Flashing a triangular gable prior to cement siding install
I'm in the process of rebuilding the front face of my townhome due to termite damage. I've rebuilt the exterior, installed plywood sheathing and wrapped the house with Tyvek. Prior to the rebuild, I had aluminum siding on the house and J-channel flashing/aluminum coil stock that trimmed over the triangular gables (or pediments) over the entry door and window. Due to woodrot, I've had to rebuild the triangular gables. In addition, I plan to install cement siding (7 " reveal) on the townhome. My question is what would be the appropriate flashing method over the triangular gables with hardiplank installed? The tops of the gables are made of 2x6's and will be nailed directly to the sheathing and into the headers over the door and window. I've looked at the white vinyl Duraflash as a flashing option, but have seen a number of negative comments on the breadown of the vinyl materials. Any advice on this material would be appreciated. Would a 90 degree break in a 12" wide piece of galvanized flashing be required to extend all the way over the 2x6's or would a new j channel added at the interface to the hardiplank be sufficient? Thanks in advance for any recommendations.
If the pediment projects out the much I would flash it traditionally. A 4" lip nailed to the sheathing, a 90 degree bend to cover the flat pediment top and another 90 degree bend so the flashing drops down about a 1/2" over the face of the pediment with a slight kickout to shed water away from the wood.