As you’ve probably realized by now, I think Christopher Alexander is the ultimate environmental (architectural) psychologist. The deep and practical thought he put into each of the patterns of building in his Pattern Language represent the way architects and planners need to start thinking about the built environment. Today I’m sharing another pattern I particularly like – this one relevant to my specific interests in social patterns in residential settings.
#37 – House Cluster
“People will not feel comfortable in their houses unless a group of houses forms a cluster, with the public land between them jointly owned by all the householders…
“Hebert Gans in The Levittowners has collected some powerful evidence for this tendency. Gans surveyed visiting habits on a typical block tract development. Of the 149 people he surveyed, all of them were engaged in some pattern of regular visiting with their neighbors. The interesting finding is the morphology of this visiting pattern.
“Consider the following diagram… There is a house on either side, one or two across the street, and one directly behind, across a garden fence. Ninety-three percent of all the neighborhood visiting engaged in by the subjects is confined to this spatial cluster.
“The beauty of this finding is in its indication of the strength of the spatial cluster to draw people together into neighborly contact…
“We conclude that people continue to act according to the laws of a spatial cluster, even when the block layout and the neighborhood plan do their best to destroy this unit and make it anonymous.
“Gans’ data underscore our intuitions: people want to be part of a neighborly spatial cluster; contact between people sharing such a cluster is a vital function. And this need stands, even when people are able to drive and see friends all over the city.”
Alexander continues to talk about size of the cluster (he believes 8-12 is most ideal, with 12 representing the upper limit as that is the limit of number of people who could meet over a kitchen table and keep in touch with the whole group without too much special effort. He asserts again that the common land is the essential ingredient which “acts as a focus and physically knits the group together.”
Lastly in this pattern, he believes the clusters should not be to constricting or tight – that they should not have absolute boundaries or exclude the cluster from the larger community around it. “Arrange the clusters so that anyone can walk through them, without feeling like a trespasser.”
This pattern is extremely interesting in light of cohousing developments – which are pretty much more deliberate versions of what he is suggesting here. His recommendation of 12 households makes me wonder about the size of cohousing communities – are most of them too large to achieve this natural community that Alexander believes will develop out of house clusters? Is it too many people to keep track of, to maintain good relations with, to not have smaller factions form within the group?
Also, the very nature of cohousing tends to be exclusive. Very, very few communities are so well integrated into their surrounding that someone would not feel like a trespasser upon entering. This creates a feeling of great ownership, safety, and comfort within the community – but does it come with sacrifices that are too great? Is it too suffocating, too cold to the outside world, is it sustainable in the broader sense of being a way everyone in every city or neighborhood could live?
Just some thoughts to ponder, raised by an architect who has enormous insight to the way we actually move, interact, and live.

