Chrillsims3 

Dont you know how to make "half splitted" walls or other things with walls? here are some links that will help you.

• Creating New Walls by joninmobile
• Half Walls and Folded Stairs in a Modern House by Amiao103
• Split levelling 4-level house without warped walls by ellacharm3d
• How to Create Split Levels With and Without Warped Walls by Qbuilderz
• Using Foundations as Exterior Walls by exdemon1120
• Angled Columns and Walls by Freynas
• Creating a fake half-wall by Angelamveliza
• Retaining Walls by TheSimSupply
• Half-Wall tutorial by SimsAustria