ideas for insulating garage/wall ceiling covering

My shop is a pole barn, so it has 2x6 purlins for the walls. I cut regular R33 insulation for each space in the walls and covered that in plywood so it would not get destroyed if I bumped into it. That was a really good decision. For the upper walls and ceilings, I called in some insulation guys who knocked it out in a day and a half, some of the best money I ever spent on the shop. It was about $2300 to do the uppers you see in white. They covered it in some kind of sturdy white sheet material that really helps reflect light and made the shop a LOT brighter. Here are before and after photos.

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