Little did they know they would help start a craze that might soon dot London with honeycomblike cubbyholes. Piercy and Conner unveiled their unique design in a trade magazine last fall, prompting a media frenzy, inquiries from financial backers and eventually more than 20,000 e-mails and phone calls from interested buyers. Now it seems everybody is talking about their Microflats and a rival firm’s Mini Suites. Both firms are in negotiations for building sites and hope to start construction by December.

The real-estate squeeze is on in London. Young urban professionals are being priced out of housing. Most banks refuse mortgages of more than three times an annual salary, and the average London salary is [Pound sterling]28,000. The same basic pressures gave birth to a similar idea in 1970s Tokyo, where cubbyhole hotels and tiny apartments known as one-room mansions are now commonplace.

The London designers say they drew inspiration from their own travails, but now plan to study Asian designs. The most famous is Tokyo’s beehivelike Nakagin Capsule Tower, which consists of scores of individual 18-square-meter living spaces, called “capsules,” that plug into two towers of concrete and steel. A product of the 1970s Metabolism movement, the Nakagin model never caught on, though the simpler mini-dwellings did. Leonard Milford, 26, an architect at Piercy Conner, says the firm may travel to Japan to take a look at the “iconic” Nakagin tower, “but we’re looking at something a little more crafted inside, which will be more than just a place to sleep.”

The Microflats will include one bedroom, a kitchen area, living area and a bathroom in about 32 square meters of space. (Japan’s one-room mansions run to about 40 square meters.) The Microflats are expected to price in at under £100,000–not peanuts, but more affordable for professionals starting out in their careers. Another company, LiveIn Quarters, has developed the Mini Suite, designed by architects John Prewer and James Wright. At 26 square meters, the Mini Suite is fully furnished with three areas: a living zone with a bed that folds into the wall and a dining table that folds into a desk, a kitchen zone and a bathroom zone. Price: [Pound sterling]65,000. Its big sister, the Home Suite, is 35 square meters for [Pound sterling]89,000.

Developers around the world have approached both London firms. The architects say that if it works in London, they’ll consider other cities. Who knows, London-style mini-flats may even wind up in Tokyo.