Housing starts in London collapsed to just 4,170 in the year to April, according to government data, the lowest figure on record and just a quarter of the average for the last five years. Starts across the country are also sharply down. While some northern markets remain strong, it is no exaggeration to say that much of the residential development industry is in something of a crisis.

Increasing regulatory requirements, compounded by soaring materials costs, mean that in parts of the country the homes developers have traditionally produced now simply cost more to build than buyers are willing to pay.

The problem is particularly acute for sites purchased several years ago before costs rose, with one in six London sites now on hold, according to data from Molior last autumn.

Andrew Matthews, co-founder of housing architect Proctor & Matthews Architects, says his practice’s situation is shared by others in the industry “We have got projects, but they’re all on hold,” he says. “If you look at our order book, it looks very healthy, but actually most of those projects are waiting for instruction.”

With build prices set to rise further in the wake of the Iran war, the problem is only going to worsen.

In the face of this, much of the industry focus to date has been on persuading the government to cut regulations or bring back support for first-time buyers.

Meanwhile some clients and designers are not passively waiting for government to ride to the rescue, but instead trying to tackle the crisis with a more radical reassessment of what they’re building. Designers are experimenting with forms, such as terraced back-to-back housing, that haven’t been used at scale in this country for many years, in order to make high-quality, high-density homes deliverable.

Doing so means moving away from the suburban houses and high-rise flats that have predominated in recent decades, and slaying some holy cows beloved by planners, funders and developers alike. So, what options are being looked at, and how do they change the viability equation?

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