Plastic cap nails for WRB causing bumps in lap siding
BrunoF
| Posted in General Questions on
Is there a life hack out there for being able to use the plastic cap nails to secure the WRB while avoiding interference with fiber cement lap and panel siding?
my initial thought is to use staples and just not worry about them or tape over them but that seem like a horribly inefficient use of labor.
any ideas?
thx!
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Replies
BrunoF,
From my perspective cap nails are necessary a) When the WRB will be exposed for a long time and may blow off. b) For warranty reasons (for what that's worth...). I use staples.
Cement based siding, being a reservoir cladding and fairly air-tight, should be installed over a rain-screen strapping.
Malcom, thx! My setup does not call for a rain-screen, just Hydrogap drainable house wrap. There are no crews here in central NC that I have found who know how to detail a house with a rain-screen so I need to balance best practices with the practical side of installation.
You could use a fully adhered WRB.
Benjamin Obdyke hydro gap SA drainable house wrap? Though I personally have not used this product, it looks as though it wouldn’t need cap nails, and it appears to provide some of the benefits of a rainscreen.
Ben
Hydrogap SA is also outrageously priced. Bruno do you have any pictures of how much it’s affecting the siding? I’m putting the Hydrogap over foam so I make sure to sink the cap nail in. Hydrogap is super durable in your case I would just attach it using roofing nails, and it should hold up fine.
No pics yet as I am in the final planning stages before starting framing next week…just trying to avoid issues. And yes, the SA version is way too expensive to justify using.
What sheathing are you using under the Hydrogap? Are you detailing it as your wrb?
I am using plain OSB, taped and sealed as the sheathing and primary air barrier. The hydrogap will be the water barrier. This seems to be by far the most cost effective way to get good air sealing and bulk water protection.
For those saying that Hydrogap SA is "outrageously priced," it's about $1.37 per square foot--within two cents of Pro Clima Adhero or Siga Majvest SA, comparably high-quality products without the benefit of the Hydrogap nubbins that allow drainage.
Henry VP100 is probably the best-known and most-used self adhering WRB but it's not as tough as the other options, and costs $0.88/sf..
Plain Hydrogap is about $0.38/sf. Tyvek Drainwrap is about $1.13/sf. Typar's version is only $0.30/sf.
After the roof and site drainage, the WRB might be the most important component of the house when it comes to keeping water-related problems at bay. You probably have 1500-2500 sf of wall area, let's say 2000 sf. The cheapest drainable housewrap, Typar, would be about $600 plus fasteners and tape. (You ARE going to tape the seams, right??!) That's at least $700 for the house. Plain Hydrogap plus fasteners and tape would be around $900. Hydrogap SA would be about $2700, with faster installation, no fasteners or tapes needed. You'll get a reliably watertight and airtight house, the siding will drain and lay flat.
I'm pretty frugal but if I didn't have the labor force to do a proper rain screen, I'd happily pay an extra $1800 to get a premium result.
I may have a larger house than assumed as I need 5000 sqft of hydrogap at a cost of around $1900. Since it is not easy around here to get the crews to put a roller on zip tape, I can’t imagine getting them to roll the SA material on the entire house (unless it doesn’t have to be rolled). Unfortunately, due to costs and lack of familiarity with high performance build techniques, a lot of this project has to be grounded in “better than code & good enough”. Rather than “best and perfect”.
Also, I am under the impression from the Ben Obdyke website that they recommend against taping hydrogap so I had not planned on it.
Michael, these are all valid points for sure. Something to be said about having no fasteners in your wrb. If I used osb wall sheathing I would heavily consider a self adhered membrane as well.
Staples will get ripped off during any high wind episode during construction. I am surprised the plastic nail caps are telegraphing onto the siding. They are usually so thin and flat, it shouldn't pose a problem. They use them on roofs to hold down the roofing membrane. The plastic cap increases hold down area vs just a nail or staple.