I’m looking for information on how well fiber-cement siding rides out earthquakes.
Will it crack, pop loose, etc. and how does it compare to other siding materials, especially wood boards?
Also, if it has a tendency to being damaged what’s the relative cost of repair?
Any advice, opinions, first-hand experience and tips on where I can find authoritative information is appreciated.
Scott
Replies
Interesting question. I can't answer it, but I'll be watching to see what the word is.
Seems like it would suffer more than wood, as it is much more brittle. Even a shearwalled section of exterior wall is going to move in a bigger eq, and often there are different stiffnesses in the same wall, where the entire wall isn't spec'd as shear wall.
Anyone else?
k
I know the repair is a PITA if needed. I too think that it'd suffer being more brittle than wood claps. But if its THAT bad of a quake, your siding is probably not the only thing fubar'd.Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
They kill Prophets, for Profits.
to an extent...
but I was in San Francisco in '89, and those buildings were moving in a way which was hard for my brain to accept. And for the most part, the wood framed, wood sided ones kind of went with it, like a dancing hippie on shrooms, all rubbery and loosey goosey, and came through ok.
I'd have loved to see a slow-mo video of the 1 1/2 story house I was renting. I'd guess the roof moved at least a foot back and forth.
I saw a bunch of chimneys down, and some cracked and/or delaminated stucco (although not as much as I would have expected), but remarkably little damage to most of the older wood homes around. Of course, that was only a moderate quake, and centered a ways away, but the movement accepted by the structures was notable.
k
One great thing about fiber cement is that it is fireproof, which may help in an earthquake, and it's flexible enough take the abuse of a quake. If it breaks, then that is probably a small problem in the big scheme.
I would guess awful if the quake is large enough, but I suspect at that time I doubt your siding will be the biggest concern. If you mean say a 5.0 or less, then it would probably perform just fine. Think about how much you can bend it when you handle it. Sure its brittle, but the lateral movement during a small quake is not really all that large. Would it need repairs, most likely, but thats life in a sesimic zone.
Wood will be better since it is not brittle, but then you get to deal with more maintenance.
The focus of building codes and seismic design is to allow the occupants to escape. Building damage is expected. To build structures to prevent building damage during a large quake is not practical as you will eliminate many features and building materials that makes housing affordable. There is a whole host of benefit/cost/statistics studies that go into building codes.
Brad
Again, though, Loma Prieta was a 7. The wood framed and shiplapped sided building I lived in sustained almost no damage. I bet if it'd been fiber cement boards, it'd have been many thousands of dollars of repairs...
Still no verifiable stats, though.
k
I agree, the wood siding will most likely probably perform better. I bet observations such as yours could be the best information available for this type of Q. Post quake reviews generally focus on life threatening issues.
Brad
Although, mine's all anecdotal, and I didn't look at any fiber cement post Loma Prieta. Didn't see too much of it around here in '89.
Stucco actually did better (from what I saw) than I expected, but did have some problems.
Who's got stats? Someone's tested this on a shaker table, somewhere...
k
Very good question, but I'd say that the maintenance, weather tightness, and fire resistance issues outweigh the earthquake factor, especially if you're insured against earthquakes.
Scott.
Almost no one is insured against earthquakes.
k
It's an option here, and we buy it.Scott.
Yeah, it's legally required for insurance companies to offer it here, but almost no one takes it. High rates and deductibles. I'm not saying we shouldn't have it, just that almost no one does.
I doubt many in Ca. have an earthquake policy that would be effective to replace siding. If you had a total loss, sure, but for 10 or 15k, I dunno.
And I took that to be the nature of the OP's question: In a 7.0, where you don't have catastrophic failure, are you going to have thousands and thousands of dollars of damage with hardiesiding that you wouldn't with wood?
I actually don't know.
k
It's a tough call, and one of those things that if most people decline, the rest pay through the nose. We're reconsidering.....Scott.