User blog comment:Joey.eyeball/The Sims Wiki News - 10th November 2014/@comment-4061583-20141110062249/@comment-5385060-20141110123253

Didn't sims 3 already allow windows on pools, from LN. I was sure, that one of the clubs in Bridgeport, the pool had windows on the lower floor, to look into it. I can't check to make sure, because I don't have the expansion pack. My cousin let me play sims on her comp, and LN was one of her expansion packs.

Anyways, getting a tad off topic there. I am also sure, that pools can be put on other floors too, in TS3.