What should I clad a ceiling with?

[Stuart J]

got a wee basic farm shop, honesty box style, in an old cart shed. Wooden barn doors, one open when shop is open so not 100% protected from the elements.
Ceiling is currently wooden joists with boards above- small loft area above shop.
The aforementioned timber is all tatty and woodwormed so looking to clad over it to tidy it up.
Needs to be moisture resistant and suitable for fitting down lights through.
Any suggestions?

 

[phillipe]

shower boards ,rearo laminates ,glasgow i think

 

[S J H]

I've used pvc shiplap in the past, could probably get a woodgrained one if you prefer.

 

[Nearly]

white hardboard?

 

[TripleSix]

Plasterboard is cheapest.

Shouldn't have problems with moisture unless the roof actually leaks?