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Automotive Glass for House Windows

Blocks noise better
  [vote for,

If you ever heard a jet fly low over your house, you probably heard quite a bit of noise. But if you were in an automobile with the windows up, and a jet flew equally low over the car, you likely would notice rather less noise. Therefore the glass ordinarily used in the automobile is simply better than the glass ordinarily used in house windows, for blocking noise.

I think part of the secret is that automotive glass is "safety glass", two layers that are bonded together (the glue or whatever counts as a third layer) to drastically reduce the chance of shattering. Being a fairly hard substance, glass normally conducts sound easily --but that bonding layer, in automotive glass, is most certainly not a hard substance. Much noise simply gets absorbed/blocked by it.

So, the Idea here is that we should use safety glass for house windows --not so much for safety, though, as for noise reduction. We could even use thinner layers of glass than are used in cars, bonded together (making up one "pane" of the double-panes or triple panes used in thermally insulating windows). Because we want the sound-absorbing layer more than we want thick glass.

Vernon, Sep 04 2014

Saflex® http://www.saflex.c.../ArchiAcoustic.aspx
Saflex® interlayer provides superior noise reduction capabilities compared to ordinary glass [xaviergisz, Sep 04 2014]

FDS Glass http://www.fdsglass..._Architectural.html
Bisn ® PVB interlayer film provides good sound insulation [xaviergisz, Sep 04 2014]


       Double glazing?
not_morrison_rm, Sep 04 2014

       Double glazing works very well for noise. Even better is non- parallel double glazing. In a regular double glazed window, the two panes are separated by an inert gas, but this still allows one pane to compress the gas and pass on vibrations to the next one, like a drum. If you angle one pane relative to another, then a component of the energy is directed toward the wider end. Where you can put a sound absorbent material. They use this technique in recording studios.
bs0u0155, Sep 04 2014

       "Double glazing" is just another way of talking about the "double panes" already mentioned in the main text.
Vernon, Sep 04 2014

       On triple pane windows I've heard that if the gap between one pair of panes is different than the gap between the other two that the two gaps will block different frequency ranges so overall noise reduction will be better than a standard tipple pane window. I didn't see any data saying how much of an improvement this would make or how much different the spacing should be.
scad mientist, Sep 04 2014

       The only glass in a car that is laminated is the windshield. In that case it is two pieces of regular glass laminated with a piece of plastic. Some cars also have a plastic layer on the inside.   

       All the side and rear windows utilize tempered glass which is one single piece of glass. It is thicker than your typical window glass by about double. I suspect this difference in thickness has more to do with the dampening of noise than anything.
jhomrighaus, Sep 04 2014

       the BMW 5 series used to have double glazed side windows, ostensibly to reduce cabin noise. They dropped it in subsequent generations because the thermal insulation was too good, meaning it was a pain to de ice, and if it was cold enough outside, would re-ice as you drive.
bs0u0155, Sep 04 2014

       One of the reasons car glass is good at deadening sound is that it's usually held in a rubber gasket, rather than being fixed rigidly. This helps to absorb vibrations imparted to the glass by noise, and prevents them being transmitted to the metal bodywork.   

       Laminated glass is not especially good at blocking sound, because the laminating material has too high a modulus to absorb much of the energy.
MaxwellBuchanan, Sep 04 2014

       Is the problem measurable?   

       Car interiors are noisy and your tolerance for noise may increase while driving, effectively cutting out some jet noise. Or, jet noise may be acoustically occluded by the car noise. There may be perception issues here.
the porpoise, Sep 04 2014

       //There may be perception issues here.// Story of my life, mate.
MaxwellBuchanan, Sep 04 2014

       I think Vernon is right that cars are more quiet than houses when they are not moving and the engine is not running. The laminate glass idea is flawed because only the front windshield is laminated. The rest is tempered.   

       Maybe it's the tempered glass. Tempered glass is very hard, and is under some kind of internal tension; when it breaks, it all breaks at once. Maybe this bounces sound better?   

       I think, though, the fact that a car is practically hermetically sealed has more to do with it. Houses have all kinds of gaps and cracks and windows and doors that don't fit right. Holes let the sound in. Cars are designed not to have holes. That's why you can tell immediately if the window is rolled down a bit or if the door is ajar on a car.
nomocrow, Sep 06 2014

       //than houses when they are not moving   

       They move quite a lot here sometimes. Ok, I raise you one double-glazed window with jelly in between the panes.   

       Good damping qualities and you can eat it in hard times.
not_morrison_rm, Sep 06 2014

       Hand crank or little rocker switch to open and close window ?   

       / Automotive Glass for House Windows /
popbottle, Sep 07 2014


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