In the schedules you can get the gross, net and conditional areas of a wall (inside and outside).
Have a look in the reference guide at page 1742 onwards for wall listing parameters.
Just to complicate things a bit more there are element schedules and surface schedules which are a bit different.
The first image you show is to do with surface schedules and a problem that happens if you trim the zone with an SEO - I don't think it is referring to trimming the wall.
Barry.
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