My snake room is warmer than the rest of the house so I can get away with either belly heat or an RHP. The temperature in the rest of the house can swing, and while it's usually just a few degrees cooler than the snake room, in the dead of winter it can drop into the mid-60's if the outside temp goes below 20*F (stupid heat pumps...). So, enclosures not in the snake room have an RHP for ambient temps + under-tank heat for the hot basking spot.