Is it necessary to use a rainscreen when installing fiber cement siding over Zip wall sheathing?
sheacon
| Posted in General Questions on
I am trying to keep the budget down on the siding install on my own home
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Replies
Richard,
As far as I know, neither the building code nor the manufacturer of Zip Sheathing requires a rainscreen gap between fiber-cement siding and Zip System sheathing.
Unless you live in a very dry climate, however, I strongly recommend that you install your siding over a rainscreen gap. To learn more, see All About Rainscreens.
The manufacturer says it's acceptable if you are using "Fiber Cement Vertical, Plank, or Lapped Siding":
http://www.huberwood.com/assets/user/library/Acceptable_Roof_and_Wall_Coverings_v4.pdf
As to whether or not it's a good idea, I'll leave that to those more knowledgable.
A rainscreen housewrap (like Tyvek Drainwrap) might be a good compromise. If you're already going to install housewrap anyway, it won't require any extra labor.