SINGAPORE – Apartments from the 1980s often come with quirks rarely found in newer developments: generous floor areas, stepped levels and layouts with character.

For Mr Kelvin Teo of Space Sense Studio, stepping into this Jalan Rajah condominium unit was unforgettable. “I was mesmerised by the unique layout,” says the founder of the home-grown design firm.

At over 2,100 sq ft, the three-bedroom apartment, which has since been sold by the owner who had it renovated, offered plenty of scope for reconfiguration. With a $230,000 budget and a timeline of about three months, the brief was to transform it into a dual-key unit with income potential.

The reconfiguration created space for a self-sufficient studio as well as a reorganised main unit, with new zones for cooking, working and entertaining. Along the way, design flourishes such as bold lighting features and a streamlined monochrome palette turned functional changes into defining statements, setting the tone for the rest of the home.

At the heart of the reconfigured layout is the dry kitchen, centred on an island framed by sleek cabinetry and dark counters. It...