Discovered that the attic access hatch isn’t insulated, which honestly isn’t surprising given when it was built. No ladder system. I’m working on cutting up some foam boards to glue to the backside. Hopefully it will reduce how much is radiated through this barrier.
It would actually be more effective to put the reflective stuff on the under side of the hatch since this would reduce its ability to radiate heat to your space. It would look terrible of course. Actual insulation on the top is going to be the most effective.