The robust design of a building could be a secret weapon in the fight against vehicular attacks.

If you walk along Whitehall in London’s Westminster, it’s hard not to feel a sense of history in your surroundings. You’ll see the Foreign and Commonwealth Office with its imperial heft, the traditional Red Lion pub and some classic red phone boxes dotted along the pavement. It’s a timeless image of Britain as imagined in the minds of tourists.

As you approach the gates of 10 Downing Street, the pomp and ceremony continues. The road is lined with a long stretch of traditional stone columns and elegant traditional bollards. But these are not constructions from a bygone age. They were only installed in 2008, and are actually an ornate disguise for a series of heavy-duty, steel-reinforced security barriers designed to mitigate vehicular terrorist attacks.

The 1.1m-high bollards – known as Westminster Bollards by manufacturer ATG Access – are crash-tested to withstand an impact from a vehicle moving at 40mph, and they can be found almost everywhere in Westminster.

Such attacks are, depressingly, an increasingly common occurrence. Since the failed 2007 attempted ramming of Glasgow Airport, and the attempted bombing of Haymarket in London in the same year, Britain has faced attackers using vehicles as weapons a number of other times, such as the 2017 attacks on Westminster Bridge, London Bridge and Finsbury Park.

The idea behind the bollards is simple: to protect pedestrians and the people inside buildings and, if the vehicle does contain a bomb, to make the blast occur away from the building being protected.

“You don’t want every building to be like Fort Knox from the outside,” explains Iain Moran, ATG’s sales and marketing director, which is why these disguised bollards are an important part of making buildings secure. His company has carried out over 120 impact tests on its range of bollards – which are now used on seemingly every notable building in London, including, most recently, the new Tottenham Hotspur football stadium in the north of the city. The impact-tested steel barriers can now be found inside a wide range of different street furniture; including flagpoles, bus stops and street lighting.

Peter Jackson, the managing director of Jacksons Fencing, which sells security fencing, also highlights some of the smart architecture at the Emirates Stadium, North London home of Arsenal Football Club.

“On match day it can expect crowds of up to 65,000, all crowded in the space in front of the stadium. A vehicle attack would be disastrous,” he explains.

“However there are a number of defensive measures in place which most people are not aware of. Between the road and the pedestrianised area is a sculpture with huge letters spelling ‘ARSENAL’. These are strong enough to stop a vehicle, preventing it from reaching the crowds. In other areas the club’s heritage, large steel cannons, the club’s symbol, also greatly reduce the chance of hostile vehicles gaining access.”

So while these features may appear as though they have been designed with Instagram photos in mind, they are actually serving an important purpose. In fact, once you start looking for them, these sorts of features can be found everywhere.

Since 2006, the government and industry have developed and iterated various impact standards – so this sort of defensive thinking, and hiding the measures in plain sight, is today embedded in how buildings are designed. Over the last few years, ATG’s Moran has worked with the biggest names in the business, such as Foster & Partners and Zaha Hadid Architects, to integrate hidden barriers into their new buildings, and retrofit barriers into existing properties.

Using design to engineer security is not just for high-profile and sensitive locations. Architects are trying to ‘design out’ crime in more ordinary buildings, too.

The prize for the most dystopian motive for this almost certainly goes to Fruitport High School in Western Michigan, where a $48m (£37m) renovation and expansion will incorporate protection against mass shootings. The new layout features curved corridors and classrooms with built-in blind spots for anyone peering through the classroom door – the idea being to limit the lines of sight of a potential shooter, and to enable the class to hide out of view.

It isn’t just about stopping atrocities. Design principles are also being used to protect homes against more mundane forms of crime, such as burglary, vandalism and anti-social behaviour.

Secured By Design (SBD) is a police organisation founded in 1989 with the express goal of helping developers and local authorities ‘design out’ crime, in many cases embedding SBD police officers in planning departments across the country – so just as planners will consider the aesthetics of a proposal, or whether it will disrupt traffic, they will also be able to understand whether proposals are optimised for security.

The principles behind it are simple but effective. For example, one goal is to create as much ‘natural surveillance’ as possible, by ensuring that ‘habitable rooms’ – like living rooms and kitchens – face onto the street, so that householders will be more likely to spot any suspicious behaviour. And for this to work most effectively, it is important to ensure that front gardens are landscaped with plants that will not grow higher than a metre.

The guidance also says that cars are much better parked in a garage or directly outside a property than in a communal car park. An SBD-certified home will never have the gable (side) wall of a row of terraces facing on to a park, because of how it could encourage ball games or other anti-social behaviour.

One of the clearest rules is that SBD attempts to limit access to the rear of properties – so alleyways or shared passages leading to multiple properties are a no-no.

“The security of the rear of the home could be down to your most forgetful neighbour,” says Michael Brookes, SBD’s head of operational services. “We want to try and create an environment where you have the chance at least of being able to know or recognise your neighbour,” he adds.

Brookes believes the key principle is that of ‘defensible space’, in which space is divided into four categories. There’s fully public – the street outside, and fully private – the interior of someone’s house. The slightly trickier categories are semi-private spaces, such as interior corridors of a block of flats, where visitors are allowed, and semi-public places such as a front garden, where it would be deemed acceptable for a delivery driver to enter, but unacceptable for a member of the public to decide to have a picnic there.

Crucially, the goal is to use the design to clearly demarcate these spaces, to keep criminals away and enable residents to correctly assess when suspicious behaviour might be occurring. “When we get it right, we empower residents to control the areas around the home,” Brookes explains. “Really in crime prevention terms we’d like things to be as private as possible because we know that when we create more private space we really then are enabling residents to control the areas around the home.”

What makes SBD rigorous is that it isn’t just a specification; there is an accreditation scheme. Today, hundreds of companies ranging from glass makers to window and door fabricators and property developers are all members, and apply to have their products certified as meeting the Police Preferred Specification. So influential has this specification become, that it can be tricky to receive planning permission without it – which is why, since 1989, more than a million homes have been built that comply with the specification.

What’s more, Secured By Design appears to be getting results. The organisation claims that since it was founded, crimes on new developments have been reduced by 87 per cent, and by 61 per cent on major refurbishment projects.

So, design can be used to tackle terrorism and crime. This does not mean that these sorts of design cannot have negative consequences, too.

Some of the most frought debates around protecting us from terrorism arise because the same tools that can protect us, can also be used to control us. For example, the bulk collection of everyone’s internet browsing data will, in theory, help the authorities identify and stop terrorists – but the same tools can also conceivably be used to monitor dissidents and political activists. The same point can be made for design: it could control and modify our behaviour in ways that we may not even be aware of.

Perhaps the most famous examples of this are homelessness spikes, which first came to attention in 2014, as activists raised awareness of how some building owners were placing metal studs in doorways to make it uncomfortable for rough sleepers to sit down.

Another example is the ‘Camden Bench’, which was designed for the eponymous London borough, with contours and features that make it difficult to sleep or skateboard on – and only facilitate sitting, as intended, for brief periods.

Will Jennings, a writer and visual artist, points to the concept of a ‘synopticon’, which was developed by sociologist Thomas Mathiesen. This is the idea of pervasive surveillance – not by a handful of guards or CCTV, but by the way in which design is used to control and modify our behaviour.

“The idea we’re all watching out for each other and we’re all implicated in that policing is something which I think has entered the civic space quite strongly,” he says, arguing that the level of trust and fear caused by this monitoring has subtly shifted over time.

This critique is echoed in a report by the New Economics Foundation titled ‘Fortress Britain’, which argues that levels of crime do not correlate with the fear of crime, which depends on how much trust we have in other people, and that schemes like Secured By Design risk undermining those bonds of trust and belonging.

“It appears that we are shaping our physical environment in response to the consequences of complex social problems, and in so doing are stripping away the social resources which we depend on to live well together,” the report concludes.

In other words, defensive architecture is a sticking plaster attempting to solve much deeper problems. Is this sort of design something we should worry about? Ultimately, it perhaps depends on your historical vantage point.

Luke Bennett, a reader in ‘space, place and law’ at Sheffield Hallam University, is surprisingly relaxed about defensive architecture in public space.

“The ‘radical geographer’ complaint is that in many areas, we’re subdividing society and the rich people are hiding in their compounds behind gated community fortresses and nobody’s talking to anybody anymore because they’re all living in these chopped up, subdivided areas,” he explains. But his own view is rather different.

He points to how the built environment was much more heavily modified for security purposes during the Second World War and in the decades preceding it. “Warping of the built environment then was a much more explicit and invasive form of fortifications than what we have now,” he says. “If you think about the amount of concrete and metal that is being inserted into the built environment in the present post-9/11 era, contrast it to the amount that was inserted into the built environment in the late 1950s and into the 1960s in the name of building bypasses and separating fleshy human bodies from cars within city centres.”

In other words, structuring cities around the anxieties we have today – such as terrorism – are less invasive forms of division and control than the literal demarkation of space for vehicles in the 1960s.

Even structuring the built environment to protect against terrorism isn’t new. In the 1980s and ’90s, faced with the threat of IRA terrorism – including two successful attacks on Bishopsgate and the Baltic Exchange, the City of London financial district built a so-called ‘ring of steel’ around its perimeter. This was a series of checkpoints on every route in and out of the City, which could be manned by police and monitored around the clock by CCTV.

As part of the design of the ring, roads were redesigned, or in some cases removed entirely, in order to limit the number of entrances and exits into the Square Mile. Some of the former entry points were turned into public squares and gardens, specifically designed to prevent vehicles from passing through. Why should we worry about newer forms of defensive architecture?

In fact, Bennett argues the critics are directing their ire in the wrong places. If they are truly worried about surveillance and control, there are bigger things to worry about: our phones.

“We’ve all signed up to this idea that we know where everybody is and everything can be logged and everything can be mapped and what have you. And that’s far more of a securitisation through technology than the occasional popping up of an anti-truck barrier,” he says. “That’s a fundamental re-engineering of the way in which we live our lives.”

This isn’t to say there isn’t anything interesting about these new securitised design norms in our modern built environment. Unlike urban security features that came before, today, they come in disguise.

“I think there’s a real imperative at work that says people must see certain signs of fortification in order to feel safe in public places for fairly obvious reasons. But there’s also as part of that an ironic counter principle, which is that people mustn’t be overly scared by the fortification. They mustn’t necessarily see all of the fortification. Some of it needs to be absorbed into the welcoming tone of the streetscape.”

This is perhaps, ultimately, the tension at the heart of the disguise. In fact, as a society we may already be too good at designing security features into the built environment. So much so that, according to ATG’s Iain Moran, after the 2017 Westminster Bridge and London Bridge attacks, the disguise was judged to no longer be helpful.

“There was a bit of a shift where people wanted to just see bollards again,” he says – instead, as any visitor to the bridges will see today, there are now heavy-duty security barriers employed either side of the traffic. Grey, metal and imposing, they are designed to be highly visible, to reassure pedestrians that they are being protected. Despite the design innovations, it isn’t always most effective to hide in plain sight.