Perhaps a silly question: If I am not mistaken, łazienki is the genitive. Does potrzebujemy always require a genitive object?
It's another case that's not difficult understand in English because you can think of potrzebujemy as meaning "we have need of".
"Dużej" doesnt mean bigger? Or am i making a mistake with some grammatical declination or sr else?
"dużej" is Genitive of "duża".
But you're not totally far, because -ej ending is used for the comparative form of adverbs.