The global trend for mass migration to large cities is creating a host of challenges for city planners trying to deal with dense metropolitan populations.

In most cases, creating living and working spaces for residents and commuters within limited space means building up, with gleaming skyscrapers and residential towers filling the skyline of the world’s major urban centres.

While building upwards is the obvious choice for space-conscious urban development, would it be possible to take the opposite approach and dig down to find new space? 

The exploding urban population has prompted the architecture, engineering and construction industry to take an inventory of how they do things and what changes need to be made for a profitable and sustainable future that meets the needs of urban dwellers.

Futuristic design concepts like earthscrapers, groundscrapers and oceanscrapers have emerged as possible building alternatives to counteract cramped urban spaces – both commercial and residential.

Earthscrapers, if brought to life, will transform how urban planning and living is imagined. With the capability to create new spaces for millions in areas with little or no open space available for building, earthscrapers have the potential to transform the future of urban design, movement and infrastructure.

As the name suggests, earthscrapers are the opposite of skyscrapers. They begin at surface level and extend downwards, just like a skyscraper extends upwards. While underground structures like car parking or a few levels of a shopping centre already exist, they are not the same as earthscrapers. 

But earthscrapers as a design solution to urban land constraint is currently only a concept with design proposals across the globe.

Grand designs

An innovative underground design created by Mexican architecture firm BNKR Arquitectura digs deeper than any other efforts. The earthscraper would delve 300 metres under Mexico City’s central Plaza de la Constitución to create a 65-storey inverted pyramid that saves space and references the most iconic edifices of the city’s Aztec ancestors.

BNKR’s concept is a reaction to the need to expand Mexico City’s residential, commercial and cultural capacity while also heeding the city’s planning restrictions, which include an eight-storey limit on building height. This kind of limit is relatively common due to ground quality or aesthetic concerns and is appropriate for a city that is particularly prone to earthquakes.

The inverted pyramid of the earthscraper would essentially create its own underground mini city while maintaining the purity of the historic architecture surrounding Mexico’s City’s main square. Under BNKR’s plans, the uppermost storeys would be dedicated to a museum exploring the city’s ancient roots and artifacts, many of which would likely be discovered during initial excavation.

The same futuristic architects have also started gathering funding for a bridge across Acapulco Bay. Primarily for road traffic and spanning three kilometres, it will also utilise often underused space, turning 700,000m2 into affordable housing.

By transforming its supporting structure into habitable spaces, private equity can be invited for its construction. This way, developers can acquire and sell on prime seafront real estate and the city solves one of its chief problems.

The project has been presented to local authorities for approval. Due to the scale, the titanic investment required for its construction and a shortage of vision, it was discarded as a utopian unviable solution, although they did mention that if BNKR could get investors interested in the project they might consider its viability. It has received support wherever it has been promoted.

New technology

Most people believe modern construction peaked with computer-aided design, but American firm Apis Cor completed a new Stupino, Moscow home in a day for only $NZ20,000 using mobile 3D printing technology. Completion, including the interior, took less than 24 hours for an open plan studio-style home, measuring 37m2.

Then there’s SAM the bricklaying robot, laying the groundwork for robotic construction. Designed to operate collaboratively with a mason, it can work six times faster than a human, laying 3,000 bricks a day.

Drones have made their way on to the building site too, with Japanese construction giant Komatsu using drones as “the eyes” for automated bulldozers. The drones scan the site and feed information to the machines to plot a course.

On the other side of the material spectrum, we have the use of plastic bricks. Danish student Lise Fuglsang Vestergaard developed the concept of recycling the plastic bags that dominate India’s landfills and turning them into bricks.

The colourful bricks can withstand up to six tonnes of pressure and if exposed to the monsoon season are likely to hold up better than current clay brick homes that are often washed away.