When Helen Zhou began looking for an apartment to buy in London, she already liked the thought of living small.

“I’m into the idea of minimal living, and a strict follower of Marie Kondo,” said Ms. Zhou, 33, a software engineer. She was also concerned about the environment and knew that living in a small space was one way to reduce her carbon footprint.

As it happened, those desires dovetailed nicely with her budget. “I wanted a flat that was quite central,” she said, with south-facing windows for light. “What I could afford was just a small studio.”

In November 2020, she closed on her new home: a 312-square-foot apartment that she bought for 328,000 British pounds (about $420,000).

It had a recently renovated kitchen and bathroom — they were good enough to keep, she thought — and a living area roughly the size of a single bedroom. But Ms. Zhou had seen enough inventive apartments online to know that, with a little design help, that small room could be more than just a place to sleep.

Still, she moved in without changing anything. “I wanted to live in the space for at least a year, just to get a feel for it,” she said, shifting her furniture around to see what felt best.

Soon after, she began looking for an architect, and got in touch with Sara L’Espérance and Michael Putman, the partners of the firm Suprblk, after seeing a small, multifunctional apartment in London they had designed for themselves.

It turned out that Ms. L’Espérance and Mr. Putman had since moved to Halifax, Canada. But they had become adept at working remotely during the pandemic and were keen to collaborate with Ms. Zhou.

To start, the architects asked what she wanted from the space, instructing her not to hold back. “I had quite a lot of requirements,” Ms. Zhou said.

In addition to spaces for cooking, eating and sleeping, she said, “I wanted a lounge; I wanted to entertain people; I wanted a place to play board games. It was quite a long list.”

Cramming so much into that tiny apartment might have seemed impossible to others, but Ms. L’Espérance and Mr. Putman relished the challenge. “The question was how to achieve all these different areas without making the space feel closed in,” Ms. L’Espérance said. “How could we create rooms within a room, without actually using partitions or dividers?”

The answer, they decided, was to design a shape-shifting bank of custom cabinetry. After many conversations with Ms. Zhou, they arrived at a design with numerous reconfigurable components.

A full-size bed is positioned against one wall with an integrated bedside table, on a platform with storage drawers underneath. A slide-out sofa parks against the bed, offering a place to sit. Storage boxes tucked into the bottom of the sofa can be pulled out to create a larger flat surface, and the seat cushion unfolds to double in size, providing a bed for overnight guests.

When the sofa is rotated away from the bed, a table unfolds from its back to create a surface for playing games or serving dinner. In this configuration, the sofa’s storage boxes are topped with smaller cushions — and voilà, seating!

“Everything had to have two or three functions,” Mr. Putman said.

A separate desk folds out of the wall to provide a place for Ms. Zhou to work from home.

There wasn’t room for a full-size closet by the front door, so Suprblk built an open wardrobe with a hanging rod for coats and a closed cabinet lined with shelves for shoes and other clothing.

“In small flats, storage is really important,” Ms. L’Espérance said. “So every little place we could put something was utilized.”

All of the components are built from a green wood-fiber material called Valchromat. Ms. Zhou found a matching paint color and painted the wood floors, walls and ceiling in the area where they would be installed herself, creating the appearance of a room within a room.

Another benefit of using custom cabinetry to delineate spaces — rather than wood studs and drywall — was that the components could be prefabricated off site and installed quickly, so Ms. Zhou had to be out of the apartment for only a short time. The work began in February 2023 and the apartment was completely finished two months later, at a cost of less than 25,000 British pounds (or $32,000). The compact design won an award this year.

Now Ms. Zhou can hardly believe how large she can live in a small space.

“I thought I would have to make some sacrifices, but all the things I really wanted were incorporated in the design,” she said. “It’s a stunning place to live.”

Living Small is a biweekly column exploring what it takes to lead a simpler, more sustainable or more compact life.

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