How to best attach siding through 1.5″ polyiso?
BillWolpert
| Posted in Green Building Techniques on
With continuous 1.5″ polyiso over 1/2″ plywood sheathing, can I nail wood siding through the insulation to the studs? I was trying to eliminate another layer of plywood. I am planning to use “Hydrogap” by Benjamin Obdyke and not need furring strips.
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Replies
Bill,
I don't recommend installing wood siding over 1.5 inch rigid foam unless you are also willing to install furring strips to create a generous rainscreen gap.
You could install your siding with 3-inch nails through the foam into the studs, I suppose, but it's a bad idea. The siding won't dry evenly after it gets wet in a rainstorm, and it may eventually check, cup, or split.
-- Martin Holladay