Cornice/Coving/something else?

[Lopéz]

I'm about to refurb my bathroom, and I'm looking for some form of coving or cornice to go around the wall to house the lighting.

It will need to sit about 4 inches below where coving would go on a normal wall.

Any ideas on what I could use? Not averse to using something polystyrene or UPVC if anyone can think of something suitable. Painted MDF would be a last resort really.

 

[Lopéz]

Yep that's what I'm doing, Supercove sounds like it might work, I'd rejected normal coving as I didn't think it would be light enough to stay up with only one she affixed to the wall.