Creating Dormer Roof Opening

[Damo]

I'm having some problems trying to create a dormer opening in a roof and am wondering whether I'm missing something very basic (or is there a bug in Revit 8 ). I have been able to do it in the past.

I have a simple pitched roof; I want to create openings for a secondary roof & a dormer roof using the 'Opening' option on the Modelling tab. (Pick a roof to be cut by a dormer opening).

But;
1. I cannot join the roofs. I get an error message "The roof cannot be joined", and then,.....

2. .....when I use the 'Opening' command, although I can select the main roof, I cannot select a joined roof or a joined face of roof to create the opening (because of point 1 above)

Any guidance?

[beegee]

Use the following steps:

Create a model with an attached roof as a dormer and with walls attached to the dormer.

http://www.aac-solutions.cz/img/ext/vikyr1.gif
Go to a plan view where you can see both the dormer and the attached walls.
In the Modelling menu select Opening...
In the resulting dialog box, select 'Pick a roof to be cut by a dormer opening'.
Pick a roof in which you want to make an opening. Revit will switch to the sketch mode and prompts to select the boundaries for the opening. Valid boundaries are - the attached roof, wall faces and model lines. In this case we select the wall faces and the attached roof.

http://www.aac-solutions.cz/img/ext/vikyr2.gif
Select Finish boundary.

[Damo]

Thanks Beegee,

I'm sure there is something very fundamental I'm missing here.

I did manage to draw 2 of the roofs (by doing them in a single process) but I cannot get the other smaller secondary roof built.

Creating a Roof by Footprint, with 3 sloping planes, I get a very non-descriptive error message "Can't make footprint roof."