I plan to use metal tape to tape double reflective insulation (e.g. Reflectix) along the vertical columns, as seen in this reference photo for a Chevy Express utility van. This would create the "air gap" layer that makes this type of insulation effective. Do you all think that is a budget-conscious solution, beyond a ceiling vent fan, to address nights (van mainly used for sleeping) in higher-end 100F summers? Thanks for your input! #lifestyle