Storm cellars make good root cellars. They can be multipurposeTo what degree you prep is where the question can turn to a waste of time IMO. As Annie said above, long as I can drink/eat for a week or and have heat, I'm good. I have a storm cellar these days, I see it as almost a waste of money because at 50 years old I've never needed one but I might. I got it because the builder that built my house offered to put it in over negotiations.