Replace equivalent Tretex ceiling

[oscarwww]

A lightweight concrete wall has been removed and now there is a plank on the ceiling covering the "hole."

Is there something nicer that can replace this plank?

 

[tompax]

I had just installed a new fairly thin white-painted "list" to cover it.

It's not easy to get it right otherwise.

Cut a piece of plywood to a suitable thickness, about 10 mm, sand it smooth, fill, sand, bevel or rout the edges with something nice, sand lightly again, prime, sand a bit, and topcoat.

IF there is a ready-made list in an appropriate width, you can use that.