This photo was taken in the attic during a home inspection of a mid 1950’s house. As you can see, energy was cheap back then because the insulation in the attic was minimal at best. They used to use foil battens with a honeycomb inside of foil. When it was snapped open it presented pockets to prevent air flow. It’s still very common to see this insulation present. Of course I recommend that the client upgrade this with some blown-in insulation.  I wonder what future Home Inspectors will think of the insulation we use today…

Attic Insulation uses foil battens with a honeycomb inside of foil