Alternatives to this Pretty Good Roof Assembly
Looking for opinions. We are working on the design for our pretty good house in central MA and am having some debate about the best way to construct the roof. The house will be a historic looking cape with the goals of R40 walls and R60 roof. Walls will be GWB> 2×6 24″OC w/ cellulose > OSB sheathing > self adhered WRB > ~4″ reclaimed rigid.
For the roof, I am considering 16″ TJI’s, with tyvek or 1/8″ plywood under the top chord to form a ventilation channel, and dense pack cellulose filling the cavity. This would give me close to R60, a 1.5″ ventilation channel and hopefully be cheapish/ easy to install. Exterior rigid seems like it would add labor cost and be a bit more expensive overall.
My question is, is there a better alternative here? As with every project, we are on a tight budget (especially with current material costs). Should we consider parallel chord trusses or something else entirely. (Preliminary exterior design attached)
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