Creating a sloped ceiling using a wedge

1. In 3D View, select the Catalogue tab in the Control Panel. 
   
    
2. Select Generic > Architectural Elements.
   
    
3. Tick the Search box and in the Partcode field and enter Wedge. 
   
    
4. Click Insert unit.
   
    
5. Use the Drag tool to move the wedge against the desired wall.

1. In the Control Panel, select the Layout tab.
   
    
2. Select the wedge.
   
    
3. Under Reference, click the Create / update reference distance line icon.
   
    
4. Left-click on the wall directly to the left of the wedge that the wedge will stretch to. 
   
    
5. In the Control Panel, under the Layout tab and under Size, click the Resize dimensions to reference distance icon.
   
    
6. Repeat this process with the opposite wall using the Create / update reference distance line icon.
   
    
7. In the Control Panel, under the Layout tab and under Size, click the Resize dimensions to reference distance icon.

1. Select the wedge.
   
    
2. Under the Layout tab, under Reference, click the Create / update reference distance line icon.
   
    
3. Reposition the view so that the ceiling is visible.  Left-click the ceiling.
   
    
4. Under Reference, in the measurement field that displays the reference distance, change the value to 0.

With the wedge selected, right-click the wedge and select Create External Surface.