I got the magnetic tape at a local hardware store, so it shouldnt be
hard to find. I recessed the channel exactly the thickness of the
board. I have 2 pieces of foamboard glued together, one is larger and
overlaps the brick outside in front , this is the only way I could
figure to get an airtight seal. So I have an R 20 plug that helps alot ,
the room is warmer.