Roof Deck with Mystery Lines

[troberts]

Can anyone tell me why I sometimes get these lines (see Attachments) at the top and bottom of my roof deck?
I am using RST 2008 both sections are cut perpendicular to the deck and have Far Clip Offset at 1".
Both sections are 3/4" = 1'-0"
Display = Normal
Detail Level = Fine
Model Graphics Style = Hidden Line

[m20roxxers]

Make sure your Decking is set to Bound above Layer in the Structure in the type properties.

Otherwise the line comes up when you have it set to Standalone Deck.

[troberts]

I can't set the Deck Usage to Bound Layer Above. There is no layer above. As a Structural firm we do not model roofing or insulation. I am not sure that that is the problem though, because both examples that I posted are from the same project and they both have the usage set to the default Standalone Deck.

[Andre Carvalho]

I notice in one of your examples the roof appears to be flat and the deck is shown correct. The wrong one appears to be sloping and the decking is showing with those lines. I have never seen this before, but do you have on this project any other sloping roof with the deck showing correct? I know roofs are meant to be flat or sloped, but if it only happens on sloped roofs, it might be a bug in your file.

Andre Carvalho

[troberts]

Andre,
I started a new project and the roof deck looked fine, until I sloped the deck!
As soon as I sloped the deck the lines appeared. The lines appear no matter which way I slope the deck. Any ideas?

UPDATE:
Okay I tried sloping the deck using the slope arrows instead of the Split lines and the Sub-Element Points. Doing that the top and bottom lines don't show up. Slope arrows might work okay, if each roof area is a flat plane; but my roof has some warped planes.

[Andre Carvalho]

I'm sorry I don't have Revit Structure in front of me right now. However, I have a floor with deck (brought from Revit Structure) that shows fine in RAC even when sloping. Have you tried using the same profile on a floor and trying to slope it in Revit Structure? If it works, then maybe the sloping problem only occurs with roofs and may be a bug. And if that's the case, filling a support request and sending it to Autodesk is the best thing to do.

Andre Carvalho

EDIT: Just read your message above. My floor was also created using slope arrows and not using sub elements.