Hardie Plank detail where roof-line meets sidewall

Old 11-15-16, 07:34 PM
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Hardie Plank detail where roof-line meets sidewall


Since this is a prime area for moisture damage, I want to make sure I'm doing what I can to protect the materials.

The first image shows where the roof-line meets the sidewall. You'll see I've installed a PVC "band" a couple of inches above the shingles. There is aluminum Z-trim above that. I've line-sketched (roughly) where the planks will be installed. I've also traced the edges of the kickout flashing with blue lines to make it easier to see.
My first question is; where the planks end over the Z-trim, should those edges be caulked (I've been using OSI Quad sealant)?
It's hard to see the text in my image, but, basically, I ask the same question as above "should I caulk?"
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The next image narrows in on the kickout flashing. An end of a plank will sit above the small area behind the kickout flashing and above the shingles (probably only about one square inch of shingle).
For that area, do I need to make sure that the Hardie plank is the recommended 2" above? (the text in the image, basically, asks the same question, i.e., do I need to be 2" above that tiny area?).

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Any other tips or suggestions based on what you see in the images would be greatly appreciated.

Thanks in advance.
Old 11-15-16, 08:36 PM
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If you want to follow the instructions to a "T", you would treat that like a drip cap above a window... 1/4" clearance, no caulk. Prime and paint cut edges prior to installing.

I would advise you to also clip the tips of the angles. Instead of being like a perfect triangle and coming to a sharp point, start trimming the siding angle - where it is no longer exposed - (6" from bottom edge on the 7 1/4" or 7" from the bottom on the 8 1/4") upward at a sharper angle so that the point is farther away from the z-flashing... that way water, ice, trash, etc are less likely to catch that point as it flows down the z-flashing and travel horizontally on top of /behind the siding.

I'd also recommend the top of your z-flashing either be taped or slit and tucked behind the wrb.

It looks like the kickout flashing needs to be pulled down the roof another inch or two, you shouldn't have ANY roof showing behind it. It should also be taller or it won't deflect the water that's coming down the z-flashing.

Below the kickout, your big flat piece of flashing can shed out over/on top of the siding below, which you have done. The next row that you would think might butt up to the left side of the kickout and get caulked should actually go BEHIND the kickout as far as possible. The next row of siding that goes over the top of the kickout gets a slot cut in it so it can drop down over both sides of the kickout, then that slot in the siding gets caulked to the kickout.

You could also trim the top corner of the kickout so it has a nice gentle radius on it. I would hate to see you poke your eye out on it when you are cleaning the gutters someday. LOL

PS: have you discovered Gecko Gauges yet?
Old 11-16-16, 12:02 PM
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Thanks for your feedback @XSleeper. I do appreciate it.

OK. For the ends of the planks that terminate on the Z-flash; I'll clip the tip of the triangle, paint the ends (as usual), and skip the caulk. That will look better too. I'll probably paint a couple inches of the backside of the plank near the end too.

The WRB is over the step flash, but not over the Z-flash. I can certainly tape the top edge of the Z-flash if you think that makes sense.

That kickout flashing is prefab. If I had moved it further down the roof-line, it would have overshot the gutter. I did struggle with deciding where to best position that kickout.

Good "point" about the edge of that kickout. Rounding the edge is smart.

I'm using "Solo Siders" (vs. Gecko). They work pretty well. The one negative comment I have about them is that, if you forget and finish nailing the plank tight to the wall, it's a real B--witch to get those suckers out.

Thanks again.

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