Rob Morley wrote:

Or how about a circular curtain that pulls up to the ceiling when not in
use?

There just might be a way to make one of those work. If you can fix a
low voltage heater in the central tube, hot enough that it boils it dry
when rolled up, it could work and not go all mouldy. What sort of
fabric would tolerate repeated soaking and boiling Ive no idea.
Probably none.

NT