With codes pushing electrification, builders and designers may be under the impression that fuel no longer has a place in the energy equation. However, dual-fuel houses featuring both propane and electric power are challenging that notion, helping builders achieve net-zero goals while offering options buyers desire.

Mandates such as the 2022 California Building Standards Code specify that new homes be “electric-ready,” but that doesn’t necessarily mean all electric, explains Hans Anderle, principal of Bassenian|Lagoni, an architecture and planning firm in Newport Beach, Calif. Rather, a new house must be prewired to accommodate an electric heat pump water heater, EV charging, battery storage, and solar panels. That still leaves the door open for high-performance gas appliances, with the caveat that builders offset those emissions with additional efficiency measures and meet ventilation requirements.

This is how designers at Bassenian|Lagoni create plans for production builders that comply with new energy codes and accommodate amenities that appeal to different buyer profiles. Flexible designs within an electric-ready context allow builders to offer upgraded appliance packages, including propane ranges, water heaters, fireplaces, and outdoor kitchens.

“That flexibility is really important in today’s market,” says Katie Yost, Bassenian|Lagoni associate senior designer.

Photo courtesy of Zonda Home
Photo courtesy of Zonda Home

Best of Both Worlds

To get a sense of how a single-family home can be ready for the clean-energy future while offering the convenience and comfort of gas systems, look no further than the 2024 Virtual Concept Home by Livabl. The project is a collaborative effort between leading homebuilders, architects, and designers. The Propane Education and Research Council is a sponsor.

Dubbed “the home that grows with you,” the Concept Home showcases the latest in sustainability and environmental efficiency, along with flexible design options catering to different buyer types, from empty nesters to multigenerational families.

“This was designed to be the home of today—not a futuristic home, but really meeting the realities of what a homebuilder is looking for today,” says Yost, who participated in the project.

To tour the virtual home is to see a perfect union of propane and electricity, starting in the garage. The single-car garage is oversized to accommodate an EV charger, battery storage, and a propane-fired tankless water heater. The backyard, meanwhile, is an outdoor oasis with a propane grill, firepit, and a heated 20-foot pool. The pool is one example of why gas is still needed: It’s more efficient to heat a pool with propane or natural gas than with electricity.

The Concept Home is the culmination of best practices that satisfy both code requirements and buyer expectations, Anderle says.

Energy Security

While the Concept Home is just that—a concept—a real-world example of fuel duality can be found in Arizona’s high-alpine country.

Bill Owens is the president of Worthington, Ohio-based Owens Construction, specializing in custom home and remodels, and the third vice chair of the board of the National Association of Home Builders. Renovating his mountain A-frame in the Flagstaff, Ariz. area presented an opportunity to combine electric heating and cooling with propane-powered redundancies.

The high-altitude region is prone to extreme temperatures, including heavy snowfall and monsoonal conditions, so Owens placed a premium on comfort. He upgraded the insulation and created a tight envelope with fire-resistant materials to shield from wind penetration. Electric mini-splits maintain indoor comfort until temperatures plunge into the negatives or the power cuts out. That’s when the propane-fueled standby generator powers up a back-up gas furnace.

“Being literally at the end of the grid, it was an easy decision,” Owens says of installing the secondary heat source.

Owens’ project, which is zero-ready, also demonstrates the need for backup power during a time when blackouts are becoming more frequent due to extreme weather and increased strain on the grid.

“It really can’t be a single fuel source in many situations,” Owens says. “I think my house is a perfect example of that.”

For more, see the new ARCHITECT Studio Session, Dual-Fuel Energy Systems: Best Practices and Code Considerations.