I have been foundation raided and the home point I set in the 15th floor of my base is still there.
If I teleport there I teleport in the air.
I'd also like to know what settings I need to change to prevent people from TP'n back to a "home" after the foundation has been wiped or destroyed. If a person tries to TP back to a "home" and the foundation is gone, I've seen it say "foundation doesn't exist, that home has been removed". Something along those lines, not exactly the verbage.
In response to pookins ():
Well I've been on a server before and once the foundation was removed I could no longer TP there and it was removed from my list. So there is something in the config file that can be set so this happens. Just don't know exactly what it is.