#This net-zero Hamilton home is built with straw walls

(Photography by Nicolas Koff/Office Ou)

In 2008, David and Nadine Koff—both radiologists—were living in Toronto when David got a job offer from McMaster University. To avoid a long commute, they decided to move to Hamilton, where they purchased a small two-bedroom home. Then the couple discovered the Japanese concept of “shinrin-yoku,” or forest bathing, which is the practice of nature immersion. They read studies reporting certain health benefits, including boosted immune systems and lower blood pressure, so they started looking for a new home more integrated with its surroundings.
In May of 2012, three hours before the Koffs were supposed to fly out for vacation, their realtor called about a house with a backyard adjacent to the Dundas Valley conservation area, which was carved out by glaciers 10,000 years ago. David was at Hamilton General Hospital when he heard, and he rushed over. The couple fell in love with the property’s forest-facing backyard and ample garden space, and they immediately sent in an offer. They spent the entire six-hour flight worrying about their bid and found out it was accepted right after they landed.
The home on the property was a split-level red-brick bungalow from the 1950s that didn’t suit the couple’s contemporary sensibilities. “The only thing we liked was the swimming pool,” says David. The Koffs admire Japanese and Nordic minimalism and wanted a simple, sparing home filled with lots of light, so they approached a familiar architect about designing their dream home: their son, Nicolas Koff. David and Nadine agreed that the house needed to be accessible (to accommodate Nadine’s knee issues), sustainable and feel at one with the nearby conservation area as much as possible.
They settled on a cube-shaped build with floor-to-ceiling windows that look out to the backyard. “When we get up in the morning, open the curtains and see the trees, we really feel like we are in the forest,” says David. Their home, nicknamed the K-House, is the first net-zero straw house in Hamilton. The walls are made of thick prefabricated straw-bale—a popular insulation technique in Europe. Growing up in Paris, David always saw straw underneath building floors to keep in the heat, and the Koffs liked the idea of reusing an agricultural byproduct that they could source from local farms, as opposed to importing in a different material.
There are solar panels on the roof that generate electricity, which is sold back to the grid. In the winter, the Koffs pay approximately $50 per month for utilities, and in the summer, the panels can generate up to $150 worth of electricity each month. They also have a green roof, where they have planted a pollinator garden filled with wild native plants and flowers, like black-eyed Susan, foxglove and Canada wild rye, that require zero maintenance.
The rooms inside are divided into two sections. The kitchen, living room, dining room, basement and second-floor guest suites are part of the white block, and its colour reflects heat to keep the living area cooler. The black block has the master bedroom, garage and utility room, and its colour absorbs heat, adding natural warmth to the bedroom. “The light inside is pretty magical,” says David. Multiple skylights are scattered across the home, including the atrium and primary bathroom. “It’s so calming and wonderful here,” Nadine says. The spartan interior design, which focuses on clean lines and zero clutter, helps the couple de-stress. “We never need to go on vacation.”
They hope that the home’s sustainable design will be an example for those who want to build more eco-friendly structures. “We take the world for granted,” says David. “This is our small contribution to try to make this planet a better place to live.”