As plans for the healthcare wing expansion become more concrete, Kendal residents will be asked to consider a significant increase in our independent living (IL) population as a mechanism for raising part of the money for it. This approach has been successful at funding new building projects in the past, but it ultimately depends on an ever-growing IL population.

Kendal’s IL population (300+ residents) is currently higher than it has ever been. Is that a problem? Would increasing it another 10% be a problem? Might Kendal’s quality of life be damaged by a population increase, or would it be improved?

My sense is that Kendal is already big enough—and perhaps it might even be bigger than its ideal size. But my gut feel is not a useful basis for a discussion with others about optimal size, so I set out to see if there was research about community size that could shed light on the question.

I hoped I might find research on the impact of the size of retirement communities on the quality of life of the residents, but I didn’t find anything of that kind. (If you know of anything, please let me know.) What I did find was a wide variety of related studies that may have relevance for us. The studies fall loosely into three categories: studies of residential communities, studies of on-line communities, and studies of friendship.

Size of residential communities. For about the last 30 years, researchers have studied the success of intentional residential communities of various types and sizes. The leading researcher on this topic, Robin Dunbar of Oxford University, has written several books about this. A good summary of his work is here. A comprehensive scientific paper reviewing Dunbar’s own and related work is here.

Dunbar’s examples are drawn from all sorts of communities.

Examples of religious communities include the Hutterites (who always split off a new community when an existing one exceeds about 150 members), the Amish (who think a community is getting too big when everyone doesn’t know everyone else by name), and the Bruderhof/Society of Brothers (160 to 300 adults, max).

A study of 19th-century utopian communities showed that the ones that lasted longest generally had around 150 adult members at the time of founding.

Israeli kibbutzim (which may be religious or secular) are predominantly 300 residents, plus or minus 100 or so. The larger kibbutzim (especially the secular ones) tend to lose residents.  

Dunbar cites dozens of related studies, so it is clear that this is a research rabbit hole one could go down for a long time before re-emerging. I didn’t do that. But based on what I did read, I conclude that many residential communities perform best when they have 150-300 residents. They can lose some of their internal cohesion as they increase beyond that size.

Size of on-line communities. It might seem unlikely that studies of on-line communities would have any relevance for a residential community such as ours. But in fact, on-line relationships, especially daily or weekly ones, have a lot in common with the in-person relationships we have here at Kendal. There are  lots of studies of on-line communities. It is much easier to collect statistics for them than for in-person ones.

Researchers have found that if an on-line community requires frequent and significant participation, it will periodically gain and lose members, but probably won’t grow beyond about 200 members. For example, that’s true of the volunteer administrators who run the Wikipedia.

As Richard Millington explains: “Beyond a certain level of activity and a certain number of members it becomes difficult for all members to believe they can influence the community…. Past a certain number of active members in a community, it becomes impossible for a high level of familiarity to persist. Members will know fewer and fewer of the participating members.

Therefore, the overall sense of community in the community begins to decrease. This often leads to less ownership over the community and eventually a lower number of participating members.”

I submit that these observations about on-line communities can also apply to a retirement community such as ours. I see signs of residents doubting their ability to influence the community, and signs that the sense of community ownership is declining. And I find that, after three years, there are still many people at Kendal who I just don’t know—and some that I probably never will.

Friendship studies. A final helpful area of research is the investigation of friend networks. Again, there is a wide variety of material on this topic—another internet rabbit hole. Christopher Allen has done a nice of summarizing some of this material here.

Allen lays out four categories of friendship and their characteristic sizes.

  • The Support Circle (3-5 people): “This is the number of individuals that you seek advice, support, or help from in times of severe emotional or financial stress.”
  • The Sympathy Circle (10-15 people): “This is … the number of people that you go to for sympathy and also those people whose death would be devastating to you.”
  • The Trust Circle (40-200 people, but generally less than 150): “These are the people that you have some type of intimate connection to.”
  • The Emotional Circle (close to 300 people): “… the total number of people that you can have some type of non-mutual emotional connection with, most likely spread across numerous groups of all sorts.”

If you think about all the names in your address book, you can probably place each of them in one of these “circles”.

These groupings, or very similar ones, show up in many lines of research. This suggests, among other things, that it is nearly impossible to have a real connection with more than about 300 people.

Signs of size effects at Kendal. At Kendal, we are at about 410 residents (including IL, Personal Care and Skilled Nursing). That means we have passed the size at which any resident could have every other resident in their “emotional circle”. The question then becomes: does our quality of life suffer because of our population? Would adding more people make the situation worse? At what size do we say, “this is big enough, no more”?

I believe Kendal has begun showing signs of being somewhat too large. The research on size in voluntary communities shows that people leave (or whole groups of people split off) when the community gets too large. These are not options at Kendal, of course. But there are some signs of schism, and of breaking off into competing clusters.

Have you ever heard hushed complaints like these?

  • “Those Quakers. They seem to think they own the place.”
  • “Those people in the duplexes. They seem to live in a separate world from the rest of us.”
  • “Those KRA people. They seem to give their friends all the best committee spots.”  

I take these “us vs. them” comments as an indication that perhaps we don’t know each other well enough. And if so, that’s at least partly due to the size of our community.

I conclude that the size of our community may already be having a negative effect (admittedly a mild one) on our quality of life. I would not like to see Kendal grow any larger.