May 7th

The Shanghai World Expo is the latest in a long line of International Cultural and Trade Fairs that have their origins in the Great Exhibition of 1851. The chinese offficials I met were very excited at this opportunity to show off China's capabilities in organising such an event which is bigger than anything before and has more countries participating than any previous event. Nowadays the main focus is on sustainable, low carbon development, the greening of cities and the creation of a fairer society. The event has cost China more than the Olympics and the organisers expect to have more than 70 million visitors this summer.

Each participating nation (or group of nations) promotes itself through an eye catching pavilion. Visitors are queuing for more than 3 hours to visit some of the more popular pavilions. The number of green roofs and living walls is a sign of how these features are now recognised as a key component of the green city.

Nations with green roofs or living wall on their pavilions included Switzerland, Germany, India, Saudi Arabia, Canada and Luxembourg, amongst others. Interestingly Chile had a green roof but had decided not to allow access, much to the dismay of my companion the top green roof expert Professor Mannfred Koehler. He used all his charms but it was apparently too dangerous for us to go up a ladder provided for staff only. The display of Chilean wines and the opportunity to taste them was a temptation but we settled for beer in an interesting bar attached to the Russian pavilion. Another common theme is rust and Luxembourg manages to combine vegetation and rust.

The site itself is a 5 square kilometre area of former steelworks next to the Huangpo River. Once polluted and now to become a new district of the city once the Expo is over. See http://en.expo2010.cn

None of the green roofs or living walls are outstanding examples of their type (some of the roofs are no more than lawns) and biodiversity does not seem to feature as much I think it should, especially in the International Year of Biodiversity but at least once the principle of vegetating buildings is established in people's minds it should be easier to bring about improvements. Living walls are all over the place in Shanghai now and there are many homegrown firms competing with others from France, Taiwan and Koreaoffering products of varying quality.

By the way - I liked the toilet with log walls.