Small mercies? Welcome to Tokyo's micro-flats, the last word in bijou living

It is one of the quickest viewings in estate agency history. As soon as the door opens, every inch of living space except the sleeping quarters is visible.

- Justin McCurry

A tiny genkan entryway, which could nearly accommodate three pairs of shoes, leads to a shower cubicle on the right with just enough room to swing a sponge, next to a toilet that - door left open - one could occupy while just about rustling up dinner in a kitchenette 50cm away on the other side of the "corridor".

The Guardian spent the night in Shanti Casa, in the Yotsuya district of Tokyo, the architectural answer to growing demand among young people who are unable to afford the capital's high, and rising, rents.

Each micro-apartment measures nine square metres - just under half the size of a typical studio apartment in Tokyo - their cosy proportions offset by white walls, a large window at the back, and a 3.6-metre-high ceiling. The block is among 100 buildings opened in Tokyo by the real estate developer Spilytus in the past seven years.

Rents for micro-apartments can be as low as ¥50,000 (£310) a month, rising to ¥80,000 in more fashionable locations. At Shanti Casa the monthly rent is around ¥70,000 - that's ¥20,000 to ¥30,000 lower than the average for the area.

Critics say the boom in micro-apartments highlights the lack of affordable urban housing for young, underpaid workers, with quality of life sacrificed for convenience and affordability. But Keisuke Nakama, the firm's president, says the idea is to give tenants financial breathing room while they consider their long-term futures.