You can move the roof from elevation view or change the offset value.
Revit roof modify sub elements.
I m not sure if it went away when we installed our new service pack or if it was a revit 2010 thing that i my mind is carrying over or if it s still there but in a new place.
You can use the modify sub elements tool to manipulate one or more of the points or edges on a selected floor or roof.
Click modify floors tabshape editing panelmodify sub elements.
I ve checked the tapered element as the only variable element with a single side defining the slope.
The downside about this method is you can t join the roof to another roof.
Select the floor or roof to modify.
Modify sub elements changing the elevation of newly created point which provides the drainage falls on the flat roof.
You can drag any point in your roof and adjust the roof shape as you want.
You also need to adjust the roof height to match the other roof.
In the example below we add a bunch of points and change their relative height with modify sub elements tool.
At one point in time i recall drawing a roof and then easily placing in roof crickets by clicking on the roof and then going to the modify sub elements portion of the roof modify section.
You might prefer to use the add split line tool which create points at intersections.
In this sample i only use one.
Select the floor or roof to modify.
When you select the modify sub elements tool the options bar will display an elevation edit box in which you can enter a common elevation value for all the selected sub.
You can use the modify sub elements tool to manipulate one or more of the points or edges on a selected floor or roof.
Add a negative value to the middle points and a slope is created.
Activate modify sub elements.
Click modify floors tabshape editing panelmodify sub elements.
You can also restore your completely flat roof by using the reset shape tool which will remove any of the edits that were.