I set all mine on stud walls to be 2.1m high rough, after 25mm floor covering, and 35mm frame and 10mm gap at bottom, there is plenty of room…. To be honest for a standard door i probably made them too tall, but, the remaining gap is nothing that wont be covered with architrave. Door openings is something I should have asked more questions about rather than bumbling through, as it confused me greatly.