Vinyl siding movement?

Did an inspection on a townhouse. Had to use the drone to view the roof and some sections of siding. On one side I noticed what looks like movement in the siding, but I’m not sure. It’s vinyl siding, townhouse was built in 2009. I think it may be movement as one end of the siding appears to have come out from under the neighboring piece and appears to be less faded. I also noticed how there’s a gap on a couple of pieces at the joint. I figure I’d ask and see if anyone else has seen anything like this. If so, what am I looking at? Thanks a bunch,

Vinyl siding is suppose to “move”, that’s why it’s nailed loosely, to allow for expansion and contraction due to temperature change, especially along the longitudinal direction.

Improper installation is the primary reason it buckles, bulges, warps, bends, etc.


Thats a lot of movement , more than a inch wide slot in the nail flange will allow for. . Probably heat coming off that roof along with improper install, likely over driven fasteners.

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Yup, that is right, what Dominic wrote.

I can understand the heat affect coming off the lower roof causing some of the buckling and expansion, but what don’t make sense is the longitudinal shrinkage at the joints to show that faded area. To shrink that much would make it come out of the J-channels.
The expansion vertically would give you that buckling at the seams though, like we see.

Hey guys, Thanks for the input! I’ve nailed some vinyl siding before when helping out on a Habitat house so I’m aware there will be some movement allowed. This one had me puzzled though. I appreciate the input regarding the heat from the neighboring roof. I hadn’t considered that (even though I’m down here in Alabama’s 98 degree October weather). It seems to make sense though seeing as how the majority of the effect is down closer to the neighboring roof. I couldn’t see any signs of water penetration on the inside due to a fire barrier on that portion of the attic wall.

In my report I’ll note that the siding is seeing the effects of heat from the neighboring roof that has resulted in some buckling and expansion and advise for future monitoring.

Drones becoming more and more powerful…