Air/bulkwater barrier = rockwool + gps ?
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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I was looking at using delta stratus on my Rhode Island home. How did it turn out?
Unfortunately, we have not moved forward, so cannot comment. But I found a link showing that Dr John Straube used Delta Vent SA on his personal house.
https://deltaacademy.dorken.com/pros-know-dr-john-straube-chooses-airtight-vapor-permeable-barrier/
Because he is an engineer specializing in high performance buildings, I am guessing the Delta Vent (and by extension, Delta Stratus) must be good. I read the product lit for Delta Vent and Delta Stratus: it seems the only difference is the later can be exposed to UV for longer periods without degrading. A sales rep for the manufacturer confirmed verbally this is the only difference.
We want very much to move forward on our project but have not been able to because we have not found anyone willing to do the work we need done, which involves multiple trades working in synch. We have offered to pay someone to provide a detailed quote but no one is interested.
Hopefully your job is less complex than ours. I wish you the best.