I helped with one a long time ago (just guarding overnight, I was a teenager in a fairly dangerous part of the Bronx... what the hell did I think I was doing???), for a KH that we attended for ~20 years and that was used for longer than that (no idea if it's in use anymore). I don't recall any issues with it until many years later, when they had to tinker with the HVAC.
But it didn't seem like an ambitious project, either. Just a large box with a handful of interior walls and two small restrooms. As long as they didn't skimp on the electrical and plumbing, it was likely to be useful for a very long time.