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. This would include adding additional insulation to walls if this is present in the roof construction.
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