Thanks to Pam Hayes-Bohanan for this great article, which is full of geographic lessons. Most important is the great illustration of what geographers call "sense of place." The writer uses the phrase to describe how the physical form and arrangement of triple-decker houses contribute to neighborhood identity in many old mill towns throughout New England.
The article also describes how triple-deckers are particularly vulnerable to the sometimes destructive practices of real estate speculators, by comparing dereliction rates between triple deckers and other kinds of housing. The problem is that triple deckers are inviting targets for speculation. As long as markets are trending upward, such speculators can actually contribute to the rehabilitation of homes and the improvement of neighborhoods. The relatively low cost of the buildings, however, makes them very easy to abandon if markets slacken. When large numbers are abandoned in a short period of time, a neighorhood can quickly spiral downward.
A third interesting bit of geography is the fact that triple deckers could not legally be built today in most places. They are too compact; zoning requires sprawling, low-density residential building. Even the single-family home my family lives in would not be legal today, as it sits on a 0.3-acre lot. This affords me easy access to work, shops, a train station, church, and neighbors -- but it would be illegal to build today. When we started the US-Brazil Consortium on Urban Development (UBCUD), I was fortunate enough to bring James Howard Kunstler to our campus to explain this paradox. He does so very well in his book The Geography of Nowhere.