What to use for attic access hole in closet ceiling?

[Vier 0]

I enlarged the attic scuttle hole in my bedroom closet ceiling for better access and now have an irregular 18x22 inch opening. Want a clean cover that’s insulated if possible. Ideas?
 

[Szymon 0]

Standard attic access usually gets a purpose-built panel, but for non-standard sizes a large plastic one works well and can have insulation added behind it. This wall hole cover (check bigger variants) is lightweight for ceiling use and strong enough to support its own weight. Many DIYers glue rigid foam to the back for insulation. Looks finished once painted and removes easily when you need to get up there.