Welcoming Back Wood to the Urban World
Entering 2019, the bland result of the international climate conference in Katowice might for many have left a feeling of going backwards in time. Looking at the past may, however, prove hopeful for combatting one of the biggest worldwide climate sinners: building with concrete
Photo by Bart Lumber (Flickr)
by Isabella Engberg
In 1666, the City of London stood in flames, reaching temperatures of 1,250° Celsius. The wooden houses and thatched roofs of the claustrophobic cobbled alleys were blamed. In the UK, the year marked a new era of building with bricks and later, steel and concrete. But ‘outdated’ is no longer a label suitable for one of the world’s oldest building materials.
Global Green Housing Trend
Between 5 - 8 % of global greenhouse emissions can be traced back to modern construction practises using concrete and steel. As a contrast on this carbon footprint spectrum, there is the building material of the past - wood. As it is produced, it naturally locks away carbon dioxide. Although still a more expensive building material due to competition, wood can and is now being used in large-scale structures all over the world, for example in Australia, Austria, Canada, and Norway. Even despite its climate-unfriendly White House, the USA is also seeing timber towers built by independents and companies in New York, Denver, and Chicago.
Traumatised by a world-history of city fires, however, it seems only natural that modern city councils are concerned when considering new buildings in wood. An unnecessary concern today, many developers argue. New structural engineering has allowed wood a comeback for urban architects, promising a high degree of fire-safety. New cross-laminated timber and weather coating secures a safety grade equal - and in some respects superior - to that of steel and concrete. Firstly, the coating of the wood prevents kindling. Secondly, charred timber beams actually hold constructions better than steel beams, which are known to melt, Anthony Hopkins, a founding director of a wood building architect firm tells the BBC.
There are other advantages to building with wood: it is suitable for sites often hit by earthquakes; fewer lorries are needed for the transportation of the lighter product into the city; and wood does not need to dry on-site like concrete, making the building process shorter – an important aspect in hectic cities. A concern, however, for city planners and a great many conventional architects, has been the need to make the wooden structures tall, especially in the great metropolises, where ground space is costly. Indeed, wood is a very light material, which can prove difficult when tackling the heavy winds skyscrapers otherwise need to resist. This can be achieved by adding weight from other materials.
Although possible, Thistleton argues, there really is no need to build wooden buildings that high: “The need to build the highest is just a manifestation of the ego of the architect.” Instead, he argues, the most important aspect when building with timber is to act responsibly for the environment.