How do I seal holes in ZIP sheathing from SIP screws? – GreenBuildingAdvisor

I’m building a house in Seattle area. Sheathing is airgapped rainscreen o/ 1.5″ polyiso o/ Zip sheathing. My “official” WRB in this stackup is the Zip, although due to the rainscreen and taped polyiso this should be a secondary or tertiary WRB. Still there will be entry paths around openings where caulking or tape workmanship is the onlything keeping water from getting to it.

My question: the polyiso is attached by screwing furring strips through the CI and sheathing into the studs. However this creates thousands of holes in the Zip that I cannot access. Some things I’ve considered:

1) Lay down butyl joist tape over ZIP at the studs so the fasteners self-seal at the WRB. Expensive, laborious, and error-prone.

2) Predrill-n-fill screw holes with caulk. Less expensive and laborious but still a lot of extra work.

3) Do 1 or 2, but only under openings 

4) Don’t worry about it, the water needs to get behind 2 planes to even get to these penetrations and the wall is designed to dry to the interior. The Dude abides.

I’m leaning toward #4 but it does make me second guess why I’m paying extra for Zip instead of CDX if I don’t think it’s that important to have the WRB it provides.

I’m not a contractor so I don’t know how much I should worry about this. Any expert opinions?