preferred T&G siding fastener – GreenBuildingAdvisor

Hey folks, 

I’ve got a project that is using 1×6 T&G thermally modified, class A rated hemlock wood siding. I am on the 2021 IRC and the siding is going over 1/2 zip (no exterior insulation, it’s a double stud wall) and a 3/4 rain screen (16″ oc framing). The majority of the siding is going horizontal, with the gable tops going vertical. Climate is high Colorado desert in zone 6b. 

Oddly enough, the siding manufacturer doesn’t have any recommended fastener types or installation guidance. The most they offered is that galvanized won’t react with the wood (like it does with cedar) so I don’t have to use stainless, though “they prefer it”. 

The client prefers a blind nail if possible, but is open to face nailing if required. My blind nailing plan had been to shoot a 7/16″ crown x 2″ leg stainless steel 16g staple through the tongue to get a blind nail finish. However, in reviewing the code, it says that I have to follow the manufacture’s guidelines or nail prescription in 703.3(1) or 703.5.

Based on that, and in the absence of manufacture’s guidelines, it appears that a unless I am going direct to studs, staples are out and I have to go with a 6d >2 1/4″ siding nail…which means no blind nailing. 

However, other T&G siding manufactures say that blind nailing or stapling is fine in 1×6 or smaller so long as there is the minimum of 1 1/2″ penetration into furring strips/sheathing/studs. 

Lastly, screws and hidden fastener clips are out budget/time wise. Blind nail or face nail are the only two options. 

So, the question is: what would you do in this situation and why? 

PS. I doubt the building department will notice either way, as they barely inspect anything. However, I don’t want to install something not to code without some other input to minimize liability. Documentation of your idea would be awesome.

Thanks!