Window Options and Noise Control

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RocketMan
Posts: 2
Joined: Mon Jan 30, 2006 5:23 pm
Location: In the Mississippi River

Window Options and Noise Control

#1 Post by RocketMan » Mon Jan 30, 2006 7:48 pm

We have just gotten an estimate to have our windows replaced in our home, which is about 30 years old and currently has single pane windows
that are draft.

We are looking at aluminum frame, double pane windows, for our 1 ½ story stone house.

As part of our update, we are also interested in trying to help address
some noise issues that we currently have from two adjoining neighbors
behind our property.

The first noise issue relates to the occasional pool parties one
neighbor has, with yelling, loud talking, and boisterous activity. If I had to quantify this noise it would be mid-to-high range. (If you have ever had this experience, think of the noise at a hotel pool). This pool is about 80 feet or so from the back wall of our home, on the other side of a wood fence.

The second noise issue relates to another neighbors new dog, which
barks constantly and has just been fitted with a "bark collar" to try to get him to quit barking (if the dog barks, he is shocked). This is a very large dog with a deep, booming bark, somewhat like the bass on a
passing car. This dog is about 100 feet from the back corner of our home, on the other side of a wood fence.

I have done a great deal of research on the noise issue, and read many
postings by Oberon and others at this site and others related to noise
control, sound measurement, sound properties, human sound perception
and the mechanics underlying noise transmission through windows.

Thus, I was pretty well prepared when the window company employee came out to measure and provide a quote.

I told him that I was strongly considering using laminated glass for
its noise control properties in all of the rear windows in the house.

However, the salesman suggested using a different set up, which I have
also seen discussed here and elsewhere.

The salesman suggested using 2 different sizes of glass in the dual
pane window. One pane would be 3/16" inch thick while the other pane would be 1/8" thick

I understand that this is done because of harmonics and the different
thicknesses of glass block or dampen different frequencies of sound.

The salesman quoted the price difference as about $100 per window for
using laminated glass, so the total for using laminated glass in all of
the rear windows would be about an extra $1,000.

The salesman claimed that his proposal would work just as well as
laminated glass and save us money.

I am looking for some guidance as to:

A. Whether the salesman’s representations are correct; and

B. If not, is the difference in the two methods as to sound dampening worth spending an additional $1,000.

Thanks.

earwax
Posts: 305
Joined: Mon Nov 15, 2004 4:52 am
Location: West Coast

#2 Post by earwax » Mon Jan 30, 2006 9:17 pm

I looked up a few window STC ratings and the different glass configurations. All of them show a heigher STC rating where they use Laminated glass as the thicker glass and a second piece of thinner glass. You can use tow pieces of annealed, but the ratings are not as good.

The lami will rase the ratings about 6-10 percent over the difference annealed glass thicknesses on the window brands I looked at. Hope this helps.

windowguru
Posts: 46
Joined: Mon Sep 12, 2005 3:28 pm

#3 Post by windowguru » Mon Jan 30, 2006 9:48 pm

not to get off topic, but aluminum frames search around for the pitfalls of those? Is triple glass an option for you? I know they do a good job of reducing noise.

Oberon
Posts: 205
Joined: Thu Oct 07, 2004 10:25 am
Location: East of the Mississippi

noise

#4 Post by Oberon » Thu Feb 02, 2006 8:11 am

In a word (or several - for those that know me), no, the salesman is not correct that the IGU with different thickness lites will have the same noise performance as will laminated glass.

But, before you start spending loads of money, a few thoughts and suggestions...

First, installation, installation, installation is important when considering energy efficiency, it is even more crucial for sound control...it MUST be done right in order to minimize outside noise.

Second, although laminated glass is the top-of-the-line option, installation of a dual pane with different thickness lites should make a significant difference versus your current single pane windows.

Third, I am not specifically a fan of STC ratings (there are better systems in use, but STC is the "established" rating)...but, in your case STC comparisons between different options will be a good guide. STC is specifically designed for "human voice" frequency range, and that is a good part of your problem....

Fourth, see the first thought and then consider your walls and the amount of insulation that you have in them. You could install the worlds best rated sound-proof window and still hear noise thru the walls...not very cost effective.

Fifth, you mention considering laminated glass to the windows facing the sound, but if you don't tighten up other windows around the house it is entirely possible for sound to enter thru those as well...that doesn't mean that improving the windows facing the sound source won't help a lot...just keep in mind that sound is persistant and like a burglar it will keep looking for that easy way in.

Curiously, aluminum frames are actually the best material for sound attenuation...but the very worst for energy issues. Depending on your environment you will have to consider if the trade-off is worth it.

Finally, a fixed window will outperform an operator in sound performance. A "direct-set" fixed window will generally outperform a "sash-in-frame" fixed window. In general, a casement will outperform sliders or double hungs in sound perfomance.

And finally, again, please remember the first comment / suggestion...installation...

Good luck!

researcher
Posts: 129
Joined: Tue Nov 30, 2004 11:39 am

#5 Post by researcher » Thu Feb 02, 2006 9:45 am

>>And finally, again, please remember the first comment / suggestion...installation...<<

It quite amazing when i am in a car setting at a red light next to a noisy diesel truck how much sound difference there is if your window is closed completely or open just a fraction.

Delaware Mike
Posts: 764
Joined: Fri Nov 19, 2004 10:44 am
Location: South Jersey, Delaware, Philadelphia area

#6 Post by Delaware Mike » Thu Feb 02, 2006 4:30 pm

This is the perfect time to continue on with this thread. I have a customer that is very dissatisfied with the increased sound inside of his house after his window replacement.

The customer is good friend on mine and we wanted to put him into a better window, but he was being pretty stubborn with what he was willing to spend since he will likely be moving after a year or two. His situation was like that of many, original wood windows about 25 years old with aluminum triple-track storms. He had not opened his windows in over 8 years, I'm not kidding. They were painted and swelled shut. My installers could not even get them open before removing them. His storm windows were caulked on really good as well.

There was no air infilltrationat all. Operation of one's windows would be a must of most homeowners, but with my friend it didn't seem all that important to him. His real concern was just to fix the place up enough for the "girlfriend" move in and be comfortable, which is understandable. What I didn't take into consideration was the fact of how quit his how was. Living next to a busy road there is a considerable amount of traffic that goes by his house. At night time there a big rigs that pass by often slowing for a light and railroad tracks ahead.

To the point, installation (1 year ago) went great, tight fit, everything insulated. I'm not going to mention the window manufacturer, but when the pros here mention that they don't carry a certain brand anymore, trust them it's for a reason. After addressing bowed sashes, missaligned interlocks, and air leakage in the jambs above the balances, we still can't come up with acceptable solution for the noise. The current vinyl windows are double glazed with PPG's Solarban 60 w/ argon fill.

The customer contacted the manufacturer for a price on having triple glazed sashes made with low-E and kypton, plus stronger balances. I wasn't quite shure if this alone would help all that much so I told him to make sure the two double hungs in his bedroom had laminated glass. The price was out of the question. I'll pay the most of the cost to put him into Schuco before I let him spend this kind of money. After reading what Oberon said, I'm real curious what he would do if this were his friend?

I just got off the phone with Schuco and learned a few things that I'm sure all of the seasoned pros already know. Laminated glass will be double-glazed only with Schuco because of the limited amount of space, makes sense. They cant't do any type of Low-E or gas filling, although they can do all types of tints to help with the sun. Right now I'm sure if they can even do a laminate upgrade with out the entire window being changed over to their heavy-duty FORCE V hurricane model due to the weight issues. My customer also needs an internal grid to match all of the other town house units.

My customer's first idea is starting to sound pretty good, "just pack out that brickmold/frame thing, cap it again and put some new strom windows on." I laughed at this at first.

Dave, FenEx, anyone.......

Mike
JMJ Windows

RocketMan
Posts: 2
Joined: Mon Jan 30, 2006 5:23 pm
Location: In the Mississippi River

Window Options and Noise Control

#7 Post by RocketMan » Thu Feb 02, 2006 10:36 pm

Thanks for the comments. The Internet truly is a wonderful thing.

In response to some of the comments:

1. What do you look for to make sure that you are getting a good installation, is it more than just making sure that the window units are sealed and caulked properly?

2. I am still struggling with the laminated versus non-laminated issue, I guess because it's so hard to predict and subjectively quantify noise reduction. I am still leaning to do all of the back windows with laminate or at least the two bedrooms where the noise is more of an issue.

3. I planned on the front windows being standard double pane windows since we do not currently have any noise issues with the front of the house. It's my unerstanding that noise travels in a straight line

4. I have never looked into triple panes, but will do so now.

5. The car window example is a good illustation of the importance off good windows, of course, that's a laminated window you are rolling up and down.

6. Let's suppose the windows are installed and we still have some noise issues. How do you tell whether the noise is leaking thru the wall or a window?

7. Our house is rock, so I would expect very little noise transmission through the walls.

Oberon
Posts: 205
Joined: Thu Oct 07, 2004 10:25 am
Location: East of the Mississippi

sound

#8 Post by Oberon » Fri Feb 03, 2006 8:50 am

Size matters - well, width and thickness anyway.

The wider the airspace between two lites of glass in a window system, the better the sound performance. A narrow airspace between two lites can actually enhance the sound - almost something of a megaphone effect.

The complaint that new windows can be actually "less quiet" than the old windows that they replaced can be quite valid. Mike gave a perfect example of why this can be true.
First, this was not a "single pane" window system. As modified it was a dual pane - although the panes were not mechanically linked.
Obviously, from the description, this "dual pane" was tight...there was no air (or sound) leakage around this set up. Also, the airspace between the original interior windows and the storms was probably a couple of inches wide, as well - ideal for attenuating unwanted sounds.
If someone wanted to design a "sound resistant" window system, then this particular construction, as described, would have made an ideal example...but, also as Mike said, it sure as heck wasn't a practical or comfortable living arrangement.

If a person has single or dual pane windows and needs additional sound protection, adding storm windows can help a great deal. But, with the caveat that the storms and the original windows have to be tight.

Loose windows pass sound.

If the orginal windows can be tightened and the storms are installed correctly (there's that "I" word again), then the air space that is created between the storm and the original window can help to prevent unwanted sounds from entering the home.

I only have a few minutes this morning, and while I will continue later (because I think this is fun!)...but, just to confuse matters further I am going to drop a few numbers and let everyone reading this ponder how potentially complicated noise reduction really can be...

I have discussed sound transmission loss in other posts...and without going into dB (at the moment) and how to use it, well, imagine a given dB (loudness level) and how different arrangements of glass affect this given loudness at different frequencies....

hope this makes sense...

1/8" glass, 1/4" airspace. 1/8" glass has a loss of 26dB at 100hz. But at 400hz, the loss is only 19dB. But at 2500hz, the loss is 46dB.

(Loss is a good thing - it describes how much quieter it will be)

1/4" x 1/2" air space x 1/4" has a loss of 29dB at 100hz, 31dB at 400hz, but only 36dB at 2500hz...so, this make up appears better at lower frquencies but not at higher when compared with the thinner glass and narrower airspace?

Well, at 5000hz, the 1/8" with narrower space has a 45dB loss while the 1/4" with wider airspace has a 58dB loss...confusing yet?

And finally, the 1/8" version has an STC of 28, while the 1/4" has an STC of 35.

-----------------------------------------

It gets better, just imagine when we increase airspace and add laminate! More later...have a great day!

steidle1
Posts: 16
Joined: Mon Feb 06, 2006 5:42 pm
Location: Richmond, VA

Re: sound

#9 Post by steidle1 » Tue Feb 07, 2006 4:52 pm

What does this all mean???

[quote="Oberon"]1/8" glass, 1/4" airspace. 1/8" glass has a loss of 26dB at 100hz. But at 400hz, the loss is only 19dB. But at 2500hz, the loss is 46dB.

(Loss is a good thing - it describes how much quieter it will be)

1/4" x 1/2" air space x 1/4" has a loss of 29dB at 100hz, 31dB at 400hz, but only 36dB at 2500hz...so, this make up appears better at lower frquencies but not at higher when compared with the thinner glass and narrower airspace?

Well, at 5000hz, the 1/8" with narrower space has a 45dB loss while the 1/4" with wider airspace has a 58dB loss...confusing yet?

And finally, the 1/8" version has an STC of 28, while the 1/4" has an STC of 35.

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