If you have excluded a folder when you created the archive then there are no contents of that folder in the archive in the first place. So when you extract your files again then there should be nothing that the excluded folder(s) can be overwritten with. And nope, it should not delete any files on the filesystem just because they are not present in the archive. That would be deeply counter-productive and I have never observed such behaviour so far.
Originally Posted by djbon2112
But you could check ... Have tar list the contents, e.g.
.. that should list the contents of the archive and you'd see if anything would be overwritten. So in your case there shouldn't be any files going into /home ... If that's the case then nothing underneath /home should be overwritten or deleted.
tar tzvf backup_filename.tar.gz | more