Wall areas are ignored when:

• Enveloping surfaces are entered in a separate drawing file
  or
• Element interaction is set to off
  or
• Priority rating of wall = 0 or <= 3

A = 6.0*6.0 = 36.00 m²

Wall areas are included when:

• Enveloping surfaces are entered in the same drawing file/NDW-format file and
• Element interaction is set to dynamic or static and
• Priority rating of wall > 0 or > 3

A = 6.0*6.0 – 5.0*5.0 + 4.4*4.4 = 30.36 m²