Methods to add 2x material to deepen rafter bays for insulation
I need to add a 2×6 edge edge to my current 2×6 rafters to accommodate r-38 or better insulation in my attic ceiling that will be finished with sheetrock after insulation.
There are a myriad of ways to do this from what I see and my question is around a good fastening methods. The best I like is to glue, toe nail and add 1/2 wooden gussets every 16 inches side to side on existing rafter however I dont like the gusset thickness as Im installing board t board air vents 2/5 inches off the roof sheathing and would have to cut around each gusset.
Glue edge, toe nail and use a Strong tie splice nail plate or thick strap every 16 inchs side to side (easier to add rigid foam air vent material)
Lay the new 2×6 perpendicular to the existing 2×6, and secure with a strong tie hurricane tie both sides and space 2×6 every 16 inches. The metal ties seem like a good idea for less wood splitting than a toe nail although more work and maybe better rigidity (know they are good for lift prevention but dont now about twist)
Anyway, open for ideas on any of this but particularly the use of metal straps, ties etc.
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