Tall buildings are a product of our modern world. They are enabled and driven by technology, fuelled by economics and globalisation, and are thus sensitive to social, political and financial events, whether local crises or global emergencies. London is grappling with the consecutive events of Brexit, Grenfell, and Covid-19, while our entire planet is overshadowed by the Climate Emergency.

 

The rapid urbanisation of larger cities globally has created huge demand, with 60% of all people expected to be living in cities by 2030, and almost 70% by 2050. Densification compounds this. Less urban land is available, while consecutive layers consequent to previous development – particularly in historic cities such as London – sterilise the ground, making it harder to construct new foundations. Combined, these factors have accelerated the construction of tall buildings rapidly, with more built in the last two decades than in the previous 120 years. 

Amidst the Climate Emergency, and with globalisation’s potential for equitable progress coming into question, the ‘city of the future’ model is being reassessed, and with it the tall-building typology. With a scale to magnify any client brief and every design and procurement outcome, tall buildings must move beyond a single intended use for a given timescale. Moreover, they must become transformers: inherently able to adjust to future requirements, and designed for ‘long life, loose fit, low energy’. Any obsolescence of buildings at this scale should be socially unacceptable, and this should be a founding principle for all future tall-building design.

 

Buildings and their structures should provide an adaptable framework that allows multiple or hybrid uses throughout the project’s lifetime. This adaptability will be proportional to the building’s ambition and budget. A hierarchical structure could achieve this; split into primary ‘permanent’ and secondary ‘temporary’ elements, with the latter embodying an ability to easy adjust through time, to suit changing requirements and uses.

A hierarchical structure provides an adaptable framework

This adaptable framework could allow the fabric of an entire block-section to be changed to a different material, such as timber, or internally reconfigured to suit differing use. This separation – villages within a vertical city – creates further opportunity: with plant levels spread more evenly throughout the volume, the core and risers require less floor area, while the services’ adaptability is enhanced. We create a universal, infinitely reusable tall building.

 

Tall buildings are no longer limited to simple extrusions of a single floor plate. An independent operation of vertical or horizontal sections will allow services and circulatory layouts to be optimised for each use. Residential floors can be served by centralised cores, while office floors can be served by cores at one edge to create large, uninterrupted functional areas. Amenities and other uses can be provided not just at ground level, but throughout the building’s height.

 

Technology will continue to inform the tall building’s function and appearance. Recent vertical-transportation advances, such as double-decker lift cars, require fewer lift shafts and thus allow more efficient core areas. Soon, ‘free movement’ lifts may surpass these, with cars operating both vertically and horizontally, and independently sharing shafts. This will doubtlessly accelerate the rise of interconnected tall-building clusters, wherein buildings are no longer designed as stand-alone structures. Connective links may share more than just circulation, forming each cluster into a resilient, true vertical city.

 

With cores no longer expanding proportionally with building height, a paradigm shift in tall-building engineering could bring in adaptable, permeable ‘soft cores’, opening up multiple avenues for building stability, while other structural elements resist horizontal load. A perimetral structure allows greater efficiency, and can multitask as a passive envelope element when taken beyond the thermal line; becoming an exoskeleton, and part of the architectural appearance. 

 
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