Flat Roof changed to Sloped Roof

I am working in Revit Structure 2009. I had a flat roof consisting of joist beam systems bearing on steel beams on columns. Now I need to change the flat structure to be sloped. I went and added a reference plane for the slope I want, but when I select the beam system it does not give me the option to set the work plane to the new reference plane. I can draw a new beam system and attach it to the reference plane no problem. Is there a way around this??

Also, all the beams and cols need to move down also due to the new slope. Is it possible to attach them to the reference plane since they are not actually sloped. It would suck to have to create new levels for each side of each roof.

Thanks in advance.

http://www.cadclips.com/Revit-Structure.asp
look at the link above and look at lesson 14 i think it explains what you are looking for.
if you have your beams bearing on walls it won't work (at least it didn't for me) i had to changed them manually.
good luck

I'm finding the same issue. When we do an initial layout for a design developement set the slopes (t/steel) are often not a concern. We're on structure 2010. If the system is supported by columns I've found the following procedure works:

1. Select the column in a section showing the top of column and the reference plane for the slope. In 2010 a button pops up for "attach". Select this and pick the desired reference plane in the section.

2. Right click the beam(s) that attach to this column and select "detach from plane". In a 3D view drag the end points of the beam(s) to the top of the column(s). The beam system should follow the support beam to the slope.

A few notes:

-multiple columns can be selected and "attached" to the reference plane.
-this doesn't seem to work for columns taller than one story as the beam ends can't be snapped to the intersection of the reference plane and the column centerline.
-I haven't figured out how to slope beam systems when bearing walls are used for the boundary.

Hope that's understandable and helps. Would love to hear how to make this process easier.