Rough-hewn reclaimed beams inside The Sanctuary at Hope Farms, a Net Zero Certified, carbon-negative home in Scio Township on Tuesday, June 24 2025.

ANN ARBOR, MI — West of Ann Arbor, 146 acres of land were set to be developed into 300 homes.

Instead, the property is home to 140 acres of conserved land and one carbon-negative house.

The multimillion “Sanctuary at Hope Farms" is the largest net-zero home built by Adaptive Building Owner Mike Mahon and his crew, who regularly build custom net-zero homes for clients.

The home, filled with reclaimed wood, has outside curtains, air-tight seams, geothermal heating and almost no concrete, including in the foundation.

“The first part of this was really driven by how do we honor the land and how do we honor the natural resources and environmental responsibility?” said Jeff Parness, a former venture capitalist who owns the house with his wife Sandra Hauser, a lawyer.

A custom counterweighted chandelier at The Sanctuary at Hope Farms, a Net Zero Certified, carbon-negative home in Scio Township on Tuesday, June 24 2025.

A previous owner was going to sell the property just off Scio Church Road, west of Ann Arbor, as a housing development, but his family decided they did not want to develop the land, Mahon said.

So, the family sold the land to farmer Dale Frey, who sold it to Parness and Hauser.

The couple signed an agreement to conserve all but six acres of the land and began building their dream home.

Without all of the environmentally friendly modifications, the home would have cost about $700,000 less, based on Mahon’s rough estimates. But Parness and Hauser wanted to build according to sustainable values.

Wood, wood and more wood

A custom counterweighted chandelier at The Sanctuary at Hope Farms, a Net Zero Certified, carbon-negative home in Scio Township on Tuesday, June 24 2025.

The ranch-style house’s outer walls are made of wood reclaimed from Montana barns, the inside has wood pillars from a barn in Indiana.

The foundation of the house? That’s wood, too.

The permanent wood foundation was created using pressure-treated lumber that is not prohibitively vulnerable to insects and moisture. Mahon says that the foundation will have better drainage than a common concrete foundation, and can be just as resistant to moisture as concrete. Additionally, wood is more flexible, and won’t crack under pressure from freezing like concrete can.

“The key element to successful wood foundation is really just following the steps to build it the right way,” Mahon said.

The view over the surrounding 140-acre protected woodland property from the living room of The Sanctuary at Hope Farms, a Net Zero Certified, carbon-negative home in Scio Township on Tuesday, June 24 2025.

The build team dug a little deeper than workers would for a normal concrete foundation, and then dug a 12-inch trench. That trench was filled with pea stone, which acts as a natural drain. It lets water drop down instead of building up around basement walls. They then placed the pressure-treated wooden foundation on the pea stone.

Bricks from Angelos at The Sanctuary at Hope Farms, a Net Zero Certified, carbon-negative home in Scio Township on Tuesday, June 24 2025.

To build the walls, they used strong, treated wood, and covered the outside with thick plastic sheeting to block moisture. Instead of dumping the excavated dirt back in, they backfilled with pea stone to improve drainage.

The kitchen at The Sanctuary at Hope Farms, a Net Zero Certified, carbon-negative home in Scio Township on Tuesday, June 24 2025.

“When water is coming towards the house, towards the foundation, it hits that pea stone and it just drops straight down,” Mahon said.

Much of the wood workers used for the rest of the house was sourced through relationships Parness created as founder of the New York Says Thank You foundation, created after the 9/11 attacks.

The kitchen and open-concept living room at The Sanctuary at Hope Farms, a Net Zero Certified, carbon-negative home in Scio Township on Tuesday, June 24 2025.

Boards were donated from a 1900 tobacco barn and 23 hand-hewn timbers came from an 1886 homestead. The exterior wood, from Bozeman, Montana, gives the home a Western flair that Parness wanted.

The front door features reclaimed wood artwork by Montana-based Hughes Woodworks at The Sanctuary at Hope Farms, a Net Zero Certified, carbon-negative home in Scio Township on Tuesday, June 24 2025.

“It’s that beautiful amber color that is really very unique to the West,” he said.

What was the process like?

Mahon says at the start of the design process, clients are usually given a seven-page list of questions about what they hoping to get out of each room. Parness sent back a 96-page book with help from his son, a graduate of the University of Michigan’s architecture school.

The kitchen and open-concept living room at The Sanctuary at Hope Farms, a Net Zero Certified, carbon-negative home in Scio Township on Tuesday, June 24 2025.

Parness calls himself a “cowboy from Brooklyn,” and the home reflects his nickname. He had a clear vision of a Western-style home with lots of open windows and wood. He even sourced saddles to serve as bar seats in the “party barn,” inspired by a bar in Jackson Hole, Wyoming.

The Sanctuary at Hope Farms, a Net Zero Certified, carbon-negative home in Scio Township on Tuesday, June 24 2025.

After some back and forth with modifications and suggestions, Mahon brought in all the subcontractors to make sure they were on the same page before the build started.

“The communication flow in real time between us, the architects, the builders, and their subcontractor made for this seamless, collaborative effort where everybody’s input mattered and brought together something that is so unique and with virtually no hiccups,” Parness said.

After a year and a half of building, the house turned out exactly as expected.

Walking in the front door, a cozy doorway space opens up into a wide open living area — the back wall is lined with windows overlooking the landscape. The open-concept kitchen includes a brick backsplash salvaged from from Ann Arbor’s beloved Angelo’s Diner, which closed in 2023.

On one end of the home, the spacious party barn features the saddle seats, while the other side features a garage and separate wood shop.

Triple-pane glass walls line the corridors connecting both wings to the main home. Nearly every window in the home features custom etching to prevent birds from colliding with the house.

Beyond the home’s luxury, everything was designed with the environment in mind. The curtains on the outside of the house reflect the sun’s energy, while geothermal heating in the floors, rooftop solar panels and an AI-powered electrical panel manage the flow of energy throughout the house.

A sanctuary and a generational home

Parness and Hauser have plans to share the house with the community.

For years, Parness worked in venture capital helping raise money for telecommunications companies in New York. After one of his business partners was killed on 9/11, his family started New York Says Thank You as a way for New Yorkers to give back by traveling to help rebuild after disasters around the country.

Parness helped grow the foundation to support 700,000 volunteers operating in all 50 states and 30 countries. He retired after 18 years running the nonprofit to build the Ann Arbor house.

Parness hopes the home can also serve as a sanctuary where people can heal post-trauma. It may serve as a sanctuary to 9/11 survivors or to people working for New York Says Thank You.

“Why shouldn’t they have a place like this where they could come relax and rejuvenate and get connected to nature and maybe run them through Camp David-like exercises and so forth and really, you know, cultivate new leaders and new realities?” Parness said.

Parness and Hauser will also welcome neighbors to come watch the sunset and enjoy the land.

“It’s not just a home for our family and our friends, but it’s also a place for community,” he said.