In my neighborhood, on one short street, there are two buildings, each built 100 years apart. The first is a three story brick townhouse with a slate mansard roof, simple wooden portico, and stone foundation. It is on a corner lot. It is of precisely made federal style water struck brick. This is a high-quality brick, very dense, absorbs very little water, doesn't expand or contract or spall and therefore lasts. It dates from around the 1860s.
Three or four doors down, there is a square box of an apartment building made with an inexpensive brick, rusting steel relieving angles and tired aluminum frame windows. It is four stories tall with horizontal picture windows placed within a vertical brick panel of a different color, recessed 4 inches to add drama. The roof is flat with aluminum flashing at its parapet. The entry is "protected" by a flat metal canopy supported by thin posts. It dates from the 1960s. It was built at a time when "more is less", which is a euphemism, in this particular building for "less is what you get".
I think you know where I'm going with this, where the older building looks much younger and more refreshed.
Indeed, the townhouse doesn't seem to have had any work done on it at all. It was built well and was built to last. For a long time it was said that you could not build buildings like that anymore, and granted it is a solid masonry wall with no insulation and would be considered, energywise, an inefficient building today. But how much heat is actually lost through a three or four wythe wall with plaster, compared to a veneer brick wall with cheap galvanized steel tiebacks and 2 inches of insulation, when added onto that is the cost of tearing down the newer building and rebuilding it with something that is similar. I don't know the answer to that. Though I can't imagine the cost of heating a brick building like the townhouse is so great that it would be more cost to keep and maintain than to maintain and then replace the cheaper mid-century building.
This just raises the question, what is this sustainability thing? How do we build for the long-haul, energy wise, because my guess is that is the most cost-effective way to go. (Of course, land speculation is going to get in to the way of this).
On university campuses, it's not uncommon for an iconic building to last quite a few years and for it to assume different uses during that period. One that comes to mind is Massachusetts Hall at Harvard University. It was built initially as dorms and has low floor to floor heights. It is very narrow with multiple entries. It seems like a very rigid design not capable of accommodating any other uses but for what it was built, yet it has assumed multiple uses over its 275 year history.
Has there ever been a cost-benefit analysis that has compared two situations such as this? One where the building lasts for many years and assumes many uses and the other were the building is simply torn down after a short period and replaced with something as inexpensive as the first? We should do the research to see just how they compare.