[crdoconnor]

>High-rise buildings are a hugely inefficient use of land and energy.

High rise buildings are MORE efficient, not less. The more dense the city, the more energy efficient it is: http://www.citylab.com/work/2012/04/why-bigger-cities-are-gr...

>But it is not height restrictions that preclude that kind of development in central London. The foremost problem is a lack of available land.

You just have to look at the number of people packed into a smaller area in Manhattan to see that that isn't true.

>We could build millions and millions of houses in the green belt.

You could also build millions of apartments inside it and then maybe people wouldn't have to live in Uxbridge and Barnet AND you wouldn't have to make air quality in London even worse.