Two decades from now, I doubt that the home building industry, so called, will even exist as we have known it.

In many places, the zoning prohibits the mixing of retail and residential. This stupidity has been accompanied by stupidities in municipal policy, such as disallowing accessory apartments - under the theory that renters are incapable of behaving decently.

There is not going to be a "hydrogen economy," and no combination of alternative energy systems or fuels will allow us to continue the suburban pattern. It's finished. We will, however, desperately need to grow more of our food closer to home, and so the preservation of agricultural hinterlands is of great importance. But don't expect the fiesta of suburban construction to continue more than a few more years.

The skyscraper - any building over seven stories really - will come to be seen as an experimental building type that doesn't work well in an energy-starved economy.

When a society is stressed, when it comes up against things that are hard to understand, you get a lot of delusional thinking.

In my view, suburbia in general has very poor prospects. I think it will only become devalued and probably more dangerous. It's chief characteristic was that it represented a living arrangement with no future - and that future is now here.

It is worth remembering that our cities occupy important sites, and therefore some kind of settlement is liable to be there.