Add a ceiling to the garage based on the exterior walls
Activate the model window by using the File > Switch
Between 2D and 3D function.
The garage walls do not form a continuous closing wall chain.
Select the walls one by one. First, select the interior wall (A) of
the garage.
Select the exterior wall (B) of the garage.
Select the rest of the garage exterior walls by clicking the
Next
wall button on the contextual toolbar. Click the button 3 times
to select the remaining 3 walls.
Select Confirm. The program will add the ceiling.
Quit by pressing the Esc key.
Activate the drawing window by using the File > Switch
Between 2D and 3D function.