Urbanization certainly isn’t a bad thing: concentrating population growth in cities and suburbs helps preserve tracts of land in rural areas for agriculture, preserves recreation and wildlife, and makes access to resources like education, medical care and jobs highly efficient. Of course, there are plenty of challenges that come along with it, not the least of which is finding space within cities for all of these new residents. By 2050, two-thirds of the world’s population will live in cities, a growth rate that’s far outstripping the availability of affordable and sustainable places to live.
How do we adapt our cities to these needs? Instead of tearing down existing architecture — a process that displaces current residents and often leads to a loss of character, culture and sense of history in a given city — we could potentially build on top of it instead. According to Vancouver-based architect Michael Green, wood is the way forward.
“We need to start building up, and stop tearing down,” he says. “We have an alternative. A building extension constructed with a timber frame can be a fast, sustainable and inexpensive solution.”
“Today, engineered wood offers designers an incredible opportunity to meet this challenge. New wood products allow designers to build taller structures that are much lighter than alternative materials (steel and concrete) while still meeting strict criteria for fire resistance and/or seismic challenges. All this can be achieved using a natural, beautiful material — grown by the sun.”
Not all buildings are strong enough to support additional floors made of wood or any other material, but research suggests that at least one-fourth of them are, making them potential bases not only for new timber towers but also for entire elevated communities. That’s the idea behind the Plan B Architecture “City Above the City” competition by Metsä Wood, a project exploring the possibilities of using wood in urban construction.
“A City” by architects Carlos Romero and Bernardo Santana envisions how this could look in Mexico City. Their competition entry offers a potential solution for sustainable urban growth in the world’s 12th most densely populated city, which is home to more than 20.2 million inhabitants. Building up using renewable, natural materials preserves the city’s architectural heritage, and the concept includes lots of common areas and greenery, too.
The modular extensions feature variable floor plans and are limited to six stories to avoid overpopulating individual city blocks or blocking off sunlight to the streets below. Since the design is so adaptable, it works for all kinds of different rooftops, and can be altered to fit other cities as needed.
The triangular base shape creates a covered common area connecting multiple units, and space is left open on either side for balconies and uncovered outdoor space. The rounded roof design enables rain catchment, and lots of space is left open to the air for cross-ventilation. The architects emphasize a need to maintain balance between the width of the street, the height of each building and a scale that is comfortable for all residents of the city.
While this particular entry didn’t win the competition, it’s an interesting, real-world proposal that could be adapted to cities now, rather than an idealistic concept relying on technology and infrastructure that doesn’t yet exist. Check out the winners of the competition at the Metsä Wood website.