Is there any way I can compare taking a piece of cardboard (which has air pockets) putting some kind of tin or aluminum foil on each end and using that as insulation with this product?
no sir
the items has to be done correctly .............6 ml mylar one side shinny out ..........then a sealed bubble rap.......then a 2nd 6 ml mylar
to try to make the stuff and seal them together takes alot of room then a set of rollers to apply pressure to attach them all with out weaking or popping the bubble wrap in the middle
if u want a cheaper do it self thing .............u can take the wall down and insulation with stronger stuff the foam stuff will block IR becuase they form those little bubbles inside the foam to make the air barrier
ediit......note this will increase the value of the house ..........u have 2 choices 1 before the drywall goes up u can polywrap your walls then attach the dry then put up a reflective coating of mylar on the inside ............or u can take mylar put it up instead of poly wrap put the drywall up and then paint the room flat white
edit..........one finaly trick i know about IR blocking Tin roof they hate them and they are illegal to build in some states becuase they will aborb the heat from the day making the camera crap they can not see in or passed it becuase of this (my area u are not allowed to use as roofing materals anymore becuase of this only building that orginal had it are allowed to use )