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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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  • What does the end of the panel look like? Do you know what your roof assembly looks like? Is there an air space between the metal panel and the roof sheathing? – Fresh Codemonger Dec 13 '22 at 01:53
  • What are the metal panels connected to? – RetiredATC Dec 13 '22 at 05:01
  • standing seam metal panels are typically fastened in the hidden rib and it would need to at least hit the sheathing if not the framing under the sheathing. they look like 16" oc seams so I'd guess they are hitting the framing. – Fresh Codemonger Dec 13 '22 at 05:47
  • @FreshCodemonger, you can see the metal panel terminations in my separate post here: https://diy.stackexchange.com/questions/262373/end-caps-for-standing-seam-metal-roof. There is in fact a 3/8" air gap under the panels that I have added to my question; clips hold the panels proud of the surface for thermal reasons, but allow the 'pans' to chatter against the deck. – Kevin Cain Dec 14 '22 at 02:11
  • @RetiredATC, I added photos above that show the roof constituents in cross-section – Kevin Cain Dec 14 '22 at 02:17
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    could you take a 3/8" thick piece of ply and put it into the middle of the panel - adding some support? or 3/8" piece of XPS insulation maybe 2" wide. What gauge are the metal panels? – Fresh Codemonger Dec 14 '22 at 02:53
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    I think the comment by @Fresh Codemonger makes the most sense. Something needs to supply some support from underneath. BTW, is this (a 3/8" gap) the way the manufacturer instructed that the panels be installed? If so, what do they say? – RetiredATC Dec 14 '22 at 04:07
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    My guess is that "Clips hold the panels 3/8" proud of the deck" is where your problem is. Because there is an air gap, the panels can rattle and pop. I'd think you'd need to wedge 3/8" foam (or similar) into these gaps to prevent it from banging around. Of course, you can't do a continuous piece because you've still got to allow for expansion. I've got to say, though, that if this seems to be a common problem, there ought to be a common solution and if you haven't found it in your extensive research, then... move. :( (mostly kidding) – FreeMan Dec 14 '22 at 17:05
  • @RetiredATC, the 3/8" gap is intended by the manufacturer, who says that they've never heard (literally, and figuratively) of this problem. The other brave souls who complained of similar sounds contradict the manufacturers' account, but the bigger problem is that there is no way to insert shims since the seams were locked during our installation with a mechanical seamer, as intended. Therefore, I've edited the question to reflect this discussion and frame the real question: how can we shim the standing seam pans from below when the roof is installed? – Kevin Cain Dec 15 '22 at 04:51
  • @FreshCodemonger, the roof metal is 24GA and the seam centers are 18". It would be possible to mount ply/metal spacers atop the panels as your suggest, a bit like the commercial purlins I noted but without the overarching supports. – Kevin Cain Dec 15 '22 at 04:59
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    I was actually wondering about inserting it below the metal panel into the 3/8" air gap. It just depends what your assembly looks like. Are the air gaps continuous 16" wide, 3/8" tall? – Fresh Codemonger Dec 15 '22 at 05:52
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    From the edge facing outward, could you push a 2-3" wide X 96" long piece of 3/8" Styrofoam insulation under the metal roofing and it stay in place with a friction fit? – RetiredATC Dec 15 '22 at 06:27
  • You've taken a couple of cores. Could you take those from multiple places, reach through the hole with a can of spray foam & give it a little shot (remember - in standard form, that stuff expands a lot!), then plug the hole from the bottom? It appears that the bottom layer is just plywood, so I'd expect some sort of finish layer (if it's the outdoor structure from your newer question) would hide the plug, or if it's an attic, who cares what it looks like. – FreeMan Dec 15 '22 at 13:57
  • Yes, @FreshCodemonger, the air gaps are continuous 16", 3/8" tall running 50'+ on either side of the roof valley. There's no access without cutting into the roof, which seems an awful idea since it would seriously compromise the waterproofing. – Kevin Cain Dec 16 '22 at 06:09

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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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    Seems like a good idea. I would imagine, though, that once this is shoved in place, the roofing would need to be screwed (or otherwise adhered) to the bracing to keep it from being lifted by the wind. I can see the wind lifting the panels if there's just the slightest amount of slop in their installation, then it banging down onto the metal Tee and simply making a different noise. Maybe a slow cure epoxy or construction adhesive could work - applied as its pushed in, then, hopefully leaving enough on the top of the Tee to still stick at the top. – FreeMan Dec 16 '22 at 13:30
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    Possible. I'd recommend trying one out first and seeing how it performs. It is possible if the standoff is tight to the metal that the panel will be in the maximum deflected state and the wind won't be able to deform it. Kind of a brutal problem given the panels are 50' long. – Fresh Codemonger Dec 16 '22 at 16:26
  • @FreshCodemonger, I like your idea. As you might imagine, I flashed (and counter-flashed) the perimeter with metal and a weather barrier, for waterproofing. I've added a photo showing this; the result is there's no way to slide members into place. I suppose the only option is to penetrate the roof to insert stand-offs at regular intervals, but that seems like a terrible thing to do to a metal roof. – Kevin Cain Dec 17 '22 at 18:12
  • @FreeMan, your point is well taken: struts under the panels, especially mobile ones, may modify the sound I'm hearing, but not solve it. Purlins on top would potentially be reversible (though expensive and ugly), while inserting long members in a tight space could be a one-way trip. – Kevin Cain Dec 17 '22 at 18:21
  • @FreshCodemonger, Interestingly, the manufacturer maintains the 3/8" gap is normal, did not recommend shims during install and thinks they're not needed. For anyone considering a standing seam roof in a windy spot, I suggest you shim as you install. – Kevin Cain Dec 17 '22 at 18:24
  • In my experience, panels without striations not only not crazy, it is standard, but perhaps in your area of the country it is. Panels with ribs in a residence for example, look pretty bad, they give that corrugated look imo. However, I think you're in the right track with the solution, except I would instead add a piece with a wider, softer top like something round to avoid marking the panel but still creating that bowing effect. – sheetmetal85 Mar 02 '23 at 12:35