Cross battens vs 3d mesh – standing seam (or, shingles) – GreenBuildingAdvisor

Hi All,

Does anyone have opinions, experience, or data regarding the pros/cons of putting a cross-batten grid of ~a few inches, vs. a much tighter ‘air gap’ using a product like Keene’s Viper Vent: https://keenebuilding.com/products/viper-cdr-vent/

In my situation in CZ3b (also high risk fire zone), re-roofing over both an unvented cathedral and vented attic, looking at options that would allow interior humidity/moisture to exit above the roof decking, ostensibly with a vapor-open underlayment on the whole house. It would be slick to be able to use the Keene product, since without the added height factor of battens, I could keep gutters, fascia, etc nearly the same as they were with a shingle roof. I am hoping to use mineral wool insulation inside the unvented cathedral, and looking for a safe moisture control system. (Sadly, exterior rigid foam or a VDP are looking to be impossible in my case, hoping to avoid ccSPF).

Cheers!