Oberon
10-31-2004, 07:47 AM
Okay, here is the second post. If this beginning makes no sense, then please read my post on dual pane versus triple pane windows...
Hopefully, it will make a bit of sense after that.
The original post in this thread was asking about controlling road noise...
Hope you enjoy my 2-cents...hopefully, it will start a bit of a discussion.
A few comments on STC and soundproofing.
First, STC is an average of an objects ability to attenuate sound across the entire sound frequency spectrum. STC does not provide specific frequency-deadening information which is really what is needed if you want to block a specific type of unwanted noise; in this case traffic.
As human's, we are born with the ability to hear from approximately 20 to 20,000 hertz. Hertz, or Hz, is how sound frequency is measured; like electricity is measured in volts, for example.
By the time we are teenagers, we have generally lost the ability to hear above about 13,000hz, or thereabouts.
Traffic noise is generally low frequency sound. Unfortunately, low frequencies are much harder to attenuate (opposite of amplify) or block than are higher frequencies...consider how often you hear the base sounds from the neighborhood kid's car stereo and not the higher pitch tunes when he is coming down the street.
When considering windows, there are generally three options available for sound attenuation.
First is laminated glass.
Second is a wider airspace between the lites.
Third is different thickness lites within the IGU.
Fourth would be a combination of all three.
Airport windows will generally have laminated glass on both sides of the IGU (Insulating Glass Unit) in an aluminum frame and with a maximum airspace between the lites. In an airport the primary concern is sound attenuation and energy efficiency is secondary. I mention this because the width of the airspace and the choice of window framing material affects both sound and energy efficiency.
Some folks will suggest triple pane glass for its sound deadening ability. And while triple pane is a slight improvement over standard double pane at lower frequencies due to the additional density of the extra lite, overall there is no difference in STC rating between triple and double pane provided that the overall airspace between the panes is constant between the two constructions. In other words, consider a triple pane with two 1/4" airspaces and a dual pane with a single 1/2" airspace...both using 1/8" glass...the STC will be identical if the IGU's are the same dimensions.
Using one thicker (3/16") and one thinner (1/16") lite in an IG construction will also help deaden sound because each lite is "transparent" to a different frequency and each lite will then attenuate the frequency that the other lite "passed".
I am going to stop now, and ask if anyone has actually read this far?
If so, and if you would like me to continue I would be more than happy to do so.
Believe me, this can get MUCH more complicated. But also, I think, that it will start to make some sense as it goes along.
Looking forward to visiting this site in the future!
Have a good one, and hope this helps a little.
And, as always the quality of the construction and especially the installation cannot be overstated!
Hopefully, it will make a bit of sense after that.
The original post in this thread was asking about controlling road noise...
Hope you enjoy my 2-cents...hopefully, it will start a bit of a discussion.
A few comments on STC and soundproofing.
First, STC is an average of an objects ability to attenuate sound across the entire sound frequency spectrum. STC does not provide specific frequency-deadening information which is really what is needed if you want to block a specific type of unwanted noise; in this case traffic.
As human's, we are born with the ability to hear from approximately 20 to 20,000 hertz. Hertz, or Hz, is how sound frequency is measured; like electricity is measured in volts, for example.
By the time we are teenagers, we have generally lost the ability to hear above about 13,000hz, or thereabouts.
Traffic noise is generally low frequency sound. Unfortunately, low frequencies are much harder to attenuate (opposite of amplify) or block than are higher frequencies...consider how often you hear the base sounds from the neighborhood kid's car stereo and not the higher pitch tunes when he is coming down the street.
When considering windows, there are generally three options available for sound attenuation.
First is laminated glass.
Second is a wider airspace between the lites.
Third is different thickness lites within the IGU.
Fourth would be a combination of all three.
Airport windows will generally have laminated glass on both sides of the IGU (Insulating Glass Unit) in an aluminum frame and with a maximum airspace between the lites. In an airport the primary concern is sound attenuation and energy efficiency is secondary. I mention this because the width of the airspace and the choice of window framing material affects both sound and energy efficiency.
Some folks will suggest triple pane glass for its sound deadening ability. And while triple pane is a slight improvement over standard double pane at lower frequencies due to the additional density of the extra lite, overall there is no difference in STC rating between triple and double pane provided that the overall airspace between the panes is constant between the two constructions. In other words, consider a triple pane with two 1/4" airspaces and a dual pane with a single 1/2" airspace...both using 1/8" glass...the STC will be identical if the IGU's are the same dimensions.
Using one thicker (3/16") and one thinner (1/16") lite in an IG construction will also help deaden sound because each lite is "transparent" to a different frequency and each lite will then attenuate the frequency that the other lite "passed".
I am going to stop now, and ask if anyone has actually read this far?
If so, and if you would like me to continue I would be more than happy to do so.
Believe me, this can get MUCH more complicated. But also, I think, that it will start to make some sense as it goes along.
Looking forward to visiting this site in the future!
Have a good one, and hope this helps a little.
And, as always the quality of the construction and especially the installation cannot be overstated!