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Note: The way to assign height to a wall is to open its Properties to the 3D page and enter a Height.
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1. Select the Roof Wall Modifier tool.
2. From the Local menu choose eitherĀ
3. Select the wall you want to modify..
4. Select the roof to which you want the wall to extend.
5. The wall will now extend to the roof.
Top/Bottom Wall Modifiers will override Roof Wall Modifiers, and Roof Wall Modifiers will override Top/Bottom Wall Modifiers, depending upon the sequence in which they are added.