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Best Light Palette
- Interior Designer: Khai Toh (SIDS ID1.)
- Address: 430 Ang Mo Kio Ave 3 #24-2598, Singapore 560430
- Contact: 9012-9492
- Website: www.ktarch.io
- Type of home: Inter-terrace
- Size of home: 4,245 sq ft
A naturally bright home with good airflow, minimalistic contemporary interiors.
The Brief
Faced with a strict 12-month deadline, the homeowners sought a complete transformation that would allow them to move in and enjoy their new home before their daughter left for university. The family desired a naturally bright home with good airflow, minimalistic contemporary interiors, and an outdoor area suited for entertaining. To meet the short turnaround and manage costs, they opted for a major A&A rather than a total rebuild.
“The idea is to build on the existing structure of the original house with additional structural support,” explains designer Khai Toh, founder of KTARCH. “The existing house had very limited natural lighting.”
Responding to both brief and site, Khai distilled the design around his guiding principle: People, Culture, and Place—crafting a home that connects generations, celebrates kinship, and draws its quiet strength from the character of its site.
A skylight choreographs shifting light patterns.
Sculpting with Light
Inter-terrace homes often suffer from dim, enclosed middle floors. Khai approached this limitation as a design opportunity, terracing the building mass to follow the slope of the land and opening it to light from the front, rear, and roof. “Light has been the protagonist in this project—it brightens every corner through layered spaces to enliven lives within, truly transforming a dingy past,” he says.
A skylight crowns the stairwell, channelling in daylight through open-riser treads, while glass balustrades and pale surfaces allow it to cascade between levels. “We designed open risers for lights to reach deeper into the lower floor from the skylight at the roof,” Khai explains. Oculus, clerestory, and ribbon windows further choreograph shifting light patterns, bringing a quiet dynamism to the interiors as the day unfolds.
Sunlight floods the stairwell.
The Upper Room
The home’s luminous journey culminates in a soaring, double-volume room on the top floor---Khai’s favourite spot. “My favourite space is the third-level double-volume multi-purpose room—a celebratory space that is unique, light-filled, and adaptable,” he shares. Concealed within the timber panelling is a Murphy bed and storage, allowing the room to flex between guest suite and family retreat.
“By day, sunlight floods through clerestory glazing and the oculus above. By night, soft illumination restores calm, and the oculus permits star gazing while you’re lying on the bed.” This tranquil volume captures the spirit of the home—serene, generous, and open to the sky.
A light-filled study.
Time and Craft
Completing a project of this scale and complexity within ten months called for both precision and presence. Khai recalls how close coordination between the design and construction teams was key to maintaining momentum and keeping the design intent intact from start to finish. “Being present on site allows for timely dialogue, informed decisions, and the safeguarding of both craft and concept throughout the build process,” he explains.
“My approach to design is grounded in my Chicago training, guided by the principle that form follows function,” Khai adds. “Good architecture and interior should be able to honestly express their purpose without unnecessary ornamentation.”
That dedication to purpose shaped every decision—from the alignment of light and structure to the refinement of stair edges and material transitions. Each gesture was measured, each surface deliberate, culminating in a home defined by composure and a deep mastery of craft.
An oculus allowing passage of space and light.
The Appeal
Architecture of Light reveals how thoughtful design can turn constraint into possibility. Within the limits of an inter-terrace, Khai Hoo Toh draws light deep into the home, transforming a challenging typology into a serene, enduring expression of how architecture can both shelter and uplift.
KTARCH is a boutique architecture and interior design studio led by Chicago-licensed architect Khai Toh (pictured).
KTARCH
Founded in 2023, KTARCH is a boutique architecture and interior design studio led by Chicago-licensed architect Khai Toh. With more than three decades of global experience—including 25 years in the United States and the past decade in Singapore—Khai’s work spans multiple scales, from interiors and architecture to urban design.
Educated in the Bauhaus tradition, he holds a Bachelor of Arts degree in Interior Design from the Harrington Institute of Interior Design in Chicago, and a Master of Architecture and Urban Planning from the University of Wisconsin–Milwaukee.
Khai is a member of the American Institute of Architects (AIA), and licensed under the National Council of Architectural Registration Boards (NCARB) in the US. He is also a LEED Accredited Professional (LEED AP), bringing deep expertise in sustainability and green building strategies to his practice.
Khai’s international career covers workplace interior, retail, residential and commercial projects, as well as healthcare and research laboratory facilities. He has been involved in urban redevelopment projects in Southeast Asia, global corporate headquarters for Fortune 500 companies as well as the restoration of 15th-century monastic relics in Bhutan. Khai’s work has received recognition from the American Institute of Architects and the American Society of Interior Designers.
At KTARCH, Khai views design as a conversation between people, culture, and place. Every project begins by listening: understanding the uniqueness of each client, lifestyle, and the calling of the site. For him, meaningful design uplifts the human spirit and enriches life. As he puts it, “we aspire to create a poem out of each project, allowing the voice, caesura and rhythms of our conversations to shape the form.”