Building Tall is Building Less
Building tall is not building more, but arrogantly building less for more profit.
According to The Little Book of Density, there are 23 definitions of what density means on a given site. These definitions change depending on who is measuring them, and can relate to everything from the supply of housing, to the ratio of plot development, to the net sellable area. Definitions of density also change at different scales and with different uses, from city-wide habitable rooms per hectare, to building block coverages measured to the kerb.
This ambiguity around the term results in its appropriation by different stakeholders for different agendas. For example, the priority of planners in local Councils is to encourage density to increase the number of habitable rooms per hectare, in line with Government targets. Whereas on a particular site, developers are more concerned with plot-specific density measures, such as floor area ratios or plot coverage, in line with commercial profit targets.
This means that situations arise where both parties are earnestly arguing for more density to meet their targets, but the ambiguity over what form the density takes in the development can result in the overcompensation of height and scale. The argument used by developers in these cases is that in order for them to meet these housing density targets, they must increase the scale of other parts of the development in order to meet their profit margins.
The obnoxious tower developments which dominate London’s skyline should remind us that density and scale are not the same thing, and many of the problems resulting from these conflicts could have been mitigated through a proactive understanding of the relationship between these two terms. In fact, around half of England’s local councils are expected to fail to meet their housing targets this year, primarily due to their struggle to successfully negotiate with developers. According to Sadiq Khan, London needs to be building 66,000 homes per year just to keep up with the demand for new housing, within in the context of an existing national four million home deficit.
Even the definition of ‘tall building’ is subjective. The GLA’s draft New London Plan policy D8 describes them as any buildings that are ‘substantially taller than their surroundings and cause a significant change to the skyline.’ It also allows for each local council to interpret this ambiguous term in any way they wish.
For the sake of this article, let us consider the definition of density based on population or the number of inhabitants per square km. This is the most common definition used by the Government to measure housing provision.
With this definition, the Greater London area surprisingly has a very low density compared to other European cities, despite its number of tall buildings. For example, Barcelona has a density of around 16,000 people per square km, roughly three times that of Greater London, despite the fact that its urban fabric is almost entirely made up of low- to medium-rise buildings.
Of course, this may be because Greater London encompasses the lower-density suburban outskirts, and therefore a measurement of average density is not representative of the city centre. However, what is most surprising is that the City of London, considered to be at the city’s heart, has a density of only 2,655 inhabitants per square km. This is a third of the London average and nine times less than Barcelona. This is predominantly because the majority of tall buildings in the City of London, which give the perception of high density, are not residential, but commercial enterprises.
This shows that, although an area may appear dense in its scale, the definition of density through which the city is viewed can give distorted representations of reality. The City of London is an example of how apparent density can provide incredible returns on investment but does very little to tackle the greater problem of the city- and country-wide housing shortage.
Barcelona is a testament that residential densities can be increased without the need to build high. Given such examples, why are councils still approving ill-conceived tower blocks which dominate London’s skyline? The answer, unfortunately, is comprised of four problems in the understanding of tall buildings:
“We have to build high to provide enough housing”
The first misconception is that building tall means building more. A common argument made by developers is that in order for the development to break even, additional floors must be added. These additional floors are not intended to simply provide more sellable units but are to increase the value of the units sold.
Fundamentally, it is perceived to be much easier (and cheaper) to build additional floors on top of each other, than it is to build many smaller buildings with separate cores, entrances and circulation spaces. More often than not, this is a fabricated excuse, but it is difficult to counter without a thorough examination of the profit-loss analysis of the development.
In fact, high rise residential buildings cost 30–40% more per unit than low-rise. This is due to increased costs associated with wind-loading, foundations, higher water pressures for services, and complex logistics involved in construction. On top of this increased construction cost, as the building becomes taller, more floor area is taken up by services, and therefore the net sellable area shrinks. So the simplistic argument of “tall means more” is not entirely accurate.
The Paddington Pole is one such example of a residential proposal which made the argument for height to increase density. The tower, designed by Renzo Piano, faced fierce opposition from architects, residents, Westminster Council and campaigners such as SAVE and Historic England, due to the damage it would cause to the existing historic fabric of the area.
Sir Terry Farrell was one of the architects who opposed the scheme and published his own alternative proposal, which would “provide over 1,000 homes against the 350 offered by Piano’s “Paddington Pole” and double the development area” all whilst retaining a height below 55m. When considered against such a proposal, the Paddington Pole seemed ill-considered and arrogant. Building tall, in this case, really did mean building less.
The irony of the Paddington problem is that the proposal which followed the ‘pole,’ known as the ‘Paddington Cube,’ had a reduced height and received planning permission, however, being an office building, it contains no residential units. It therefore contributes nothing to the residential density of London, nor the council’s targets for housing provision. The damage of this new proposal is twofold because its construction will lock the wider site out from any such lower-rise residential development in the future.
This is not to say that all tall buildings should be avoided at all costs because there are certainly areas which would benefit with such a treatment, as Farrell would agree. However, there are definitely areas of London where the effects of tall buildings would be catastrophic to the existing urban fabric.
“It will be a new signature landmark building for the city”
The second problem is that the egotistical hangover from the capitalist development boom, which began in Chicago and New York in the last century, has not yet faded away. Critic Colin Marrs argues that “designing skyscrapers has gone from something macho to something that is a bit embarrassing” and I’m sure many would agree.
Buildings which tag themselves with the terms ‘landmark’ or ‘signature,’ such as Norman Foster’s recently approved Tulip Tower, should immediately be met with scepticism. The first reason for this is that these towers contain none or very few residential units, and therefore do not contribute in any way to the residential density of London. In and of itself, this should not be a reason to reject such towers outright, but should be made clear in the discussion of their purpose in the context of a city of low residential density with a critical shortage of housing as outlined previously.
The second is that these towers are often designed from an instagram-cityscape perspective, and not from the perspective of the human. Foster’s ‘tulip tower’ is an example of this strange phenomenon. If you really look at how these signature towers are represented, you realise that the building is shown only from the perspective of birds. No human will ever see the building from such angles, unless of course you frequent London’s sky in your helicopter. The way these buildings will be experienced by those who do not occupy the building, from the ground, is almost entirely ignored. Don’t believe me? Have a look for yourself.
Foster’s ‘Tulip Tower’ is, of course, not residential, however, the same strange obsession with inhuman vantage points can be seen in the designs for the ‘signature’ residential towers approved in Blackfriars.
If we want our cities to be more enjoyable, healthy places to live and work, we must remind ourselves that large art sculptures, empty paved squares and vehicle turning circles do not constitute high quality public realm around the base of these tall buildings. In fact many of the recent criticisms of the ‘Paddington Cube’ proposal are focused on the poor quality public realm which surrounds it.
This is not to say that tall office buildings cannot do a great deal of benefit to a city’s skyline (and therefore its ‘brand’), but by detaching one’s focus from the ground, the interaction between the tower and the site is often ignored and undervalued as a piece of the city’s urban fabric. In every case where a tall building is proposed, proper consideration must be given to the interaction between that building and the surrounding area at the ground level.
“We will reduce the height a little to satisfy your concerns”
The third problem is that our planning system is reactionary, not proactive. Developers are often the first to make a proposal for an area of city, which is invariably an over-scaled, ostentatious scheme, with the knowledge that the planners will have to fight to reduce the scale to anything appropriate. As any novice haggler will tell you, the person who proposes the first price is immediately on the upper hand in any trade.
Factor into this that councils need developers to build in their boroughs in order to meet their own legally binding targets, and you can see why it is so hard for councils to maintain authority over these larger developments. Developers can (and often do) hold the whole development to ransom, if it means they can add a few more storeys onto their towers. After all, it is the local council, not the developer, who will be fined for not reaching their housing targets by a certain date, and developers know this.
“There is no city-wide tall building strategy”
The fourth and most frustrating point is that there doesn’t seem to be an effort to address these problems from the wider perspective of the city scale. Whether this comes from a lack of communication between councils or a misunderstanding of the effects of tall buildings on our cities, small compromises made at a plot scale often compound to have massive detrimental impacts on the quality of our city at the human scale.
Surprisingly, there is no city-wide plan for tall buildings in London. The skyline of London is not designed, planned nor regulated at a city scale. Rather, the forces which dictate its forms are predominantly localised masterplans (where they exist) and viewing corridors within each individual borough’s unique planning process.
A unified body of architects, campaigners, councils, developers and residents working collaboratively towards a city-wide tall building strategy for London would have resolved disputes such as those seen around Paddington, before they ever happen. This cross council group could determine in which areas tall buildings are appropriate and which they are not, and ensure proper specialist consideration is given to the effects of such buildings on the surrounding cityscape.
The draft New London Plan by the GLA goes some way to accepting that tall buildings can have a detrimental effect on our cities and to the creation of such a city-wide strategy. However, as many of the comments on the draft show, there is a consensus that these measures do not go far enough to proactively discourage tallness for tallness’s sake. The ambiguity around terminology, and the inconsistency with which each local council interprets the definition of ‘tall buildings’ also inhibits the creation of a effective standardised city-wide approach.
London is a leading world city, so the presence of tall buildings is inevitable. However, with a staggering 541 tall buildings in the pipeline, many of which proposed for the outer-boroughs where the existing fabric is low to medium-rise, it seems careless not to have a unified city-wide tall building strategy.
Building tall does not mean building more, and councils need to be clear about exactly what they are encouraging ‘more’ of. More height? More housing? or more sellable area?
