How can we build skyscrapers without throwing cities into shadow?

The two concept towers (semi-transparent happy couple not included). Image: NBBJ.

There are around 250 tall towers currently planned for London's skyline. From afar, they'll probably look great. But unless they're planned carefully, they'll start throwing shadows across ever-growing swathes of London.


So one local architecture firm is offering a solution. Using computer modelling, they've figured out a design which would reduce the shadows cast by two theoretical towers by as much as 60 per cent.

The architects, from NBBJ, used computer modelling to position two curved towers in such a way that, when one blocks the sun from the public plaza below, the other reflects light back down.

Oh, and before you ask, this wouldn't be a Walke-Talkie death ray situation: the towers' shape would ensure that the sunlight doesn't focus on a single point and fry anything.

We spoke to the towers' design director, Christian Coop, who says the idea grew out of a recognition that cities will need greater density in coming years – but that it'd be great if they didn't have to sacrifice daylight at ground level to achieve it. "The key to getting tall buildings right is at the skyline level and the base," he says. The design ensures that the area between the towers is bright and pleasant, so is more likely to be used as a public space:

These diagrams show roughly how it would work: 

Factoring cosmological factors (i.e. the sun) into building design is relatively new, and so to drive the point home, NBBJ placed their concept designs in Greenwich, near the Prime Meridian. Coop says he feels the "cosmological dimension" should be a routine consideration for architects, just as sustainability or aesthetics are. 

So far the concept is still just, well, a concept, but Coop hopes that architects will use this type of modelling to see how their designs will affect the light levels around their buildings. He says the method could also be adapted to control how much sunlight is reflected at different times of year: in cities like Dubai, the design could allow less sunlight to be reflected in the hot summer months, and more in winter. 

Images: NBBJ.

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Businesses need less office and retail space than ever. So what does this mean for cities?

Boarded up shops in Quebec City. Image: Getty.

As policymakers develop scenarios for Brexit, researchers speculate about its impact on knowledge-intensive business services. There is some suggestion that higher performing cities and regions will face significant structural changes.

Financial services in particular are expected to face up to £38bn in losses, putting over 65,000 jobs at risk. London is likely to see the back of large finance firms – or at least, sizable components of them – as they seek alternatives for their office functions. Indeed, Goldman Sachs has informed its employees of impending relocation, JP Morgan has purchased office space in Dublin’s docklands, and banks are considering geographical dispersion rather concentration at a specific location.

Depending on the type of business, some high-order service firms will behave differently. After all, depreciation of sterling against the euro can be an opportunity for firms seeking to take advantage of London’s relative affordability and its highly qualified labour. Still, it is difficult to predict how knowledge-intensive sectors will behave in aggregate.

Strategies other than relocation are feasible. Faced with economic uncertainty, knowledge-intensive businesses in the UK may accelerate the current trend of reducing office space, of encouraging employees to work from a variety of locations, and of employing them on short-term contracts or project-based work. Although this type of work arrangement has been steadily rising, it is only now beginning to affect the core workforce.

In Canada – also facing uncertainty as NAFTA is up-ended – companies are digitising work processes and virtualising workspace. The benefits are threefold: shifting to flexible workspaces can reduce real-estate costs; be attractive to millennial workers who balk at sitting in an office all day; and reduces tension between contractual and permanent staff, since the distinction cannot be read off their location in an office. While in Canada these shifts are usually portrayed as positive, a mark of keeping up with the times, the same changes can also reflect a grimmer reality.  

These changes have been made possible by the rise in mobile communication technologies. Whereas physical presence in an office has historically been key to communication, coordination and team monitoring, these ends can now be achieved without real-estate. Of course, offices – now places to meet rather than places to perform the substance of consulting, writing and analysing – remain necessary. But they can be down-sized, with workers performing many tasks at home, in cafés, in co-working spaces or on the move. This shifts the cost of workspace from employer to employee, without affecting the capacity to oversee, access information, communicate and coordinate.

What does this mean for UK cities? The extent to which such structural shifts could be beneficial or detrimental is dependent upon the ability of local governments to manage the situation.


This entails understanding the changes companies are making and thinking through their consequences: it is still assumed, by planners and in many urban bylaws and regulations, that buildings have specific uses, that economic activity occurs in specific neighbourhoods and clusters, and that this can be understood and regulated. But as increasing numbers of workers perform their economic activities across the city and along its transport networks, new concepts are needed to understand how the economy permeates cities, how ubiquitous economic activity can be coordinated with other city functions, such as housing, public space, transport, entertainment, and culture; and, crucially, how it can translate into revenue for local governments, who by-and-large rely on property taxes.

It’s worth noting that changes in the role of real-estate are also endemic in the retail sector, as shopping shifts on-line, and as many physical stores downsize or close. While top flight office and retail space may remain attractive as a symbolic façade, the ensuing surplus of Class B (older, less well located) facilities may kill off town-centres.

On the other hand, it could provide new settings within which artists and creators, evicted from their decaying nineteenth century industrial spaces (now transformed into expensive lofts), can engage in their imaginative and innovative pursuits. Other types of creative and knowledge work can also be encouraged to use this space collectively to counter isolation and precarity as they move from project to project.

Planners and policymakers should take stock of these changes – not merely reacting to them as they arise, but rethinking the assumptions that govern how they believe economic activity interacts with, and shapes, cities. Brexit and other fomenters of economic uncertainty exacerbate these trends, which reduce fixed costs for employers, but which also shift costs and uncertainty on to employees and cities.

But those who manage and study cities need to think through what these changes will mean for urban spaces. As the display, coordination and supervision functions enabled by real-estate – and, by extension, by city neighbourhoods – Increasingly transfer on-line, it’s worth asking: what roles do fixed locations now play in the knowledge economy?

Filipa Pajević is a PhD student at the School of Urban Planning, McGill University, researching the spatial underpinnings of mobile knowledge. She tweets as @filipouris. Richard Shearmur is currently director of the School, and has published extensively on the geography of innovation and on location in the urban economy.