This story is from Living in a Box, an episode of Business Daily on BBC World Service. It was presented by Manuela Saragosa. To listen to more episodes of Business Daily please click here. Adapted by Sarah Keating.

There are a lot of people in Hong Kong – 7.4 million to be more specific, all in an area that’s 1,098 sq km (424 sq mi). Alongside a dense population, prices have soared at breakneck speed, leaving many unable to afford the dizzy heights of property prices.

That’s why a local architect wants to turn giant concrete water pipes into mini-flats, stacking them atop each other in vacant lots. It looks like a construction site from afar – but it might be an ingenious solution to Hong Kong’s housing problem.

It’s an issue that’s needed a solution for a while now.