Hi all. We’re residing our house and trying to decide between Tyvek HomeWrap and DrainWrap. DrainWrap seems appealing because of its textured surface — the embedded glass fibers create small drainage channels that promote drying.

But here’s the complication: our original tongue-and-groove sheathing has ~1/8” gaps between boards. If any water gets behind the wrap, there’s a real risk it’ll seep through those gaps and soak the wall cavity insulation.

Would we be better off applying the house wrap over the continuous exterior insulation (XPS) instead of directly on the wood sheathing? That way we might stop bulk water before it even reaches those sheathing gaps.

I realize taped XPS is vapor impermeable, so it would trap any moisture trying to escape from the inside — not ideal either.

I also looked into ZIP System R-Sheathing to simplify all this, and the material costs aren’t that far off considering the multiple fastener schedules of the wrap, foam, and furring. But needing to drive individual 4” screws or nails to hit studs through the ZIP-R, existing sheathing, and insulation makes labor costs skyrocket — so that’s probably off the table.

Curious how others would approach this. What’s the better play here — apply wrap on the sheathing or on the XPS? And if you’ve faced similar sheathing gap issues, how did you handle moisture risk?

Thanks in advance!