This is a really good read. It's an analysis of what makes houses and buildings good. I came to it via the TV series he made based on it (The Perfect Home), which is also good but has less to it.
In any case, this book gives you a lot to think about and has some really interesting stuff about the history of architecture. It also made me rather dissatisfied with my own house, but at the moment there is no way I can do anything about that.