The room smells of damp.
U-mi-do — three syllables, stress on the first.
Report this to reception — a damp smell indicates moisture or mould and is a legitimate reason to request a different room or dormitory.
'Odore di umido' = smell of damp. 'Umido' = damp/humid. 'La stanza ha' = the room has. Italian hostels in old buildings can suffer from damp, particularly in winter and in coastal cities. A persistent damp smell can affect health and sleep quality.
C'è della muffa in bagno.
There is mould in the bathroom.
Mould is a health concern — report it as a serious issue
L'umidità mi dà fastidio. Posso cambiare stanza?
The damp is bothering me. Can I change rooms?
Assert your right to a comfortable stay
La stanza è ben ventilata?
Is the room well ventilated?
Ask about ventilation as a contributing factor
Italian hostel dormitories on lower floors or in basements of old stone buildings are particularly prone to dampness. Always choose upper floors when possible. If the listing does not specify, ask what floor the dormitory is on before booking — it can make a significant difference to your experience.