Never at my parent's house, too many people, not enough room, no privacy.
With my first sexual girlfriend we fucked at my place most of the time, when she still lived with her parents. We fucked a few times when her parents weren't home, but one evening we got so horny that I started fingering her while watching TV a few feet away from her parents who were on the other side of a louvered door in the kitchen. I was hard as a rock as well, but we had a blanket over us, so when her mom popped in to offer us food/drink, we simply paused until she left the room.
Neither of us came, as her parents were so close by and were were too nervous. But when they went to bed, and we were sure they were asleep, I went down on her and she came in about 1 minute! She immediately pulled me into her and I fucked her silly.
A similar question came up before about having sex when staying over at friends or families homes when visiting. The answer in those circumstances is 99% of the time, yes!