Basement attached to crawl space
Last year we added a sunroom with a basement beneath it for storage and for safety during tornado weather. The remainder of our home has a crawl space only. We were told that a 3 foot space had to be left between the crawl space wall and the basement wall to allow for setting and removing forms. They did not backfill the area and the contractor did not close off the wall/ceiling. I have found that the dampness/odor coming into the basement is very offensive and worry about mold and insects/snakes/mice getting into the basement and up into the sunroom. The basement is an unheated area with only a sump pump. Other than adding a dehumidifier, are there any recommendations for closing off that area.