A day after a brief but violent storm knocked out power and downed power lines across mid-Michigan, I was greeted with pictures on Facebook from friends in St. Louis who posted pictures of widespread destruction of historic buildings that had lost whole roofs. Our neighborhood on the west side of Lansing fared alright, but the river trail I take to work at Michigan State University saw a bunch of downed trees and debris. We know that storms are getting stronger and more unpredictable, which is easily explained by a few basic elements of climate science. Doesn’t that mean we should be spending more time and money figuring out how to make infrastructure stronger and more able to withstand these extreme weather events? Should we not spend a lot of time also on our buildings, to make them more resisilent? Let’s take a look at each question.
Shoutout to Martin Casas, whose photos of storm destruction I’m borrowing from a public Facebook post.
Why Might Old Buildings Be Vulnerable?
While wearing my construction hat, I often hear historic preservationists wax poetic about how “they shore don’t building buildings like they used-ta!” It’s kind of true. But when disaster strikes, we are reminded of how sometimes older buildings are, in fact, built much worse than some newer buildings.
It’s not as simple as saying that “old=good” or “new=bad.” We know, for example, that old buildings have some unique thermal parameters– especially St. Louis brick buildings, which have thick walls that keep buildings relatively cool in the warmer summer months (at least until a heat wave hits, and then that brick is potentially still radiating heat all night). Sometimes, old isn’t great.
But as far as how they were built structurally, with respect to wind loads? These calculations were minimal in the extremely limited to nonexistent building codes of the 1900s, when much of St. Louis’ building stock was built.
Modern roofs involve rafter framing that is attached to the “top” of the structure– in lay terms, where the boxy, framed part of the second or third floor meets the slopy part of the roof- using sturdy, steel bits. These allow for wind shear that doesn’t do what we see in Martin Casas’ photos above. In days of yore, the rafters sometimes just sat on top of the sill plates, with little more than something like a notch or a toe-nail. This means that extreme winds can quite literally lift the entire roof off, which is some of what we saw in St. Louis.
Shear resistance is also higher on new buildings because of how framing attaches sheathing to framing. Old buildings often used some sort of cross-stabilizing elements like ship-lap siding that was then anchored to brick walls, and it’s a testament to how well-built the load-bearing walls were in some of these houses that they are still standing, even if the roofs have been ripped off. Ultimately, load paths were well understood as an engineering concept when most of these buildings were built, but the ways to protect against extreme weather, not so much.
It’s not all shiny on new buildings, even if they have straps that can hold the roof on. California wildfires, for example, showed that materials like tile roofs and cementboard siding hold up far better to the extreme heat of wildfires compared to, say, vinyl siding on newer houses that melts into toxic sludge.
Can old buildings be fixed?
Short answer? Yes. Long answer? In St. Louis, many of these buildings will be demolished, tragically. Many that were wrecked did not have insurance. Rebuilding them with insurance claims will be possible, but will take years. I imagine insurance companies are shitting themselves, too, trying to figure out how on earth they’re going to come up with the millions of dollars of repairs required for these buildings while still delivering a profitable bottom line. (This question dogs the industry these days as the market grapples with how to deal with climate change).
If you did have insurance, you will, we must imagine, receive a rebuilt roof that is built to modern code standards. This could cost $30,000, or it could cost a quarter million, for a 1900s house built with solid masonry that has suffered damage from losing an entire roof and the subsequent damage from exposure to the elements.
Building back better, more broadly, though? It’s possible, but it costs money. It’s unlikely to happen in a broke city that is on financial life support, in a state that would rather write bills stripping democratic agency from the electorate and inspect children’s genitals than fund climate resilience.
What about utility Infrastructure?
Every time a storm like this happens, someone always asks why we can’t just put the power lines underground. It is, unsurprisingly, a very simple answer: cost.
Utility companies have long argued that we cannot afford the high cost of undergrounding power lines. It’s true that it’s very expensive. But what’s also expensive is how much money we spend each year on disaster recovery, and that number is only expected to grow. As I remind my students all the time, this growth is not evidenced by the “number of billion-dollar disasters each year,” a nebulous metric. This tells us nothing about climate change. It just tells us that people are building more stuff, and probably more stuff in more disaster-prone areas. It goes back to my Masked Man scenario.
Utility nerds will tell you that there are other reasons why we don’t underground utilities– the fact that it’s far more expensive to upgrade local capacity later. I have a way around that, and it involves planning for future capacity. Most of the cost associated with building infrastructure comes from the cost of digging up the ground and repaving the street (remember my quest for “Dig Once”?). We can project near-term growth relatively reliably. We can also futureproof by installing additional capacity in case we need to.
Sure, it’s expensive to spend money to build more storm-resilient buildings and infrastructure. But what else is expensive, as I mention in the article linked earlier here? Not spending on these things.
See St. Louis Public Library for tornado relief resources. Photo credits to Martin Casas, once again.