Do you have any modelling suggestions for internal ducts and service voids or do we just include them in an adjacent zone?
If small, ignore, if large treat them as unconditioned zones if they go the full height. 130 Is there a work around for coffer ceilings that is an extra 300mm raised section in the middle of a flat ceiling. Work out the ceiling area and change the slope of the ceiling to match. If the vertical sides are uninsulated then you must work out the equivalent R value using the tool provided.