house parties work the same way in Ireland as they do in America.
there is a lot of beer, booze, and the ever-present "Mystery Punch." things get broken, and there are white Christmas lights strung up across the ceiling that provide just enough light to make everyone look good. there is plenty of comfortable seating and more things get broken. people you have never met before and will possibly never see again will tell you things they might not even tell their therapist.
and of course, the late-night snack-and-cigarette run. heh. it was fun.