We will certainly treat an open concept room differently than we will treat a separate “destination” style of room; we will treat a smaller space differently than a large space; and we will treat an east-facing room with significant tree coverage differently than a west facing one with full sun exposure. Having said this, once the heat gain and heat loss calculations are presented to us by the HVAC engineer, it is up to us to pick the medium that we will then use to meet the prescribed heating and cooling loads. Common methods include, but are not limited to, forced air extension from an existing or new self-contained furnace, a radiant heated floor (electric or hydronic), a gas fireplace and/or split ductless heating/cooling units, etc.