With property prices rising and space rapidly running out in big cities, innovative property developers are going underground in search of a solution.
Although underground construction is still in its infancy, there are several large projects on the horizon including Mexico City’s 75-storey ‘Earthscraper’ and Singapore’s Jewel Changi Airport. In this article we’ll look at some of the pros and cons behind this ambitious new form of construction.
Building underground offers several advantages. The main advantage is simply, saving space.
In extremely cold climates it can offer a stable temperature year-round, leading to lower heating bills and greater energy efficiency. Intense heat and high humidity levels can also cause problems for construction projects above ground, so moving underground may be beneficial in hot climates as well.
By their nature, underground buildings are likely to include other environmental features such as rainwater harvesting, which can help reduce the environmental impact of the building. Singapore’s Jewel Changi Airport is set to have a central water feature, known as the Rain Vortex, pouring 500,000 litres of water down a 40 metre drop to create the world’s largest indoor waterfall. Rainwater will also be used for internal facilities, and the Rain Vortex will help to maintain a cool and fresh environment.
Natural light can be transmitted far underground using fibre-optic cable or arrays of anodised aluminium panels - effectively large scale versions of the light tunnels that are sometimes used to transmit light into windowless rooms in domestic dwellings.
There are, of course, disadvantages to underground construction.
Building underground is primarily intended for densely populated areas, but these are also the areas where underground obstructions are most readily found. Foundations of existing buildings need to be taken into consideration, particularly high density buildings such as skyscrapers, with their substantial foundations. Then there are underground power cables, sewage pipes, subways and other underground obstacles to be navigated.
Mexico City’s Earthscraper, which would descend a proposed 75 storeys, also faces concerns about the potential impact that underground construction could have on nearby historic buildings. It was proposed largely because local laws protect historic buildings by prohibiting the construction of buildings over eight stories. Ironically, constructing something so deep underground to combat these laws may actually pose a larger danger to those historic buildings.
All of these variables mean that the costs of building below the surface are still largely unknown. In despite of these variables, underground construction is still a very interesting topic of discussion and definitely a potential construction trend of the future.