Jane Jacobs Chapter 9 Summary

Jane Jacobs starts off chapter nine with her second condition for the existence of diversity that is necessary for blocks to be short. For a city to be successful, small blocks with a lot of places where people can turn to is required. She begins by using an example of a man living on a long street and his daily struggles. She also uses an example of people that form a pool of economic use only where their long, separated paths meet and come together in one stream being Columbus Avenue. In that neighborhood, there is geographically so little street frontage on which commerce can live. Jacobs explains that this is a typical arrangement for areas of city failure. She states, “ To contrast the stagnation of these long blocks with the fluidity
She begins the chapter by specifying that cities need old buildings so badly it is probably impossible for vigorous streets and districts to grow without them. There has to be a mixture and diversity of old and new buildings. The mixture regards the many ages and types of buildings. She clarifies that if a city has only new buildings, the enterprises that can exist there are automatically limited to those that can support the high costs of new construction meaning that there would be higher rents in the area. “Old ideas can sometimes use new buildings. New ideas must use old buildings.” Jacobs describes the only harm of aged buildings being that the harm that lies in everything being old and everything being worn out. Having this mixture of old and new, would create an economic necessity including the purpose of diversity. The economic effects of time are based by decades and generations. Jacobs points out that old buildings will still be a necessity when today’s new buildings are the old ones. She mentions that cities need a mingling of old buildings to cultivate primary as well as secondary diversity. Jacobs end the chapter by commenting that the economic value of new buildings is replaced alice in cities by spending more construction