Choice of materials for vent in storage shed

[Stellan Svealand]

Old water damage near a vent in an unheated storage building. The craftsman suggests drywall. Is it a good choice considering the vent and any moisture that might enter there?

 

[Intet]

Is it just humid air that caused it? No leakage?

 

[Stellan Svealand]

Is it only humid air that caused it, no leakage?

I think it's an old water damage from a downpipe that got blocked by leaves, but that's just my guess. It was already there when I bought the house.

 

[Intet]

I can imagine that. In that case, plaster should probably work fine.