Timber!

Buro Happold

11/05/2012 Written by: Matthew Smith 2 comments

I have been keen to promote timber as an engineering material in China since my first trip to Shenyang where the landscape looks very North European. I was recently sent a brochure from the Singapore based company Venturer who have joined forces with Cowley Timberwork in UK to promote use of Creative Structural Timber in Asia. Cowley Timber is a long time collaborator with Buro Happold and a number of our structures are featured.

We have recently had a client’s ambitions thwarted in Shangai where a beautiful timber roof designed in collaboration with PCP from Connecticut was changed to steel due to concerns from the local fire authorities. Not so much about the safety of the clubhouse building, but of the 30 storey residential tower that it abuts, which is probably a fair concern, albeit a shame.

The Chinese view the cutting down of trees as environmentally damaging which creates a stigma around timber that you don’t find in Europe, where sustainably managed forests are seen as an environmentally friendly alternative to concrete and steel. Carbon-neutral and Passivhaus dwellings are built around a core of engineered timber products. The Scandinavian and Central European forestry industry is thriving, and government bodies extol the benefits of planting and felling trees as fast as you can to save the planet.

The reality is not quite that simple. Young trees absorb more carbon than old, but a report from Friends of the Earth debunks the idea that felling old and planting young forests is beneficial.  Whereas a mature forest can store CO2 for hundreds of years in living trees, as soon as you cut the tree down and turn it into a product the process of releasing CO2 begins. This is particularly true of paper or other short life products, but less so for structural elements that may survive for many years if well detailed and maintained.

Over the period 1990 to 2010, China’s forested area increased at an average rate of 1.58% pa, gaining around 50mHa of forest in that period. The total coverage in 2010 was 200mHa (around 22% of total land area). As it happens, this is the same land area that was lost by Brazil in the same period (Brazil lost an average 0.5% pa, and currently has 520mHa, 62% of the country’s land area).

Planting trees can have other benefits of course. I recently read an article about birdlife in Beijing on the excellent Danwei.com. After a series of sandstorms brought havoc to the city in the 1990s, the government started a programme to plant forest in a ring around the north west of Beijing and Tianjin as an environmental buffer against wind blown sand from Mongolia. An unplanned side effect has been to attract hundreds of species of birds and animals giving rise to a significant increase in bird sightings in Beijing.

700Ha of trees were planted in the Beijing Olympic Park in 2008, so I was hopeful I might see some interesting birdlife as I set out from the Olympic Park subway station, on the way to the Pangu building the other morning. Unfortunately, I quickly became more interested in finding my way out of the Park…no mean feat since there are only four or five exits in this public space of 700Ha (in addition to the forest). I had time to notice that the Bird's Nest Stadium is still looking great, but the Watercube is looking a bit tired. People blame the dust and pollution, and certainly the ETFE cushions are looking well worn, like drum skins.

The Beijing air is a favourite water-cooler topic and many articles are devoted to it. The Beijinger magazine recently asked its readers to describe Beijing in six words. I particularly liked “First at bus-stop, last on bus”, but it was “500pm: blue sky with Chinese characteristics” that made me smile.

Having found my meeting (a bit late and frankly a bit sweaty) I was ushered up to the 20th floor where the sky was clear and the view was great. You could see the hills that lie to the north of Beijing, and the sprawling mess of highways and buildings to the south. It’s a great city despite the air pollution, but it could really do with some more trees. And a few more timber buildings...