When installing  cedar shingles/shakes over SIPS for exterior siding ,if you use building felt over the sip do you also need a rain screen ? What would be the ideal combination. These are individual shingles . Location , north eastern   NC.

Thanks,
Edward

Edward,
The quick answer is yes, you need a rainscreen.
Not for the SIPS, but for the siding.
A rainscreen allows for air movement around and behind the siding. This allows the
wood to dry completely, and more quickly, increasing the lifetime of the wood and the finishes you might
use on it. Make sure that whatever sealant you use is on all sides of the wood. Even minor trim cuts should be touched up before installation.

If you have properly installed felt, that is your rain screen. The generally accepted definition of a rain screen is the continuous barrier behind the siding that drains the bulk water down and away from your wall assembly. Remember, ALL sidings leak. Because you don't want water in your wall assembly,(especially if the assembly is wood)the felt will shield the SIP from the water that gets through your shingles. The function of drying your siding for the sake of longevity is often accomplished by back-ventilating. Some siding is self-ventilating and some absolutely requires back-ventilating. In the areas with wet climates or prolonged periods of cold ,dark, and damp conditions, back-ventilating becomes more important. All wall and roof assemblies need to be detailed to allow and often increase drying potential. The cedar shingle siding should, in my opinion, always be back-ventilated. The product most commonly used for shingle walls is "Cedar Breather". It's made by Benjamin Obdyke and installs in large sheets behind the shingles or shakes. Al Cobb