I recently came across this article:
I happen to be in CA, in climate zone 3B.
I really like the idea of that system but I wanted to get some feedback on how to do most easily copy a DIY version of that.
The box netting that owens corning provides is pretty neat, it has stable tabs that are used to create different thickness levels of insulation.
I figure if I’m going to do it i’ll go all out and do 12″ of insulation (their drawings show thats R-49, but not sure how accurate that is)
The roof rafters are 2×6’s
The alternative thought was to just use multiple layers of Rockwool (https://www.homedepot.com/p/ROCKWOOL-ComfortBatt-5-1-2-in-x-15-1-4-in-x-47-in-R-23-Fire-Resistant-Stone-Wool-Insulation-12-Bags-RXCB551525/205972546)
I’ved used this stuff elsewhere on the property and I love how easy it is to work with, so I tend to lean towards it over fiberglass.
The first layer between the rafters, the second layer to act as the thermal break beyond the rafters.
Lastly, to more easily attach the “sandwich” to the rafters use a 1″ layer of rigid foam (https://www.homedepot.com/p/Thermasheath-Rmax-Thermasheath-3-1-in-x-4-ft-x-8-ft-R-6-Polyisocyanurate-Rigid-Foam-Insulation-Board-787264/100549260) with long screws.
Anyone got any creative ideas?
GBA Detail Library
A collection of one thousand construction details organized by climate and house part