The case against underfloor air conditioning

As you raise insulation performance, at some point "indoor heat generation" and "heat loss to the outside" come into balance. The point a Passive House aims for is exactly this. Once you're at that level, underfloor heating can become a burden — causing overheating and excessive dryness. And a wood-burning fireplace becomes nothing more than a luxurious interior fixture that compromises airtightness.