A month ago, my frail in-laws moved into a ground floor flat two doors down from us. That weekend, the upstairs neighbours popped our two-year-old next to theirs in a bike trailer – their five-year-old pedalling alongside – and took them all to the park for a few hours so we could get on with unpacking boxes.

Some care is formal. My in-laws also have live-in carers, and my daughter goes to nursery. But much of it comes from these informal networks of neighbours, families and friends looking out for each other.

Or, at least, it should.

My family is lucky to live in an urban utopia, designed before neoliberal atomisation, securitisation and car obsession. At its best, Scotland’s tenement system – though it got a bad reputation in the 19th and early 20th centuries because of outdoor toilets and overcrowding – creates community. And communities care for each other.

As Britain is engulfed in a care crisis, we need to think about the formal end of the care economy. Care for profit is absurd. As Tom Pollard, a researcher at the New Economics Foundation, put it to me: “There are nurseries operating through shell companies upon shell companies – so much of the provision is huge companies with shadowy backers.”

But while we need genuine, well-funded public services, we also need to consider those informal ecosystems. How do we build them? In what conditions do they flourish? Some of that is social policy: how much time do we have out of work? How do we ensure women don’t carry a disproportionate burden?

An important part of the answer lies in architecture and urban planning. “If you want a neighbourhood to thrive, you need neighbours to meet each other – which means pedestrian spaces so children can play and adults can hang out,” says Phin Harper, an architecture critic and chief executive of the organisation Open City, which campaigns for more egalitarian building practices. “It sets up the framework through which a community can emerge.”

But in the UK, says Harper – England most of all – communities have been pushed in precisely the opposite direction.

“As a society, we’ve got very confused about the difference between security and safety,” Harper says. “Prisons are very secure spaces, but that doesn’t mean people within them feel safe.”

The obsession with security means that in modern estates and blocks of flats, “instead of communal spaces, you’ve often got people cut off from each other”.

Unlike in older buildings, which may have been less secure but boasted publicly accessible walkways and entrances, these new buildings actively prevent people from getting to know their neighbours. Without that, it’s hard to build the kind of informal community that allows people to look out for each other.

Since 1989, the police across the UK – through a programme called ‘secured by design’ – have worked hard to make housing estates more ‘secure’. Police will routinely show up at planning meetings to argue against access routes or places for people to gather, says Harper. In a park in Ashford in Kent, for example, “police took away benches and bushes, saying it would make the area safer because fewer people would congregate. But isn’t the park exactly where you want people to congregate?”

My experience over the last decade is that wandering around new developments in urban England increasingly feels like walking around Belfast. Barbed wire, CCTV cameras and suspicion cut our communities apart. It’s no wonder we have a care crisis.

But it’s not just securitisation. In urban areas, much of the space that would historically have allowed neighbours to meet is now given over to cars. In 1971, 52% of households in the UK had at least one car. Now, it’s 78%. There are now 33 million registered vehicles in Britain, compared to 19 million in 1980.

When communities are built around cars, space to meet is replaced with space to park. Shops and services are built for people to drive to them, meaning they don’t meet on the pavement and chat – which is largely how we get to know our neighbours.

“In London, you’re now getting developments built with no parking spaces, apart from a couple for disabled people,” says Harper. “But in the rest of the country, the idea that you have slightly fewer cars, or even cars not by your front door, is very hard. It shows how dominant the car lobby is in our architecture.”

Ultimately, we have to choose between building communities centred on care, or building communities centred on cars. Too often, we stump for the latter.

Finally, says Harper, the crisis in care for people is partly a product of a failure to care for our buildings. Often, older estates – like London’s post-war social housing or Scotland’s tenements – were built with community in mind. But those communities have been ripped apart because the buildings weren’t looked after, whether by councils or other landlords, and ended up being demolished.

“Even now we know how damaging it is, there is quite a big lobby for knocking them down and replacing them with trash,” says Harper. We’re rapidly losing “a kind of architecture which promotes communality and mutual aid”.

The starting point, Harper says, “is: stop knocking everything down”.

Three years ago, I wrote for openDemocracy about my experience of depression, the broad social factors that contribute to the mental health crisis, and how to organise against them.

Over the past three years – since we had a child, since my in-laws moved nearer us, since we became much more rooted in our local community – the misery has seeped away. It’s been replaced by a sense of fulfilment, of happiness.

As humans, caring for each other is what we do best. Along with creativity, it’s what we’ll have left once we automate everything else. But just as we need time to care – time not spent working, or stuck in traffic jams – we need space. And building spaces that foster community is essential.

We’ve got another baby due in September, and I can’t wait to introduce them to the neighbours.