Photo courtesy of Plant Prefab

Over the last several years, prefabricated construction has been steadily gaining traction as an efficient and sustainable way to build beautiful homes. The method appealed to Steve Glenn, founder and chief executive officer of Plant Prefab in Rialto, California. Glenn founded Plant Prefab in 2016 and the company has since grown into a leading designer and builder of high-quality, healthy, sustainable and custom-built single- and multifamily homes.

“Plant was founded to make it faster and easier to build high-quality, sustainable, architectural homes,” said Glenn. “To achieve this, we designed and patented our own hybrid prefabrication methodology, the Plant Building System™, which combines the time, quality and cost advantages of modular construction with the design flexibility and expanded site access capabilities of panelized construction. Clients get an extremely durable and energy-efficient home, built to precision manufacturing standards, delivered 20-50 percent faster and with up to 30 percent less waste than traditional, site-based construction.”

The Prefabricated Approach

When most of us hear “prefabricated” or “modular construction,” we think of shipping containers. Scores of builders have capitalized on the excess of containers imported to the U.S. and then left in disuse to produce these quickly built, transportable “homes in a box.” However, there are aspects to building in a metal box (including moisture, thermal bridging, ventilation and structural issues) that inhibit sustainability goals. The shipping container method also challenges design freedom.

As a prefabricated builder specializing in custom homes and known for collaborating with a range of architects with unique styles, Plant Prefab puts design first and building method second. As a result, most of their homes end up using wood or steel framing to best accommodate the architects’ plans. With this process, tight building envelopes and high-performing materials and systems are also prioritized to keep the quality of performance on par with design.

Partnerships are Born

Plant Prefab operates a design studio in Santa Monica as well as a production plant in nearby Rialto. Each of the projects they build is personalized to its buyer’s unique needs, tastes and goals.

There’s one commonality in every home created by Plant Prefab: sustainability. Their patented Plant Building System has revolutionized prefabrication technology and helped them achieve a 30 percent reduction in waste. They also recently became the first custom prefabricated and panelized homebuilder to achieve B Corporation certification. With sustainability at top of mind, it was important to Glenn and his team to partner with architects, suppliers and other building partners who shared their values and supported their social and environmental goals. The relationship with Mitsubishi Electric is a natural fit.

“Because Plant Prefab is a certified B Corporation, we knew they’d have high standards for social and environmental performance and would prioritize fulfilling sustainability efforts,” said Ken Johnson, senior manager of performance construction, Mitsubishi Electric Trane HVAC US. “The decision to work together just highlights how much our companies’ values align, as well as our mutual commitment to investing time and resources into sustainable building.”

In 2019, Plant Prefab committed to full carbon neutrality in their operations by 2028. This goal, combined with the ever-increasing number of homeowners and builders looking to lower their carbon footprint by moving away from traditional fossil fuel-burning systems, made selecting energy-efficient, sustainable heating and air-conditioning equipment all the more important. In an increasing number of Plant Prefab’s projects, Mitsubishi Electric Zoned Comfort Solutions® offer the answer.

“We love collaborating with builders like Plant Prefab who are committed to sustainability, and helping them choose the optimal system for each of their unique and beautiful projects,” added Johnson.

Selecting the Right System

Though Plant Prefab operates out of southern California, they build homes for all climate zones. Partnering with an all-electric heating and air-conditioning manufacturer with a diverse product lineup ensures comfort, performance and efficiency for Plant Prefab homeowners, regardless of their climate zone, elevation or floorplan.

Mitsubishi Electric offers both ducted and ductless systems, all known for their performance, comfort and efficiency. A range of indoor unit options, including wall-mounted, floor-mounted, recessed ceiling cassettes, multi-position ducted air handlers and horizontal-ducted styles, allow for flexible installation and varied placement within the homes.

Because Plant Prefab homes are constructed offsite, ductless systems from Mitsubishi Electric have made on-site assembly much easier. The EZ FIT® Recessed Ceiling Cassette is popular for its easy installation, simplified maintenance and attractive design. Others homes, including Plant Prefab’s accessory dwelling units use Designer Series Wall-mounted Indoor Units for their sleek aesthetic appeal. The ideal system for each Plant Prefab home is typically determined with input from Mitsubishi Electric and insight from engineering teams who help calculate heating and cooling loads and integrate heating and air-conditioning systems with ventilation and other home systems to ensure year-round comfort.

“As a custom builder, we prefabricate homes for all climates, from desert to alpine,” explained Glenn. “The flexible design of our Plant Panels™ and Plant Modules™ allow us to custom-tailor the prefabrication of every project to its unique requirements. Plant Panel design is regionally code-driven by air, water and heat transfer analysis, coupled with local structural and seismic requirements, ensuring optimal thermal performance and durability for the specific local climate.”

With many projects in California’s mountain resort communities, cold-climate performance options are important to Plant Prefab. Their ability to expand their geographic reach hinges on the company’s ability to serve vast and diverse markets. Fortunately, Mitsubishi Electric fits the bill.

Mitsubishi Electric units equipped with Hyper-Heating INVERTER® (H2i®) technology are able to perform at 100 percent of rated heating capacity in outdoor ambient temperatures as low as 5° F, with continued operation down to -13° F. Select units from Mitsubishi Electric are also available with H2i plus™ technology, providing 100 percent performance down to -5° F. Plant Prefab homeowners can rest assured they won’t be sacrificing comfort to live sustainably.

Responding to Demand

Currently, the U.S. housing market is experiencing soaring home prices, and a significant undersupply, which Forbes estimates at 2.5 million homes. But a third trend that can’t be overlooked is the growing number of homebuyers who want healthy and sustainable homes.

Prefabricated builders are perfectly positioned to provide the solution. By condensing the build cycle and by providing energy-efficient homes, offsite construction can address the housing shortfall and attain sustainability goals. Plant Prefab homes frequently meet energy certifications such as Energy Star® and qualify for the Department of Energy’s Zero Energy Ready Home Program. In fact, they designed the first home to achieve LEED® for Homes Platinum certification and just introduced a line of Passive House standard home designs.

While prefabricated homes still represent a small piece of the market, with Plant Prefab’s sustainably built and architecturally striking designs, it’s a choice many buyers are finding increasingly attractive.