As an adjunct to the other thread on fallout, some questions: I understand radiation is DIRECTIONAL. Therefore, it seems apparent that just descending into a full basement will solve the bulk of exposure issues. This provided you've shut off all HVAC systems that might still be functioning, taped up the entrance and donned an N95 at minimum. No radiation will come up from the floor, obviously, and all four directions around you are also blocked by earth. The remaining direction is what comes from above. If the house survives a blast some distance away, fallout could still land on the roof and that appears to be the remaining threat. Unaugmented, the radiation has to travel through: Asphalt shingles, the wood roof, 8' of attic airspace, The attic floor/main level ceiling 8' of living level airspace, main level floor/basement ceiling I guess it again falls to type of fissile material and amount of fallout, but if the house survives undamaged otherwise and I don't have time to create overhead barriers, is this survivable, or will the two weeks i spend down there just cook me?

Curling up in a corner of a basement where you have piled up as much mass over and around you will be your best approach, given your alternatives. Everything of course IS based on how much and what type of radiation we are talking (as well as time exposed). With nuclear warfare fallout, we would expect some type of gamma radiation to be our nemesis downwind of ground zero, post-detonation. In the simplest terms, a rule of thumb is that you want to try to have at least this much shielding mass (the more dense, the better) between you and the sources of fallout radiation (this lists a variety of equivalent shields): 1. 5000 feet of air 2. or, 9 feet of lumber/wood 3. or, 6 feet of water 4. or, 3 feet of packed soil/earth 5. or, 2 feet of dense concrete 6. or, 10 inches of steel 7. or, 4 inches of lead 8. or an appropriate combination of the above. Fallout on a one or two story house roof would be the problem in the situation you describe, so again, you want to get as much dense mass over and around you in the lowest section of a corner of a basement, if that is what you are stuck with. Here is short animation to help illustrate various situations: http://safecastle.blogspot.com/2010/12/la-dry-run-shows-urban-nuke-attack.html