What is this?

Sure looks like delam to me.

I wouldn't touch it.

since it's close I'd go look at it to rule out an imperfection in the photo.

The compartment doors on my motorhome are made with two pieces of FRP with Styrofoam in between. There is no adhesive bonding them together. They look very similar to what is in your picture and varies with the heat/cold.

I know this because I damaged one of the doors and had it apart to repair.

Now, if it were the side panels, I would look elsewhere.

Just saw one today that looked like that. Beauty is in the eyes of the beholder. It was just the glue letting go.

Get a pro inspection to be sure.

As Wolfe state delaminated. Had it happen on our when first purchase, Very costly to replace when new. Warranty did pay for it.

Run, Forrest, run!

Bill.Satellite wrote:
Run, Forrest, run!

This!

Ron, our door panels are sheet medal on the outside, either steel or aluminum. Wind caught the edge of the one over the sewer connection bin, and folded it back over 90 degrees. Thought it was going to have to be replaced and painted, but our RV tech was able to take it off and gently unfold it. Amazing that unless you know exactly where it is, you can find no trace of the damage.