1 aerial should be plenty, but I'd imagine you may need a booster or two......when I used to live at home, we had a second aerial put up for my brother and I, that with 1 small booster would serve 3 TVs (21" TV in my room, 21" TV in my brother's room, little 14" portable upstairs) with crystal-clear pic (my dad got jealous, in fact, because our picture was better than his ).