The exterior surface is integrally-colored plaster, and fire's just about the only thing that could have damaged it. It's applied with a trowel, so it's more labor-intensive than paint to apply, but—barring immolation—it should last much, much longer, with a depth of surface hat doesn't come through in photographs. (Those beautiful buildings with richly textured walls you admired on your last trip to Europe? That was integral color plaster.)
The green benefits are many: reduced maintenance over time, and plaster is finish and structure in one, so there's less material overall.
The main drawback, aside from the labor involved, is the impossibility of making an invisible patch if a repair is needed. Still, we like buildings with a sense of history, so this isn't a total drawback for us.
Integral color plaster can be used inside, too. We like American Clay Plaster. In many cases, it can be moistened and reworked to blend in patches, which eliminates one of plaster's big drawbacks.