We now have the evidence that proves Jane Jacobs was right – it’s time we started acting on it

A wise planning lawyer described public consultation to me the other day as “patronise and then ignore”. The same could be said of much of the design and development industry’s relationship with Jane Jacobs, the pioneering urban campaigner and author of The Death and Life of American Cities who was born on 4 May 1916.

At first, she was ridiculed. Establishment architects, planners and city leaders decried her as a “crazy”, “militant dame”, a “housewife” writing “trash”, “junk” and “bitter coffee-house rambling.” From the left she was attacked for opposing modernist “anti-city estates” or endorsing gentrification (“de-slumming” as she termed it).

Now she is lauded. Her biography is not just written but read. Every year her birthday is marked by urbanists and architects.

When asked if her work was influential, Jane Jacobs said that her judgement was “yes and no.” I would say that many planners, architects and developers love her platonically: they value her name, they drop it into their visions, strategies, frameworks and master plans, but their process and products too often miss the point.

Like the Romans’ relationship with their city goddess or our own with the late queen, we admire from afar but do not know her.

Jane Jacobs’ subject was, as she put it, “the ecology of cities”. She argued that the “kind of a problem a city is” was one of “organised complexity” and that certain organic, jumbled-up unplanned factors tended to be associated with more prosperous, busier, healthier and happier neighbourhoods.

Jane Jacobs argued that “the processes that occur in cities are not arcane, capable of being understood only by experts. They can be understood by almost anybody.”

The Death and Life of Great American Cities is predominantly a book of theory, example and anecdote. That is not a criticism. When Jacobs was writing over 60 years ago, the evidence did not exist. But now it does. And we can use it to “back test” Jane Jacobs.

Thanks to mobile phones, to QGIS software, to hedonic modelling, to the relentless march of geo-located “big data” into our lives, we can now tell a far more confident story about the probable relationships between urban morphology and movement, between design and density with human outcomes. There are hundreds of statistical studies and dozens of books. I have even written a few myself.

The data is never absolute. We are not automatons controlled by our environment. But there are clear and consistent slopes in the neighbourhood data from rich and poor, old and young, north and south.

Jacobs praised walkable neighbourhoods with a rich diversity of uses not sterile “zoning” into places to live over there and shop over there. She was right. Studies show that homes near to neighbourhood shops are worth more, that homes in more walkable neighbourhoods are worth many tens of thousands of pounds more – other factors held equal – and that shops in walkable neighbourhoods generate up to 80% more sales.

Such coherently complex neighbourhoods are also associated with more walking, better health and cleaner air. 50 out of 64 academic studies find an association between compact walkable neighbourhoods with positive health outcomes.

The rest are unclear. None find a reverse correlation. And yet we still permit drive-to “boxland” shopping zones and prevent, through Article 4 Directives, the evolution of our high streets.

Jacobs praised the street with doors and windows that faced the public highway, rather than turning in on themselves. She praised active facades. She was right. Urban blocks with “clear backs and fronts” are associated with lower crime, particularly in British and Australian studies.

In a study that Create Streets conducted of every neighbourhood in six British cities, neighbourhoods with unclear block patterns were consistently associated with higher indices of multiple deprivation. And yet prize-winning estate regenerations built in the last decade still muddle up the private and public, running back gardens into public walkways.

One final point. Jane Jacobs argued that “the processes that occur in cities are not arcane, capable of being understood only by experts. They can be understood by almost anybody.” She had a horror of the “visible ego”, “look what I made” approach to design. She was right about this too.

And this is why we have found a very consistent relationship between the places people say, in stated preference surveys, they prefer and the evidence on land values and on public health and wellbeing. One planner said on a teams call a few weeks ago “how do we overcome the prejudices of the public… they need to be helped.” Bunkum.

So to end at the beginning, this is why it matters that Jane Jacobs’ work so imperfectly influences the world we are creating and stewarding today. And why, if we wish truly to celebrate Jane Jacobs, we should stop creating what she termed “anticity” projects, start restitching our cities, tame the dual carriageways, stop dumping drive-to cul-de-sacs into fields, and create not towers in the park but beautiful, walkable and varied streets and squares, plots and blocks.

Because ultimately, we are all humans. And we all need our home, our place, our neighbourhood as we make our brief way through the world.