noun
roof terrace; roof deck
A flat outdoor area on top of a building, used as a balcony or terrace. Loanword from English 'roof balcony'.
from English roof balcony
このマンションの最上階には広いルーフバルコニーが付いています。
The top floor of this apartment comes with a spacious roof terrace.
ルーフバルコニーでバーベキューを楽しんだ。
We enjoyed a barbecue on the roof deck.