The rating system describes doing Manual D and Manual J calculations. A full, by-the-book Manual D approach is almost unheard of in residential construction and most homes would fail it if this is the requirement. My read on it is that room-by-room Manual J calculations are required and a Manual D type approach is recommended. Is this correct? A Manual D calc requires a lot of data for blower fan curves, filter and coil pressure drops, detailed duct layout with all fittings specifically identified, etc.