Should feather-edge lap siding be installed directly on sheathing or on furring strips?
It's really a matter of prerogative (which is why you get varied suggestions), but it sounds like you have your answer. You want to be &quot;careful&quot;, which I interpret to mean you're willing to put in the extra expense and effort to get additional longevity. It might last 40 years instead of 30 if you let it breath.
In my experience, lap siding is installed directly over sheathing/house wrap. Wall shingles tend to be installed over strips, but that's because they tend to let more water through all the extra joints. Your mileage may vary.