Alain de Botton is wrong. London needs more tall buildings

From New York, to London, to Tokyo, tall buildings are a familiar part of the cityscape – though not always a popular one.

In Paris, there is vocal opposition against proposals for three new towers in the city centre – the Tour Triangle, the Tour Duo and the new Palais de Justice. Meanwhile, London appears set for a skyscraper boom, with hundreds of new towers to be built in the UK capital over the coming years.

Some people are concerned that these new developments will destroy the cities' historic skylines. In particular, Alain de Botton has warned that London could be turned into “a bad version of Dubai or Shanghai”.

But this comparison is laughable – and the fear that London is set to be overrun by empty crystalline towers is entirely misplaced.

Research tells us that London has 263 buildings of 20 storeys or more in height, either under construction or proposed to be built. To many, this is a huge and frightening number.

But let’s put this figure in context: Shanghai had 6,266 20-storey towers already built by 2014, with thousands more in the pipeline. China is without doubt the global centre of tall building construction. To accommodate an extra 350m urban dwellers by 2025, it is estimated the country will build 50,000 new skyscrapers. This is 190 times the number proposed in London, and equivalent to 10 New York Cities.

Shanghai’s vertigo-inducing skyline. Image: sama093/Flickr, CC BY-NC-ND.

Meanwhile, Switzerland – a country known better for timber chalets than glass skyscrapers – has plans to build between 140 and 160 new towers. The country has a population similar to London’s, but much more land to build on, so you’d think there would be relatively little demand for high-rise buildings. And yet Switzerland is still proposing to build almost two-thirds as many towers as London.

When it comes to tall residential buildings, those with roughly 45 storeys or more are likely to be more than 150 metres tall. London currently has 16 towers of this height, while Dubai has 146, and Shanghai has 125.

Should all the proposed towers get built, London will see this figure rise to 47. This might sound like a boom to Londoners, but on an international scale, it is actually little more than a blip. London is not going to turn into Shanghai-on-Thames any time soon.

Getting dense

One of the main arguments for building tall is to create greater density. By stacking dwellings on top of each other, a plot of land can accommodate more people, and reduce the need to build outwards into the countryside.

Many argue that low-rise and terraced housing can achieve the same density as towers. But while this may be possible on larger sites, where the inclusion of streets and squares is viable, when it comes to developing London’s smallest brownfield sites, the only way to accommodate higher numbers of houses is to build upwards.

Paris is often cited as the prime example of a low-rise, high-density city. The city accommodates 21,500 people per km2, making it one of the densest in the Western world. And yet there has not been a single skyscraper built in central Paris since 1973, when the 59-storey Tour Montparnasse became the “most hated building in Paris”. Instead, the focus has been on buildings of six to eight storeys.

Nonetheless, the idea that Paris is a city without skyscrapers is actually a myth. It has many tall buildings, but they're clustered in a region known as La Défense, at the outskirts of the city, away from its historic centre. This has allowed Paris to develop a dense office district and compete financially with other cities, while maintaining the character of its low-rise boulevards in the centre.

These towers may be outside the political boundary of Paris proper, but they're still part of the urban landscape: they are physically and visually connected to the city via the Axe historique, which links La Défense with landmarks such as the Arc de Triomphe and Louvre. If we include La Défense, Paris actually has more skyscrapers than London, with 19 taller than 150 metres in height, compared to London’s 16.

La Défense towering on the horizon. Image: xeno_sapien/Flickr, CC BY.

So Londoners shouldn’t think that the skyscraper is an enemy of the historic low-rise city: far from it. We need to recognise that high-rise construction can be a key tool to preserve the historic urban realm, allowing the development demanded by economic and population growth to be diverted away from historic areas, preserving their character for residents and tourists alike.

The height of the housing crisis

It’s not just high-rise office blocks that attract opprobrium: residential towers are also accused of assaulting the eyes. Currently, London is experiencing a housing crisis: 210,000 new dwellings will be needed over the next five years to cope with population growth. But future Londoners will not be forced to live in towers.

Even if all 263 of the planned skyscrapers actually get built, they will only create 14,800 new homes, meeting just 7 per cent of the total demand for housing. The remaining 93 per cent is likely to come from low-rise buildings, which should go some way to reassuring the skyscraper sceptics.

Another criticism of London’s residential towers is that they are creating "safe-deposit boxes in the sky"; investment homes for the super-rich, which will remain empty until they can be sold on for a tidy profit. While it is true there is a shameful lack of affordable housing in modern high-rise apartment blocks in London, there is little evidence that new units are going to remain unoccupied.

Houses, or homes? Image: aesum/Flickr, CC BY-NC-ND.

This is not to say that empty houses are not a challenge in London: in 2014 alone, more than 20,000 dwellings were vacant for longer than six months. The borough of Lambeth – home to several tall residential towers – had the highest number of empty houses, with 1,354. But the borough of Kensington & Chelsea, characterised by low-rise, high-density architecture, was placed second, with 1,250 vacant dwellings.

Empty millionaire pads aren’t only found on top of towers, but across all luxury developments, including low-rise housing. The issue of empty houses won’t be addressed by stopping the spread of skyscrapers.

Detractors of the high-rise will also tell you that tall buildings are expensive to build and maintain, and unsustainable due to high energy needs. This, they say, makes the tall building unsuitable for affordable housing. Again though, this doesn’t tell the full story: while building vertically is often more expensive up front, there can be notable energy and cost savings over the longer term.

Stacking up housing allows residents to live closer to the centre of a city, giving them better access to public transportation and cultural facilities, and reducing the energy needed for transit. Heating is the largest consumer of energy in our dwellings, and here tall buildings offer benefits, too. Due to their compact form, high-rise towers lose very little heat through their walls, and have been found to have the lowest heating needs of all building types. This means a reduced carbon footprint, and lower bills for residents as energy prices continue to rise.

It would be foolish for anyone to suggest London should follow the path of Dubai, Hong Kong and Shanghai and attempt to house its population entirely in tall buildings. But surely it’s just as foolish to limit all London’s future housing to terraces, or six to eight storey buildings, as those like de Botton are suggesting.

London doesn’t need just one or two building types – it needs a wide mix of housing. These should probably be mostly low or medium-rise buildings, as is the case today. But they should also include strategically-placed skyscrapers, to increase population density and help London meet its desperate housing needs. The Conversation

Philip Oldfield is Assistant Professor and Course Director, Masters in Sustainanble Tall Buildings at University of Nottingham.

This article was originally published on The Conversation. Read the original article.


Green roofs improve cities – so why don’t all buildings have them?

The green roof at the Kennedy Centre, Washington DC. Image: Getty.

Rooftops covered with grass, vegetable gardens and lush foliage are now a common sight in many cities around the world. More and more private companies and city authorities are investing in green roofs, drawn to their wide-ranging benefits which include savings on energy costs, mitigating the risk from floods, creating habitats for urban wildlife, tackling air pollution and urban heat and even producing food.

A recent report in the UK suggested that the green roof market there is expanding at a rate of 17 per cent each year. The world’s largest rooftop farm will open in Paris in 2020, superseding similar schemes in New York City and Chicago. Stuttgart, in Germany, is thought of as “the green roof capital of Europe”, while Singapore is even installing green roofs on buses.

These increasingly radical urban designs can help cities adapt to the monumental challenges they face, such as access to resources and a lack of green space due to development. But buy-in from city authorities, businesses and other institutions is crucial to ensuring their success – as is research investigating different options to suit the variety of rooftop spaces found in cities.

A growing trend

The UK is relatively new to developing green roofs, and governments and institutions are playing a major role in spreading the practice. London is home to much of the UK’s green roof market, mainly due to forward-thinking policies such as the 2008 London Plan, which paved the way to more than double the area of green roofs in the capital.

Although London has led the way, there are now “living labs” at the Universities of Sheffield and Salford which are helping to establish the precedent elsewhere. The IGNITION project – led by the Greater Manchester Combined Authority – involves the development of a living lab at the University of Salford, with the aim of uncovering ways to convince developers and investors to adopt green roofs.

Ongoing research is showcasing how green roofs can integrate with living walls and sustainable drainage systems on the ground, such as street trees, to better manage water and make the built environment more sustainable.

Research is also demonstrating the social value of green roofs. Doctors are increasingly prescribing time spent gardening outdoors for patients dealiong with anxiety and depression. And research has found that access to even the most basic green spaces can provide a better quality of life for dementia sufferers and help prevent obesity.

An edible roof at Fenway Park, stadium of the Boston Red Sox. Image: Michael Hardman/author provided.

In North America, green roofs have become mainstream, with a wide array of expansive, accessible and food-producing roofs installed in buildings. Again, city leaders and authorities have helped push the movement forward – only recently, San Francisco created a policy requiring new buildings to have green roofs. Toronto has policies dating from the 1990s, encouraging the development of urban farms on rooftops.

These countries also benefit from having newer buildings, which make it easier to install green roofs. Being able to store and distribute water right across the rooftop is crucial to maintaining the plants on any green roof – especially on “edible roofs” which farm fruit and vegetables. And it’s much easier to create this capacity in newer buildings, which can typically hold greater weight, than retro-fit old ones. Having a stronger roof also makes it easier to grow a greater variety of plants, since the soil can be deeper.

The new normal?

For green roofs to become the norm for new developments, there needs to be buy-in from public authorities and private actors. Those responsible for maintaining buildings may have to acquire new skills, such as landscaping, and in some cases volunteers may be needed to help out. Other considerations include installing drainage paths, meeting health and safety requirements and perhaps allowing access for the public, as well as planning restrictions and disruption from regular ativities in and around the buildings during installation.

To convince investors and developers that installing green roofs is worthwhile, economic arguments are still the most important. The term “natural capital” has been developed to explain the economic value of nature; for example, measuring the money saved by installing natural solutions to protect against flood damage, adapt to climate change or help people lead healthier and happier lives.

As the expertise about green roofs grows, official standards have been developed to ensure that they are designed, built and maintained properly, and function well. Improvements in the science and technology underpinning green roof development have also led to new variations on the concept.

For example, “blue roofs” increase the capacity of buildings to hold water over longer periods of time, rather than drain away quickly – crucial in times of heavier rainfall. There are also combinations of green roofs with solar panels, and “brown roofs” which are wilder in nature and maximise biodiversity.

If the trend continues, it could create new jobs and a more vibrant and sustainable local food economy – alongside many other benefits. There are still barriers to overcome, but the evidence so far indicates that green roofs have the potential to transform cities and help them function sustainably long into the future. The success stories need to be studied and replicated elsewhere, to make green, blue, brown and food-producing roofs the norm in cities around the world.

Michael Hardman, Senior Lecturer in Urban Geography, University of Salford and Nick Davies, Research Fellow, University of Salford.

This article is republished from The Conversation under a Creative Commons license. Read the original article.