SHANGHAI, July 30 -- WITH their huge size and high ceilings, factories have great potential which makes them ideal for artists and for people seeking alternative forms of living.

The key to redesigning an old factory is to understand the building and its specific spatial, structural and architectural qualities. Then the renovator can begin a clever transformation. The result turns out to be that users can experience a new way of doing things - living, working or being entertained is a different and maybe better way than in a building designed for the purpose.

Usually, the interior design is already there. The best way for an architect would be to shut up and let the building speak.

Reusing old buildings is nothing new, because it simply makes sense - look at Rome's Colosseum. It has been reused differently more than 40 times. What is new is that people destroy things in order to build new structures and after maybe just a decade, destroy them again. It would be interesting to find out the purpose of that.

The renovation of old factories started in the 1960s in New York. And through a process called "gentrification" in which artists move in and rich young people follow them when the artists get bored, can't afford the rent and move out.

Now every major Western city has a reused factory district, just like every Chinese city has a Xintiandi.

In my eyes, one of the most wonderfully renovated projects ever is "Creative Shanghai" north of Yangpu Bridge. It was done by Teng Kun-Yen, a designer from Taiwan. The site deliberately has an unfinished appearance.

Other projects in the city such as Bridge 8 on Jianguo Road, In Factory on Kangding Road and Red Town on Huaihai Road are also worth looking at.

I recently read that factories will be preserved in the world Expo Site and with the cleverness of renovators, they should be great pieces of work.