Last year before we finished our basement, I noticed some icing around the outside of our cold air intake. Granted it was below 0 degrees for about 5 days in a row. My contractor put some more fiber glass insulation around it by the basement sill and said it should be OK. He then put the drywall up for the basement ceiling. The cold air intake is just below my living room window. I noticed frost on the drywall at the bottom of the window, on the side of the cold air intake. My contractor came out, drilled a few holes in the wall under the window and sprayed foam. No more frost was seen. Winter is near. I am concerned about this. I am thinking about taking off the siding around the outside cold air intake and drilling holes around it. I want to then spray as much foam in there as it will allow me to around it. Does this make sense? I would rather do that now vs. winter time. Do you suggest I cut a hole in the basement ceiling drywall for access and approach it that way? Any suggestions are appreciated.