High performance homes require a different kind of thinking for HVAC systems. The loads are often so low that it is hard to find equipment that will provide comfort at decent efficiencies. We'll look at the options and pro's and cons for various approaches, and look at how these choices are determined by the enclosure efficiency, the layout of the home, the climate, the budget, available fuels, the owners' energy and environmental goals, and by any particular needs for climate control inside the building.