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I've noted lots of wind noise from our standing seam panels, a roaring in the metal 'pans' forming the long panels that is, at times, deafening. My question: is there a reasonably effective solution?

Clips hold the panels 3/8" proud of the deck, for thermal reasons, but this gaps allows the 'pans' to chatter against the deck as shown in these short video clips taken 28 March 2022 during a wind and rain storm. If you watch the panels closely in these clips you can see them deflect with a 'pop' as the wind crests. I shot close to the panel axis to accentuate visibility of the panel cupping, which the rain also helps with.

Specifically, how can we shim the standing seam pans from below when the roof is installed? Below I show a commercial solution that stabilizes the panel pans with a network of purlins mounted above the metal panels, but it's a complex and rather expensive proposition.

Purlins mounted above are at least possible to access, since before I started hearing the wind 'roar', I counter-flashed the whole roof perimeter in metal and a weather barrier. That is, the area under the metal panels is sealed for waterproofing, as seen in these side and end views:

Side view of sealed roof system

End view of sealed roof system

I'm looking for ideas that won't require that level of intrusion, or require penetrations in the metal panels to insert shims as the latter would defeat the whole point of a waterproof metal roof.

The roof is composed of the following layers: ply, roofing paper, insulation, ply, thermal barrier, standing seam metal, as shown in the photo below:

enter image description here

Below I show notes from others sharing this problem, and one solution which is expensive, hard to install and (to me) ugly. Has anyone solved a similar problem?

Others with new roofing have heard similar noises:

We have a very nice standing seam metal roof that was installed about 1 year ago. It is properly installed, flashed, vented and we know of no problems with it. However, when the wind blows about 20 mph, as it is doing now, we can hear the roof rumble. There is no banging sound like a panel is loose, but an audible rumble.

To this one person responded:

Pretty normal. As the roof ages, some of that will diminish as the panels settle in a bit. More common when installed over purlins/battens.

There are somewhat related wind noises on other metal roof types, and many other similar threads:

We have a 20 year old standing seam roof. When we get wind from the north we hear a very loud rumble. From the outside you can even see the panels moving some. So loud it sounds like roof going to fly off.

So far as I've seen, the only commercial solution on offer are Windbar external purlins that partially prevent panel uplift. They do not eliminate noise completely and they are both expensive and -- at least to me -- are ugly as sin:

Windbar installation

Industry journals have noted this is a problem, e.g.:

When the standing seam clips are attached directly to framing, sometimes strong, gusting winds can build up enough pressure on the roof panels to cause noise. The wind can create a negative pressure and it can bow a standing seam roof panel up in the middle, because unlike an R-panel or some other through-fastened panel, they’re not fastened directly to the purlins or the joists. That wind gusting can bow that panel up real quick, and then it’ll let it go, and it can literally cause the panel to pop the top of that purlin or bar joist and make some pretty loud noises. And a lot of times you can hear that over in the conditioned part of the building. In addition to the noise the panels can cause in such cases, if they’re not secured, Buchinger says wind gusts can damage panels. “I have actually seen panels fracture over time from hitting those purlins over and over,” he says. “And so what I always tell erectors is glue a thermal spacer down to the top of the purlin or joist if you’re not going to put insulation down, just to deaden the noise, and also help prevent the panels from fracturing from bouncing over the years.”

Kevin Cain
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2 Answers2

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Your other question makes it seem like the bottom and top of the panel are open for the 3/8" air gap, how are the top and bottom of the panel closed?

16" wide 24 ga metal panels with no ribs or striations for reinforcement is crazy. I did 21" 22ga metal panels for vertical siding. I have some panels that are 22' tall but I did end up with some slight oil canning in a few of the panels. I opted for no striations as well but I get zero deflection/noise, then again a roof is likely subject to more wind loading. I have 1/2" air gap under my panels.

Since it is 50' I'd probably try for a pieces of metal maybe something like this T shaped metal except 3/8" tall. You could get a fabrication shop to make something for you. Push it in 10' lengths and put it in the middle of the 16" so that you are reducing the unsupported width of the panel. Possibly cut a horizontal slit in the up stand and add a little connector to receive the next piece and keep them inline.

wall bracing metal shape example

Fresh Codemonger
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Your metal roofs job is to protect the roof layers underneath it from the elements (principally: rain, sun, and wind). Letting wind under the metal is also letting the wind drive rain under it, which will prematurely degrade your metal roofing and the underlayment.

The correct fix is to enclose the top, bottom, and sides of the roof with appropriate trim, so wind can't funnel in there. Yes, the matching trim is expensive, but so too is failing to install it. An improper installation (one that doesn't match the manufacturers instructions) voids the warranty.

It appears both ends of the panels are still open. A potential improvement could be using a fish tape / wire puller to retroactively pull in backer rod (eg: 5/8" backer rod) under each panel. I adapted this idea from the Metal Construction Association's Metal Roof Installation Manual, who include backer rod in their arsenal of options to mitigate oil canning.

Matt Simerson
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