Green Builder Media

Case Study: Doug Tarry Homes

Written by Amanda Ingle | Oct 2, 2026, 6:09:33 PM

The philosophy here is simple: If it doesn’t add value, it doesn’t belong in a home’s price.

Doug Tarry has spent two decades building net zero energy homes in southwestern Ontario, and somewhere along the way he stopped selling homes on price per square foot. “There’s a need to look beyond first cost and look at value adds to the home,” says Tarry, a second-generation builder and president of St. Thomas, Ontario-based Doug Tarry Homes.

What he sells instead is what he calls “total value proposition,” a belief that a home’s real worth only shows up once you look past the first number on the price sheet and ask what a choice actually gives back over time, in comfort, in health, and in what it costs to live there. It’s less a sales pitch than a genuine conviction, and it shapes nearly every conversation he has with a buyer, Tarry notes.

That conversation has changed a lot since the pandemic. Buyers who once asked almost exclusively about price started asking something more personal. “What buyers are really asking rarely sounds like a spreadsheet question,” Tarry notes. “It sounds like, ‘is my family going to be safe, is my family going to be comfortable, are we going to have a good life here?’”

Tarry traces the shift directly back to the shared experience of being stuck inside during COVID, and of Green Builder Media’s Seven Pillars of Value Per Square Foot, he names Health and Wellness as the one with the most room still to grow.

He calls his own approach “The Two Commandments”: get the water right and get the air tightness right, before anything else gets decided. Everything downstream, from window choices to how a house breathes, follows from those two priorities first.

Tarry is candid that most builders reach straight for the flashiest feature on a spec sheet without doing the quieter work underneath that actually makes a home perform and last. Tarry’s own priorities tend to run in nearly the opposite order, starting with the things nobody sees and finishing with the things everybody asks about by name.

That same instinct shows up in how he thinks about mechanical systems. Tarry’s homes need a fraction of the heating and cooling capacity of a typical code-built house, small enough that equipment suppliers struggled to serve it properly. Rather than compromise a home’s performance to make an old system fit, Tarry started his own HVAC company. It’s a decision that says something about how far he’s willing to go to keep a philosophy intact rather than water it down to match what’s easiest to source.

Getting all of this built without pricing himself out of reach for ordinary buyers has meant treating waste itself as the enemy, not comfort or performance. Tarry has spent this past year going through what he calls “a major lean construction overhaul,” questioning every bit of wasted material, wasted time, and wasted labor on a jobsite, because in his view none of that waste ever benefits the customer. If it isn’t adding value, he doesn’t believe it belongs in the price. That discipline is part of how he keeps a high-performance home within reach of buyers who aren’t shopping in a luxury bracket at all.

That belief that good building shouldn’t be a luxury shows up most clearly in who Tarry chooses to build for. Net zero-ready construction isn’t something he reserves for his most-expensive homes. It’s the baseline on a set of below market rate tiny homes his company is finishing for the YWCA in St. Thomas, and it shapes ongoing work he does with First Nations communities on housing stock he describes, without much hesitation, as shameful in its current state.

Decarbonization is the pillar Tarry has struggled with most—not because he doesn’t believe in it, but because he refuses to sell it as a premium add-on reserved for buyers willing to pay extra for bragging rights. “If it’s going to cost $100,000 more, what’s the point? Nobody will buy it,” he says. He’d rather move the needle a little for everyone than build a showcase home for the few who can already afford to care.

Asked how the whole industry eventually makes this shift—from price per square foot to something closer to what Tarry practices—he doesn’t reference a new technology or a new certification. He points to a knowledge transfer problem, a need for builders willing to teach instead of guard what they know.

Tarry has walked competitors through his own building details and invited them into his own training sessions, on the belief that raising the whole industry matters more than protecting a competitive edge. It’s a philosophy he traces back to something older than any certification program, and a question he keeps coming back to. “Why build the hundred-year home?” he asks. “Because we must.”