Humming Noise On Verandah Railings

by Keith
(S.A.)

We have a really loud humming noise coming from our metal veranda posts and rails when the wind blows. It keeps us awake. The system seems to be well put together but the noise is horrible! Even the neighbours hear it.

Built by Stirling Homes in South Australia.

Any ideas as to what may be the cause and how to fix it?

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Editor's Comments

This is an interesting situation. The first area of investigation I would look at is the possibility that the wind is moving at such a velocity against the metal railings that the two begin to resonate synchronously. It's just my first thought but could be totally wrong.

You do not say that the railing is rattling like you would expect to hear if the railing components were loose and banging against each other.

It almost sounds as if the railing is so well fitted together that it therefore has a unique and discreet resonance value. When the wind starts to vibrate it, there is no sound until the vibration frequency hits the internal frequency of the metal railing.

What you have described sounds almost how a musical instrument performs. If all the parts of a guitar are loose you never get any vibration or music from it. But if you set a properly tuned string into motion you can usually feel the entire body of the guitar resonate or vibrate in unison.

Maybe you have discovered a brand new way to make music, albeit in a rather annoying environment.