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How to lap plywood on exterior siding, without a drip cap?

Rocky12 | Posted in General Questions on

Hi guys, I have a shed style roof, similar to the photo attached.

At he very top corner of my wall, the breckenridge plywood siding didn’t make it up to the top. It’s about 2-3″ from the top wall trim.

I cut a traingle piece to fill the space but I really want to avoid using a drip cap because it would look aweful….And I don’t have a 3/8″ (thickness of plywood) similar color drip to use.

Given that this is at the very top of the wall, would I be ok installing the plywood without a drip cap, and just caulking the seam?

Are there any other solutions?

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  1. GBA Editor
    Martin Holladay | | #1

    I'm not familiar with the term "Breckenridge" siding, but I assume that it is similar to what I call T-111.

    What do you mean by "drip cap"? Do you mean some type of aluminum Z-flashing? Or is this some type of wooden trim?

  2. Rocky12 | | #2

    Hi Martin it is cedar plywood. Yes I am talking about z flashing in between the two pieces . Is there a way for me to avoid this ? As I mentioned it's literally at the top of the wall 2" below the top wall trim

  3. GBA Editor
    Martin Holladay | | #3

    You can probably skip the Z-flashing -- especially if you have generous roof overhangs like those shown in the photo. If the wall is exposed, and there are no roof overhangs, water might eventually get into the joint and cause swelling.

  4. Rocky12 | | #4

    Thanks Martin. Actually my overhang is only about 4 inches past the siding. Do you see something like that fail often ? If I keep it caulked and painted yearly think I would be ok? I do also have rainscreen behind

  5. GBA Editor
    Martin Holladay | | #5

    Assuming that the 4-inch-wide roof overhang isn't too far above the horizontal seam we're talking about, you should be fine. And you don't need to get out an extension ladder to caulk the seam every year. (Even if you think you're going to do that, you won't.)

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