Would it work to put a coating of paraffin over your stored items. I think that is what some people do for food on boats.
You don't really need to on canned goods and using wax on cardboard boxes just makes them a worse fire hazard.I didn't mean sealing canning jars. I had forgotten all about that. That was the way my grandmother did it for jelly and the like. I meant cardboard boxes, canned goods etc.