On May 23rd, 2007, the world passed a very specific milestone. That was the day, according to a demographic study, that the global population went from majority rural to majority urban. The scales tilted towards cities, which were growing in both number and size.
At 21 million citizens, Mexico City is one of the largest, and it’s little surprise that it has been growing upwards. Torre Reforma is one of several striking new skyscrapers in the region that are breaking new ground in design and sustainability.
This 57 storey tower has been certified LEED Platinum, and won the International Highrise Award in 2018, named as the best skyscraper in the world.
These things are no doubt subjective from an aesthetics point of view, but it certainly has a stack of environmental credentials. For a start, the building is surprisingly narrow for a tower of its height. The floor plan forms a triangle shape with glass along the longest side, so that natural light spills into the whole building. At the same time, the trilaminated glass and brise-soleils keep the building from overheating.
The narrow shape means the building can be naturally ventilated in good weather. A smart building control system opens the vents before dawn when the air is cool, releasing warm air from inside and drawing in fresh cool air, like a breath to start the day.
The tower captures rainwater and reuses it in bathrooms. It also processes wastewater on site, recycling it for use in an energy-efficient ice-based cooling system that kicks in on hot days.
Mexico City is at risk of earthquakes, so Torre Reforma is designed to handle a ‘one in 2,500 years’ event. The two concrete walls at the rear of the tower, which are actually the tallest walls of any building in the world, can ‘bend’ in response to a quake. I find that hard to imagine, but Mexico has been building earthquake-proof towers for a while. The neighbouring Torre Mayor has withstood two earthquakes over 7 on the Richter scale without damage, and with some residents not even noticing, so they know what they’re doing.
Finally, the skyscraper stands on a historic boulevard through the city, the Paseo de la Reforma. There’s a notable neo-gothic house on the corner, built in 1929 and well worth preserving. Instead of knocking it down, the builders shifted it sideways, dug out nine storeys of basement underneath it and then put it back. It now forms the entrance lobby to the tower, a clever transitional space that welcomes people off the street.
It’s hard to know whether buildings like this can ever be as low carbon as they need to be, with the sheer weight of steel and concrete involved. And there’s no doubt that this is architecture for the global elite. But the world’s megacities aren’t going anywhere. Skyscrapers will continue to be built, and the more of them strive for sustainability like Torre Reforma, the better.