Before reading mplungjan's answer my immediate thought was musty. I am convinced that his answer fits perfectly Tanninah's need. Nevertheless, I provide alternative answers, which might agree with her more.
- Fetid adj; having a stale nauseating smell, as of decay
[from Latin fētidus, from fētēre to stink; related to fūmus smoke]
- Fetidness n.
(I would not normally associate the smell of staleness and/or mouldy dampness with fetidness. Fetidness conjurs the idea of decay, rankness; an almost over powering smell which would cause the average person to hold back his/her breath. However in Moby thesaurus it is said to be related to musty and fusty.)
- Frowsty adj; Chiefly British
Having a stale smell; musty.
In Merriam-Webster the example they give is: a frowsty, mold-ridden flat in London's East End
- Frowzy adj; Having an unpleasant smell; musty: a frowzy pantry.
- Frowziness n.
- Stuffy adj; Lacking sufficient ventilation; close.
- Stuffiness n.
I still prefer mustiness, though.