Hardie Panel Over Exterior Mineral Wool Nailing Question
Hi everyone, I’m trying to design the exterior wall detail for a remodel. I’m starting with one wall that needs to be done now, and will eventually get around to the other three. After getting hooked on the FHB Podcast and subscribing to the magazine I want to use advanced materials but I’m getting stuck on siding nail selection and furring sizing. I wanted my wall structure to be as follows:
2×4 existing wood framing
Zip sheathing (new)
1.5” Rockwool comfortboard
Furring strips attached with HeadLok screws
Hardie Panel 5/16” vertical siding panels for board and batten look
I’ve been reading Hardie’s Technical Bulletins about fastening over non-structural materials and this is where I’m getting confused. A lot of their examples specify 1×4 furring strips but their nail charts for 5/16” panels don’t have a fastener under 1.5” in length. They say the fastener cannot penetrate through the furring so 1×4 is out. I considered ripping strips of Advantech into 4” widths as I’ve seen on Matt Risinger’s Build Show (for the durability/weather resistance and straightness of Advantech vs dimensional lumber) but the thickest Advantech is 1-1/8” so I’m still a 1/16” short of my nail length and they only come in 8’ sheets, my wall height is 10’.
So all that leaves is 2×4 dimensional lumber? Which seems to be lot of additional cost plus I’ll have to worry about weatherproofing it since it’s outside my WRB?
Does anyone have any suggestions for furring selection? My head is spinning going from one Technical Bulletin to another. Would it be possible to layer strips of Advantech and offset the joints to 10’ vertical strips and meet my required thickness? Or am I stuck with using 2×4 furring?
Thanks in advance for any help!
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Replies
Im not in this game at all, but will anyone at Hardie TALK to you about it? you cant be first to have this question
I did talk to someone at Hardie technical support, a bit surly but answered my questions. Wasn’t able to give me any guidance about choosing the right furring, just said to “follow your local code.” Basically he said their technical bulletins referred a lot to 1x4 furring for plank installation and not panel. For the Hardie panel the fasteners can’t over penetrate the furring.
He also told me to use 6d 2” nails, although Hardie’s ESR-1844 approves 1.5” .091 ring shank or 4d 1.5” nails for my wind exposure. Although I didn’t have the report in front of me at the time and couldn’t find it in a quick search of Hardie’s site, so I couldn’t cite it back to him. Hardie/Paslode also has Studless Siding Fasteners which are 1-1/8” but those are back ordered with no eta, expensive and there’s the cost of the gun.
So I guess I’m still at a loss as to what to do for furring, my thinking is:
Dimensional lumber and deal with the variance in straightness, weather resistance, and increased cost?
or
Ripped strips of plywood or other WSP? But those max out at 1-1/8”? and I need 1-1/4” to not over penetrate. If I try to layer strips to meet my required thickness how are they fastened and is that even code compliant?
Does anyone have any info on furring that would point me in the right direction?
No, but I’m wondering the same thing. Thank you for posting your question
Over penetration has nothing to do with the furring strips. Hardi doesn't want the nails to over-penetrate the siding.