Air / bulkwater barrier = rockwool + gps ?
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Zone 6, wet and cold (NH). Is this a continuous air and water barrier for walls? wood sheathing, then delta stratus fully adhered wrb, then 3 inches of comfortboard 80 (rockwool) then 1 inch of gps. Tape gps panels at all seams. Then 3/4 inch vertical furrings with 3/4 inch thick gps between each furring. Then vinyl siding. I know gps panels (assuming taped at seams) serve as a continuous air and water barrier. But would the assembly still be airtight and watertight if there is comfortboard 80 inward of gps? I need 4 inches rigid insulation outside of sheathing. Trying to think what materials would be least permeable to bulk water and air while staying most permeable to vapor. Thanks
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