adding a gable roof to a gable roof

[rclement]

treying to do what the book says but i cant get it it seems

maybe one of you revit masters can help me

[barthbradley]

Does this help? Magenta lines are the sketch boundary for this roof.  Note the Define Slope symbols. 

[barthbradley]

[barthbradley]

You could also do this via the Join/Unjoin Roof Tool.

[rclement]

i am doing it that way and i get error

[martijn_pater]

You're one slope short... need one more on the top sketchline in the image you added.

[rclement]

also with the join roof how do i cut the others part

[martijn_pater · Accepted solution]

You can use a void cut or edit the sketch to match.

[barthbradley · Accepted solution]

If you don't want the over-framing condition, then model it the way I showed you initially (e.g. as one monolithic structure) . You can remove that portion of roof after-the-fact, but why bother when you can just create the roof without it from the onset?  

[rclement]

OK GOT IT THIS TIME

[barthbradley]

FWIW @rclement , if you decide to do it as two separate roofs, you can easily modify the main roof's sketch to create the opening by using Pick Lines tool to "trace" the other roof.  Hope that's understandable.