I would call them "Insel" terrace/patio and "Insel" restaurant, respectively

take note of dude's suggestion. is it a terrace or a deck?

n.b. I worry about your translation of this brochure considering the number of queries you posted. Get someone proficient to edit your opus - unless you are doing it just for fun...

Note to #2: Read "someone proficient" as "a native English speaker"

Note to #3: read "someone proficient" as "someone proficient in translation issues [u. selbstverständlich, Muttersprachler]" (but that's already how I read it).

Knowing just when *not* to translate a word and to leave it in the source language to provide some local flavor without obscuring meaning, is a true art, and I thought Dude's proposal inspired. (As his contributions often are.)

Falls sich die Terrasse auf dem Garten befindet: "roof garden"

Falls sie sich auf dem Dach befindet (und nicht im Garten)!

@#6

Stimmt! Da hatte ich bei #5 einen Blackout. Danke für die Korrektur!