For the past seven years, Hong Kong has held the title of the world's priciest city for home-buyers, according to the 2017 Demographia International Housing Affordability Survey.

James Law, a Hong Kong-based architect, believes that his micro-homes could help alleviate the city's housing crisis. But his tiny home designs are anything but typical — they are concrete water pipes outfitted with all the amenities of a modern home.

Law explains more about his "tube home" design below.

Called the OPod, the "tube homes" measure 100 square feet. For perspective, a standard one-car garage is about 200 square feet.

Image: James Law Cybertecture

Law's firm, James Law Cybertecture, manufactured the tube home pictured below from a water pipe with a diameter of 8.2 feet.

Image: James Law Cybertecture

It includes a sofa that folds out into a bed, as well as shelves, a mini-fridge, a microwave, and a bathroom with a shower.

Image: James Law Cybertecture

Right now, the home design is only a prototype. But Law said he planned to start selling the homes soon — his team is seeking permits from the city to start building.

Each tube home will cost $15,000. That's not cheap, but it's much less than the average price of a new home in Hong Kong: $1.8 million for a 600-square-foot unit, according to one estimate.

Image: Financial Times

Law sees his tube homes as one temporary solution to Hong Kong's housing shortage. The pods could stack in unused urban space, like shipyards ...

Image: James Law Cybertecture

... between buildings ...

Image: James Law Cybertecture

... or even under highways.

Since the pipes weigh nearly 22 tons, they don't need bolts to stay together when stacked. Law said that would keep installation costs low.

Image: James Law Cybertecture

"In Hong Kong, many people live in squalid conditions or in partition dwellings, as there are extremely high rents, housing costs, and inadequate public housing," he said. "The OPod is an inexpensive alternative."