insulated Panels, or SIPs, consist of an insulating foam core sandwiched between two structural facings. These facings are typically oriented strand boards (OSB), but many other structural facings can be used. SIPs are manufactured under factory-controlled conditions and can be designed and fabricated to fit nearly any building design. As a building system, SIPs panels are extremely strong and energy-efficient.
Volumetric modular construction divides a home plan into modules and then manufactures those modules in a factory. They arrive at the site 65% to 85% complete, including plumbing, drywall, electric, cabinets, tile, showers, countertops, trim, etc. The balance of work is then completed in the field.
So, why is it so encouraging that these two great systems are teaming up? SIPs panels, while super energy efficient and flexible, typically replace the framing of the house only. All of the mechanical, electrical and finish work still has to be done on-site. You end up with a super strong and super energy-efficient home, but it still takes a lot of time to finish. And, if local trades are unfamiliar with SIPs panels, the installation of plumbing and electricity can be a struggle.
Using offsite volumetric modular construction takes the finish to a more complete level. And, because more of the trade work is done in the factory by workers that do the same thing every day, they are very good at it.
While volumetric modular construction is very energy efficient, SIPs can make them better. Building modules from SIPs in the factory takes strength and energy efficiency to a whole new level. Each module is almost like a Yeti® cooler.
So why aren’t more companies using SIPs panels to build their modules? Some say it’s about customer perception, but in my experience, the customer doesn’t care. I regularly ask customers if they know what is behind their walls. The vast majority have no idea. They only care that it is energy efficient and that the drywall is smooth.
Then there’s the matter of cost. Can a modular factory produce a SIPs home at a value that makes its final cost comparable to a wood-framed modular? Several niche factories and startups are already doing it, including the two profiled in this issue. Other factories are doing some pilot projects.
Let’s see what the future holds for these two great building systems.
