If the other side of an occupied attic is a normal roof space then treat the wall as outside with the approximate properties of the roof.
Model the zone/s on the top level as having external walls of a small height and a raked ceiling except where the dormer windows are in higher external walls.
- An attic should be treated as a normal room/zone with a sloping ceiling/roof combination
- Remember that windows can only be input on external walls
- External walls can be given a smaller height as required, e.g. in the case of dormer windows
- Walls to roof space – See :https://energyinspectionhelp.zendesk.com/hc/en-us/articles/216327517-How-is-an-internal-wall-adjacent-to-roof-space-only-simulated-
NOTE: if there is no vertical external wall height in the attic zones make the external wall 100mm high, but be sure to model the ceiling as raked