I've got an interesting crack in drywall that I'm not sure how to fix. The crack is about 20 feet long in the center of the house where a non-load bearing wall meets a vaulted ceiling. In the center of the crack area is an intersection with a wall corner. I think the crack is caused by movement between the roof trusses and the non-bearing interior walls. There are no good break lines for repainting after the repair so this little crack fix will involve repainting three large rooms.

The home is about 5 years old. The roof is trussed with the outter walls of the house supporting the roof trusses. The trusses are spanning about 48ft. and the crack area is about in the center of the span. The owner kept the truss documentation & house plans which called for the interior non-load walls to be left unattached to the roof trusses. Looking in the attic it appears as though the trusses were "pinned" to the non-load walls with a few nails but not firmly connected like the exterior load bearing walls so there may be some movement. The cracked joints were done with traditional paper tape and mud.
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I want to prevent this crack from coming back in a couple years... Should I try to firmly attach the trusses to the non-load bearing walls? Should I try 3" wide fiberglass joint tape instead of paper or a wider non-woven fiberglass patch sheet?

 

Im not sure about the structural problem you are having. But to fix the crack remove all loose tape and material. Pre fill with quick set mud. Then re tape cracks with paper tape and all purpose mud. Do you have any texture on the ceiling?

 

The ceiling is smooth and once I start I am comitted to painting about 10 gallons so I'd like to get it right the first time.

I know the truss drawing do not say to attach the interior walls to the ceiling, but I am thinking that getting the interior walls to move with the ceiling is the only way to prevent cracks from reappearing in the future.