(remark: unit in UE is by cm)
Project Setting, Engine → Rendering → Disable follow:
In World Setting → untick Compress Lightmap
Place the floor plan in scene, change to top view perspective
Create a Box Brush (in Geometry of Place Actor) → Details → Brush Settings XYZ: all 90
Move Set pivot point of floor plan layer to any door (on x axis): hold Alt+middle mouse to the point, R click on the floor plan, Pivot → Set as Pivot Offset
→
move the box brush to fit the door size, scale up/down of the floor plan
repeat the same, but find a door on y-axis instead
Increase the Box Brush Z value from 90 to 300 (to create height of floor plan)
→
Place the box brush to any 1 of the corner of the floor plan
Activating Brush Editing (top bar) → use Edit to make the customized Pillar → use extrude to extend as a wall
Finish the whole wall structure
9: 20