One of the reasons I like the notion of colonizing the atmosphere of Venus, (Come on, admit it. When you live in a floating castle, the notion doesn't seem that strange.), is that additional room can be woven out of the air.
That's right. All the necessary ingredients are just floating around. You'll need a little chemical mastery, but hey, it took rocket science to get you there in the first place, right?
So in your spare time, you knit yourself a spare room.
You’ve just got it all sewn up, haven’t you?