The author is David Sims and the subtitle is The Logic of a City Out of Control. It is interesting throughout for anyone studying urban density or informal land titles or urban sprawl or Third World mega-cities. This passage is off the central topics of the book, but I found it an interesting corrective to the usual picture:
There is a misconception held by many Egyptian professionals, especially engineers, that informal housing is haphazardly constructed and liable to collapse. However, such precarious housing is almost unknown in informal areas. Since informal housing is overwhelmingly owner-built without use of formal contractors, it is in the owner’s own best interest to ensure that care is taken in construction. In fact, one of the main features of informal housing construction is its high structural quality, reflecting the substantial financial resources and tremendous efforts that owners devote to these buildings. It is worth noting that in the 1992 earthquake in Cairo, practically all building collapses and the resulting fatalities occurred not in informal areas, but either in dilapidated historic parts of the city or informal areas…where apartment blocks had been constructed by (sometimes) unscrupulous developers and contractors.