This picture summarizes most of what I used; the other item is rigid pink foam insulation in 8 ft. by 2 ft by 1 inch thick sheets, source Home Depot.  “Trim coil” is the term used for this thin aluminum, it is sold primarily for encasing sills and other woodwork when installing vinyl siding.  I have seen similar material in vinyl, but it was a couple of dollars more expensive the last time I saw it at Home Depot.

Vinyl might be a little safer to work with.

























I don’t have receipts and prices handy, they can probably be found on the Home Depot or Lowes web site.