Wavy fiber cement siding
tjones1014
| Posted in General Questions on
We just had Hardie put up over the top of Benjamin Obdyke’s Slicker MAX (on OSB sheathing), and the walls where there are longer runs look wavy. Pic attached, though it doesn’t quite do it justice.
My siding guy says this is normal. He said, “Typically when the longer boards are installed, you’ll see that. The fiber cement material is meant to be a little flexible so that way it lasts longer and breathes.” Google tells me a different story.
I can only see it when I look at the wall at a certain angle. Is this normal/acceptable? Can this cause more issues down the road?
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Replies
tjones,
There are two types of wavy cement-base siding. The first is when the board has gaps between it and the one underneath due to inadequate fasteners. The second is when the top of the board is wavy due to an uneven substrate, or uneven compression at the fasteners. That second one is what it looks like to me in your photo. The whole flexible/breaths argument is nonsense.
I'm wondering if it's because of the rain screen underneath or an unevenly built wall. Is this something that needs to be redone, or is this just an aesthetic issue?
tjones,
Always hard to diagnose from a distance, but I suspect their nailer compressed the mesh differently as they sent along the boards. As long as there are no gaps where the boards overlap it's just an aesthetic issue.
Wall is wavy and the hardie follows the wall. It’s common to see wavy hardie on long runs.
Yup. Same here. I have about a 45' run and even with trying, there is some wave in it. Best is not to look at it from that angle than it is not wavy.
Plant a shrub off the corner.
Give some consideration to the paint sheen when it gets painted, unless it will be a very light paint color. The more gloss, the more the waviness will tend to visually stand out, especially with darker colors. Low sheen or matte can go a long way to de-emphasize instead of highlighting it.
I was able to grab some better pictures today. There are some gaps between the boards in some places, none larger than 1/8" max. In your opinions, is this still just an aesthetic issue?