The correct reaction is to douse the building with gasoline and use a military-grade flamethrower to burn it down. Then use a stump grinder to turn the remains into very small pieces of ash, and then cover the whole thing with 98% sulfuric acid.
And then repeat the whole process at least 10 times just in case.
Maybe it's the infantryman in me, but that seems impractical. If you're going to do something, do it right the first time. You know, with spider-eating-spiders.