I agree with Gillnetter on the house vs. home distinction, but I think you should use "house" in this context. It may not be precisely accurate--you may be speaking to someone in an apartment--but you don't know the person well enough to know whether this building is the place s/he calls "home." There's an old saying, "home is where the heart is." I've lived on my own in Boston for eight years now, but I still sometimes refer to my parents' house as "home," as in, "I'm going home for Christmas." You don't really need to know whether their true home is a tree house or a lonely vessel out at sea; you just want them to check the phone jacks in the building in which they are currently residing! Use "house."