Nails for LP Smartside on Rainscreen
Salesi| Posted inGeneral Questionson
Has anyone installed LP smartside on 3/4 furring strips on exterior foam insulation? We are getting ready to side our house and I know LP smartside list on their website that an alternate is to use a 2 x 4 for the furring strip. However I do not want to use a 2 x 4. Has anyone used 3/4 furring strips for LP Smartside, if so what type and size of nail did you use? Any issue with wind or anything else? I know it will void the warranty.
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My most recent use of LP Smartside was an entire house of 3/4" pine firring strips secured with screws through 3" continuous exterior foam and sheathing and into studs. I used collated clipped-head 2'' or 2.375" ring shank nails, all concealed nailing except at rakes and certain other awkward situations. Stainless steel not necessary, IMO. Works like a charm, no wind (at least nothing short of a tornado) is going to yank these out, even from the dubious quality of #2 graded strips. IIRC, there is a product bulletin from LP that references this protocol as acceptable. The warranty issue has been discussed at length on this site, and I think that warranty on this product is just not something that will ever be an issue. You could use a higher quality plywood cut into strips, but the nature of a rainscreen is such that I think pine is perfectly resilient, and the pullout resistance in the real world is such that 2x4 is overkill.
Thanks for the reply. I have a Hitachi nailer that works with 2-3/8 galvanized ring shank nails and the head is probably 3/8" diameters and .131 shank. I will be using 1-1/2 polyiso foam with 1 x 3 furring strips screwed into the studs. Do you remember which bulletin you referenced is available? Thanks.
Salesi, I can't find the technical bulletin I thought I remembered. Reading LP's installation instructions, it sure is quite specific on installations over continuous exterior foam. Requires 1.5" furring. Another bulletin references installation on masonry walls, specifying nominal 1x4's with a specific gravity (i.e. yellow pine, probably) and then doubling the nailing schedule to two nails per strip.
Nope, I guess installation is not allowed over 1x3's over foam, but I'm still confident enough to warrant my work on the project, and would do the same again.
Andy,
Ring shank nails through into 3/4" stock are next to impossible to get out. I can't understand why some siding manufacturers are being so conservative about their attachment requirements, and some others with similar products aren't.