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The tatami room in Sonia Jog and Patrick Dolan’s home in Christie Pits, Toronto, has been renovated with a heavy infusion of Japanese design.Rémi Carreiro/Remi Carreiro

Even a perfunctory online search for “Japanese bathing ritual” will immediately make clear the differences from North American bathroom etiquette. A dirty body does not enter the tub. First, it is washed under a shower or while seated using water from a bucket made from Hinoki wood. Then, one enters the tub – deep enough to sit cross-legged in – to soak, meditate and wash away the cares of the day.

After that, it’s not a bad idea to take that state of mind into one’s tatami room (tatami are mats made of woven straw) to reflect further, or perhaps take a well-deserved nap.

That, at least, was the jumping-off point of the renovation undertaken by Sonia Jog and Patrick Dolan of their Christie Pits semi-detached. “The clearest thing in our idea was: let’s call it the Japanese wing. With the divided bathroom. With some sort of deep tub. And then moving the tatami room, which was upstairs,” says Mr. Dolan.

Ms. Jog, whose mother is Japanese, had discovered some years ago that a room on the third floor was almost the right size to hold six tatami mats, so her four-person family (there is a 13-year-old and an 11-year-old) had been enjoying those therapeutic benefits already. After a conversation with neighbours and friends Joanne Lam and Eric Martin, owners of architecture and interior design firm Picnic, it was decided that any renovation would have to include a room designed specifically for the mats … right down to the millimetre.

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The imported wooden tub has a dedicated faucet and a linear drain to catch overflow. On the opposite wall is a conventional shower and a low faucet for filling a wash bucket.Rémi Carreiro/Remi Carreiro

“My wife’s grandmother’s house [that] we lived in after university, every room, like the dining room, was a tatami room,” says Mr. Dolan as our little group steps lightly onto the soft mats, now lovingly located in a custom-created room on the second floor thanks to Picnic. “This is a traditional Japanese futon. We have a couple of them, and you just [put them] on the floor.”

While the air in here seems even cleaner (perhaps that hint of straw?) than in other parts of the house, it should be noted that Mr. Dolan and Ms. Jog use the room for many things: an occasional change from their conventional bedroom; a morning yoga room; and even a sort of squash ball court for a game their kids invented.

Beside the tatami room is the divided bathroom. One room contains the toilet and double sink – the pale pink, textured porcelain tile is divine. The other room contains the imported wooden tub with a dedicated faucet and a linear drain to catch overflow. On the opposite wall is a conventional shower as well as a low faucet for filling the wash bucket.

“It’s built to order,” says Mr. Dolan about the ofuro tub by Bartok Design, which came in at close to $10,000 when all was said and done. “Generally, in Japan, they’re kind of square-ish like this. Two people can comfortably bathe in it, and it’s quite deep so you really soak all the way.”

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The kitchen features bench seating on which the children can quickly slide in and out.Rémi Carreiro/Remi Carreiro

Effortless, timeless and with soft light falling upon minimalist details, it’s a beautiful room that looks as if it has always been there. But it took a great deal of effort, says Ms. Lam, who worked in Ghana and Jordan before founding Picnic with her husband: “I had to Google a whole lot of Japanese bathing rituals, and there were a lot of diagrams of how you actually position your body in the tub.”

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The renovation, which allowed the couple’s two children to get their own rooms on the third floor, didn’t stop at the second. No, going almost whole hog, Picnic assisted the family with a falling-down front porch and an old, ramshackle addition at the back – quite common with old Toronto houses – that was transformed into a solid, insulated and handsome space (which allowed for the tatami room above). In addition, the rooms in between have all become usable, open, airy spaces with generous circulation. More Japanese design principles came into play.

“This was trying to make an entry that is more intentional, more defined, and then give an area for all the stuff you have when you enter and exit – coats, shoes, keys, hats,” Ms. Lam says with a laugh as we stand in the foyer.

The foyer is also now a genkan (the traditional Japanese entryway for a house), says Mr. Dolan: “This is the dividing line,” he says, pointing to the spot where the tile stops and the wood floor begins. “This is outdoor; you can wear your shoes to here.”

Around the corner from the foyer closet is a lovely little sitting/TV room, which opens to the large dining room. As one might suspect, walls were removed and changes in floor height were levelled to achieve this. Just before entering the reconfigured kitchen, a new powder room offers a visual exclamation point via hot pink Gucci wallpaper.

Not to be outdone by wallpaper, the kitchen announces itself with a bank of teal cabinets, complete with an espresso station, that leads to a wonderful, custom bench and informal dining table. By upholstering the backrest and not the seat, family members can “slide in pretty quickly,” says Mr. Martin. While seated here, one can consider the outside world via the new sliding door to the backyard, or a window tucked behind a set of shelves.

“It’s something I like to do when there’s a window and you try to work with it,” continues Mr. Martin. “It really works to show off whatever glassware you have … let light through without wasting the space.”

It’s safe to say there’s no wasted space in the Jog-Dolan residence 2.0. Nope, whether considering the earthy tatami room, elegant tub room, playful kitchen, or the harder-to-quantify photons now painting everything in natural light, this made-to-measure Toronto house stands as a lesson in how good design makes life better.

Editor’s note: This article has been updated to correct the age of one of the family members.