Ping Wang describes the family's living conditions as lacking "human dignity, sunshine and air". Photo provided to Shanghai Star

His busy schedule affords him little time to unwind. He works around the clock and often devotes his weekends to business trips.

"If you do the same job every day, you quickly lose your sense of freshness," says the 42-year-old designer and a post-grad at University College London.

"As you can see with the TV show, I like challenges."

He sees no end to his public service work, which he approaches with missionary-like zeal.

"If I can give one or two people hope, why not?" he says.

Tips on how to improve the living condition of small space

Shanghai is notorious for its meager housing resources. The average living space per person in the late 1970s stood at just 4.5 sq m as the population exploded. It was billed as the local government's "No. 1 headache" in the 1980s. Although the number has since risen to over 17 sq m per person, some families have slipped through the cracks.

To make small spaces look larger, Ping Wang suggests covering the bathroom wall with small mosaics or installing wood-strip flooring in an oblique direction which helps enlarge a narrow space by optical effects.

Measurements are very important before starting any renovation.

"Remember Da Vinci's Vitruvian Man?" says Wang. The drawing depicts a man in two superimposed positions with his arms and legs apart in a circle and square. “It shows that a person’s height usually equals the width of their open limbs. The circle and square represents the bottom-line space for a human to feel comfortable.”

Wang suggests people living in small spaces choose furniture based on the measurements of a person's height, like he did for Gu's family, or even better, tailor-make furniture that can be folded.

But renovating a house doesn't mean to throw everything old but turn them into something useful. Also in Gu's project, Wang kept the old ladder and made it into a bookshelf and old clothes into a colorful carpet. "The ladder connects the four people," he says. "I didn't want to throw it out because it had become a symbol of family unity."