I still haven't figured out how to prevent the seekers after a shtf scenario.
It will still be mostly facade. When we talk about "defense" we also include this idea of not making ourselves an inviting target. When considering a place where we shelter, this come in two basic flavors...hard target and undesirable. Hard targets will have distance and normal tactical advantage elements like lights, alarms, dogs, etc. In a SHTF scenario, any engagement is undesirable to say the least and the hard target will likely be viewed as having desirable supplies. So the presentation of the facade should be slanted towards the undesirable.