Which exterior sheathing is better?
Lizzieplants
| Posted in Green Building Techniques on
Which exterior sheathing system would you recommend – Zip system with housewrap vs plywood with 3M 8067 tape and housewrap? The difference in cost is only $300. We are in Zone 5a, upstate NY. We are concerned about the long term life of the sheathing and what would happen if it gets wet (mold).
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Replies
Elizabeth,
I think the jury is still out on this question. Most building scientists have concluded that plywood is more durable than OSB, however.
Housewrap over Zip? Zip is supposed to eliminate the need for a separate wrap. Either way you sheath the walls, if you also install the siding over a rainscreen gap then you have gone a long way toward rapid removal any wind-driven rain that gets behind the siding, keeping it from contacting the housewrap for any length of time. The siding also will dry faster and hold paint longer than if it is pressed right up against the housewrap.
The plan is to do a rain screen and side the house with Hardiplank siding. We are also looking at a fiberglass siding product called Apex. The housewrap over the Zip is just extra insurance.