Two decades ago, Ed Ng and his partner Terence Ngan first visited the Japanese alpine town of Karuizawa as Hong Kong-based city dwellers seeking a peaceful weekend escape. Today, the co-founders of international design and architecture studio AB Concept have made this mountain retreat their permanent home, creating a unique residential compound called Itsu Sho Sha that seamlessly blends architecture with the natural landscape.
Located 1,000 meters above sea level and just an hour from Tokyo via the Shinkansen bullet train, Karuizawa has earned its reputation as Japan's version of the Hamptons. The town offers cooler temperatures than the bustling capital and showcases four distinct seasons, from blanket snow in winter to bursts of cherry blossoms in spring. This natural beauty has long attracted creative minds, most notably John Lennon and Yoko Ono, who spent several summers at Ono's family home in the area.
Ng and Ngan's romance with Karuizawa began during their stay at the newly opened Hoshinoya resort, the Japanese hospitality brand that helped put the town on the international map. "It was November and freezing," Ng recalls of that first visit. "But it was beautiful. It felt like another world." The contrast between their urban Hong Kong lifestyle and the tranquil mountain setting proved intoxicating, transforming their monthly visits into fortnightly pilgrimages.
By 2017, the couple had purchased their first property in Karuizawa – a modest two-story, three-bedroom timber cottage nestled into a hillside slope. "It was great, but because we often had friends to visit, we started to feel we needed more space," Ng explains. The opportunity for expansion came a year later when a neighboring plot of land, three times the size of their home's footprint, became available.
Having become intimately familiar with the town's natural rhythms, the couple felt ready for a more ambitious project. "We got to know the neighborhood, the landscape, how the weather changes," says Ng. "So when we bought the land, we pretty much knew what we wanted to do." Rather than constructing one grand mansion, they conceived something more akin to a hamlet – four smaller, interconnected buildings arranged along the slope, each serving a distinct purpose.
"I didn't want to build a huge mansion that didn't fit in with the landscape," Ng explains. Their original cottage would be converted into a guesthouse, while a newly constructed main residence would serve as the heart of their mountain life. Additional structures include a building housing a gym and garage – essential for the area's heavy snowfalls – and a sizeable greenhouse to provide year-round foliage and gardening space.
The entire compound sits at the foot of Mount Asama, one of Japan's most active volcanoes, a geological factor that required careful consideration alongside the country's earthquake-prone nature. To address these engineering challenges, the couple enlisted renowned architect Kengo Kuma to guide the structural design and ensure masterful engineering throughout the project.
Despite their design studio's collaborations with some of the world's most luxurious hotel brands, including Four Seasons, Mandarin Oriental, and Ritz Carlton, Ng and Ngan chose an understated approach for their personal residence. "We didn't want anything elaborate," says Ng. "The real star is the landscape surrounding us." The rooms remain simple but are filled with carefully curated art and furniture collected from across Asia and Europe.
The main house, constructed largely from Japanese cedar, exemplifies the simplicity at the core of the couple's design philosophy. Rather than carving away at the natural slope, they embraced the existing topography. A reinforced concrete base anchors the structure like a bridge, creating the effect of a house that appears to hover between the forest and sky. The ground level leads to an upper floor featuring the kitchen, dining area, main bedroom, and living room beneath a sloping roof that rises to five meters in height.
"By keeping the existing contour line of the slope, we're able to enjoy an unobscured view of the forest," Ng notes. The living room features floor-to-ceiling windows and is anchored by bold focal points, including a vintage Preciosa chandelier from a 1970s Prague hotel and a bespoke fireplace crafted by a local ironsmith. These statement pieces are combined with carefully selected furniture from renowned designers Hans Wegner and Edward Wormley.
While the architecture reflects Japanese restraint and minimalism, the interiors reveal three decades of passionate collecting. Since partnering 30 years ago, Ng and Ngan have gathered furniture and art from across Asia and Europe. "We've always been very fond of furniture. It doesn't matter if it is Scandinavian mid-century or Chinese Ming," says Ng. In the guesthouse, Oriental antiques are paired with chairs and stools from Japanese-American architect George Nakashima, alongside a Gio Ponti sideboard and a Frank Lloyd Wright lamp crafted in Japanese paulownia wood.
At the center of the living space lies a hand-knotted cream Tai Ping rug designed by Ng and Ngan themselves, inspired by Ng's grandmother and her knitting skills. "I have fond memories of watching her knit," he says. "I was fascinated by how she created all the cabling without even looking. I wanted to translate that texture into a carpet." The landscape serves as a striking backdrop to many pieces of art throughout the compound, with the natural beauty complementing their carefully curated collection.
When not traveling for work – AB Concept maintains offices in Hong Kong, Taipei, and Milan, serving clients in 16 countries – Ng divides his time between his study, the living room, and the greenhouse. "The greenhouse is somewhere I love because there are no distractions, just a little music player. It's where I like to do my creative work," he explains. The space provides a peaceful sanctuary for contemplation and design inspiration.
Although the couple had initially envisioned the Karuizawa project as a retirement plan, the COVID-19 pandemic stranded them at the mountain retreat and led to a life-changing realization. "We brought our two dogs back from Hong Kong and knew it was official – this was going to be our main home," says Ng. The forced isolation revealed their deep connection to the peaceful mountain environment and slower pace of life.
The transition from Hong Kong's urban energy to Karuizawa's tranquil atmosphere has transformed their daily routines and priorities. "While Hong Kong was about the hustle and bustle, Karuizawa is the opposite. Here, you actually want to stay in, relaxing and cooking together. It's a slower pace of life," Ng continues. This lifestyle shift has introduced new passions and interests previously unexplored during their busy city years.
Gardening has emerged as an unexpected and deeply rewarding passion for both partners. The couple has planted hundreds of trees across their property, gradually transforming what was once bare soil into a lush, thriving forest ecosystem. "Watching something you have planted grow is very rewarding," Ng reflects, highlighting how their connection to the land has deepened through hands-on cultivation and stewardship of their mountain environment.
