Beam System vs. connecting wood trusses to roof deck

[bill]

Can anyone tell us how to connect wood trusses to the roof? We can create a beam system with a wx girder beam and wx beams perpendicular to the girder beam. When we add various slopes to the roof deck, the wx system is attached to and follows all of the roof height adjustments. However, we cannot figure out how to get wood trusses to act the same way and attach to/follow adjusted roof heights. Any ideas?

[bill]

I would also like to know how this is done! I can create a plane, insert a girder, and if follows the height below the roof deck (reference plane). However, I cannot figure our how to get a wood truss (purlin) to attach to the same reference plan and follow the slope of the roof. The only thing I can associate it with is a level. I cannot figure out how to slope the truss or assign different heights at each end. Please advise.

[Alfredo_Medina]

About roofs and beam systems, follow this logic: If A is aligned to B and B is aligned to C, then A is aligned to C. 

If the slope of A (the roof) changes, the slope of the other two systems, B (girders) and C (trusses), will change accordingly.

See illustration.

[bill]

Hello Alfredo,

Yes, I've seen this solution before. It works great when installing girder beams or I beams in Revit 2009. However, when I try to do the same with wood trusses, they automatically attach themselves to a level, not a work plane. Also, once in the model, you cannot adjust the heights at the ends of the truss, so it remains horizontal. Have you tried installing sloped trusses?

[Alfredo_Medina]

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@BIll wrote:

.... Have you tried installing sloped trusses?

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Yes, from a 3d view, use Work plane > Set and select the sloped bottom face of the roof. Now use the cube to get a floor plan view. Insert the truss. Then adjust the truss´s instance properties for bottom, top, offset, etc.