Hong Kong, China (CNN) -- Urban dwellers worldwide dream of someday trading a studio flat for a spacious house. Hong Kong designer Gary Chang, however, has fashioned his 32-square-meter (350 square feet) apartment into a space that can transform into 20 separate rooms.
"Instead of me moving from one room to another in this space, the rooms move for me," says Chang, who spent six months on the design.
His meticulously-designed apartment features a series of sliding walls around one central space. Slide the TV forward to reveal the kitchen, including a fully stocked mini bar. Move back the CD rack, and suddenly there is a full bath. Another wall slides to reveal a closet stuffed with storage.
With a few quick steps, he can create a master bedroom, a laundry and a guest room. He can also create a home-cinema, with a built-in projector and movie screen that covers the main window.
Chang's unique design gives his apartment a spacious feel, at least by Hong Kong standards -- the city of more than 7 million is among the most densely populated in the world, and the average apartment size is just 56 square meters (600 square feet).
Chang understands well the overcrowded conditions that prevail in this city. The 47-year-old grew up in this apartment, sharing it with six others -- his parents, three younger sisters and a tenant. In those days, it was divided into three bedrooms and Chang slept in the living room, little more than a corridor.
"We had to learn the art of living close together," Chang recalls. "One thing I remember is we spoke quietly."
As the urban population grows worldwide, interest in Chang's apartment has gone global. A video on YouTube of the apartment has attracted 3.18 million viewers. "I have done quite a number of lectures, explaining my home everywhere, from New York to London, Paris," Chang says. "Afterwards, people always come up to me to say, 'Oh, my home is similar'."
But can Chang's transformer-like designs be replicated? "It can be done on a mass production scale. It can be done on a very economical and affordable basis," said Anna Kwong, the head of Hong Kong's Institute of Architects.
There are limitations though. Kwong says Chang's concept works best for a single-person home, where rooms can easily be folded away without occupants. And Chang himself struggles with one of his own central rules. Never leave anything on the floor.