Attic air Barrier
Hello, I have been hunting around GBA for about two years now and I am planning to build my home in climate zone 5 (CT).
I plan to have a vented attic and place the air barrier (taped plywood or zip systems) above the ceiling joist which will most likely be I-Joists or open web trusses to create a service cavity mainly to install duct work and lighting. I plan to use R60 blown cellulose on top of the plywood attic floor.
The design will be similar to this design https://www.greenbuildingadvisor.com/article/zip-system-panels-as-primary-air-barrier
In order to keep the overall height of the home to a minimum I wish to use a design similar to the picture below with a stick framed roof and a “raised top plate” with plywood between the raised top plate and the top of the I joist. I do not plan to use a ridge beam and wish to use the I-joists and rafter ties.
Does anyone have recommendations on making code compliant connections between all of the components?
In order to maintain R60 in the eves I plan to insulate the the rim joist/attic floor interface with closed cell spray foam to make up for the reduced thickness in this area. Does this seem an efficient approach??
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