how do I refer to bathrooms that are completely full / unavailable?

Question

I wanted to say something like "No matter where I go the bathrooms are always all full. Do I use any of these:"満席?いっぱい?全使用中？空いていない？

In which case saying the bathroom is "full" is one way to say it, but how would I also say it conversely with the bathrooms are unavailable (because they are full)

Answer 1

I would say...

あそこのトイレ、いっつもいっぱいで[入]{はい}れない。
昼休みはトイレ混んでて入れない。
トイレ(の個室)、全部使用中。
女子トイレ、一つも空いてない。
女子トイレが[満室]{まんしつ}だったから、男子トイレに入った。