A Pittsburgh Couple Build Their Personalized, High-Performance Home
Last Updated: Mar 20, 2025As a founder of TruTechTools, Bill Spohn sells quality-testing instruments for HVAC and home performance to contractors, as well as indoor-air-quality products to consumers. Spohn and his team also educate people on how to properly use those tools and products through webinars and conferences "to succeed in fulfilling the company's vision," he adds, which is that everyone can "live and work in comfortable, healthy, and energy-efficient homes and buildings."
Table of Contents
- Why Modular?
- A Personalized, High-Performance Home
- Building a Forever Home
So, it was only a matter of time before Spohn and his wife Marilyn decided to "walk the talk" and build their own sustainable forever home. As children of Depression-era parents, they grew up with an understanding of economic hardship. They learned how to work hard and save. They were also reminded to respect and wisely use the earth's natural resources. By the time he left college, Spohn knew he'd be working in an energy-related profession.
In 2019, the couple began planning their new 4,480-square-foot home on three acres just outside of Pittsburgh. In November 2020, they moved into their solar-powered, net-zero, modular home. Spohn writes about the design and construction processes on his blog, Spohn Home, to encourage like-minded folks to follow into his journey. The blog posts, he writes, intend to provide readers with insights and inspiration for making the changes necessary to combat climate change as we continue to build and operate homes.
Why Modular?
Prefabricated modular houses are built in a factory, then delivered to the building site for assembly. The factory-built modules can be end-to-end, side-by-side, stacked, or any combination based on the design. The modules are tied together with inter-connections that keep the sections in place.
"Modular was immediately appealing because it's factory-made, and all of the materials are inside and protected during construction, which is great for future durability," Spohn says. He also liked that the same crew worked on the modules every day, that the process is efficient with minimal waste, and includes ongoing quality control. Using laser alignment to keep things square for easy assembly, Spohn adds, the crew worked on the modules "from all six sides, from inside and out, and underneath and on top," for rapid, thorough, and well-integrated construction.
The four boxes are each 14 feet wide, 11 feet tall, and 64 feet long. From the interior to the exterior, the high-performance wall construction includes drywall, 2x6 stud on 24-inch centers, and R-19 fiberglass insulation. Next came a ZipSystem® air-sealed sheathing system applied to the framing, with putty put over every fastener head for air sealing and for moisture resistance. A 1.5-inch layer of graphite-impregnated EPS rigid board followed, with tape and sealant at the seams to cover all the gaps for airtightness. Next was a weather-resistant barrier, and finally an upper-grade vinyl siding as the cladding.
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Camille LeFevre
Camille LeFevre is an architecture and design writer based in the Twin Cities.