Help with sound transmission thru sliding door- info please

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bsedgwick
Posts: 13
Joined: Tue Feb 21, 2006 6:13 pm

Help with sound transmission thru sliding door- info please

#1 Post by bsedgwick »

I have posted twice with no response. I am having a terrible problem with outside noise coming in through a new Simonton profinish sliding door. This did not happen with my old sliding door which was an aluminum double paned door (brand not known). It was in the townhouse when we bought it in 2003. The only problem we were having was draftiness in the winter. I would gladly trade back, accept the draftiness and lose the noise but it has been discarded. My questions are threefold:

1. What makes for good sound insulation in a door?
2. Which manufacturers do the best with sound problems?
3. What would make a new door w/ low e, argon gas reverberate? It almost sounds like the door is too rigid, like it attracts vibration.

Any help on this is much appreciated.


Bill
Last edited by bsedgwick on Tue Jun 27, 2006 8:59 pm, edited 1 time in total.

Guy
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#2 Post by Guy »

Your windows are rated for "Sound Transmission Class" (STC) & "Outdoor-Indoor Transmission Class" (OITC). The rule of thumb on sound is, the thicker the glass spacer, the better the sound blockage. Meaning the more room that is given between glass sheets lets the sound wave bend more. Ounce the sound hits the first sheet of glass and enters the inside space. It will bend in another direction before penetrating the inside sheet. With a thicker distance between sheets of glass the sound wave weakens more before getting through the next sheet.

More than likely your old doors had thicker glass or an extra storm unit on the outside. We see a lot of the older aluminum doors with two more doors installed as a storm unit. So you really have four doors where you now have two. If you had the storm unit then you had double protection from sound. Your new door must have thinner glass than the old one. You can see if they can upgrade your glass to triple glazed, which adds a laminate sheet between the two glass pieces. You could also go with laminate glass in your doors. This is the same glass used in your vehicles windshield. They may also call it "Sound Glass" that is used in areas with potentially loud noises. In any case it will cost more to change out the glass. It will be up to you to negotiate the pricing with them. Good Luck!!!

bsedgwick
Posts: 13
Joined: Tue Feb 21, 2006 6:13 pm

Sound transmission through sliding glass doors

#3 Post by bsedgwick »

Thank you so much, Guy. I have been at such a loss about this. Could you direct me to a website or book where I can read more about STC and OITC designations? Are all residential doors rated STC or did you just know this from the brand and model information I furnished?

The door which I replaced did not have a storm door, but it sure did block the sound. I don't know the age of it, but it apparently was a really good door. Too bad I didn't keep it.

Are you saying that the manufacturer should be able to just replace the glass instead of the whole door? Will the frame on a Simonton Profinish door accommodate the kind of glass your are talking about?

Your information has made my day. Thanks again,

Bill

InfoSponge
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Joined: Tue Jan 17, 2006 2:25 am

#4 Post by InfoSponge »

You should be able to replace the glass with some other options (maybe not all that the company offers) without replacing the whole door. There are several options to reduce sound transmission including laminated glass (probably your best bet), wider airspace between the glass, triple pane, different glass pane thicknesses in the same IGU, thicker glass, heat mirror films, storm doors, ensuring the installation is tight/insulated, better door STC/OITC ratings, etc.

Most companies have STC numbers available for their products, but they may not be easy to come by. Check their web site and check with your local dealer to see if they have a detailed product catalog written for architects/builders. You can also call the manufacturer themselves.

STC Help: http://en.wikipedia.org/wiki/Sound_transmission_class
OITC/STC Help: http://www.jeld-wenresearch.com/_pdfs/S ... stment.pdf

bsedgwick
Posts: 13
Joined: Tue Feb 21, 2006 6:13 pm

SOUND TRANSMISSION THROUGH GLASS

#5 Post by bsedgwick »

THanks, Info Sponge. That is very helpful. But could you tell me what a heat mirror film is and where I might get information on that? I really appreciate your help.

Bill

InfoSponge
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Joined: Tue Jan 17, 2006 2:25 am

#6 Post by InfoSponge »

The heat mirror I'm referring to is a thin clear plastic sheet between the glass panes, so it isn't something you can slap on an existing door. I don't believe that Simonton offers any heat mirror glass products, so it probably isn't an option if you get your replacement glass from Simonton.

Many people don't like heat mirrors between the panes of glass because they have the reputation of discoloring/warping over time, while others say the more recent heat mirrors are much more reliable and they offer better performance for both sound and heat transmission.

bsedgwick
Posts: 13
Joined: Tue Feb 21, 2006 6:13 pm

Sliding door sound transmission problems

#7 Post by bsedgwick »

Guy and Info Sponge: your responses have been so helpful. Do either of you or anyone know how you test a door to see if it is meeting the minimum standards set up for sound tranmission? Who would do a test like this and what would be involved? Thanks,

Bill

InfoSponge
Posts: 155
Joined: Tue Jan 17, 2006 2:25 am

#8 Post by InfoSponge »

I doubt most window installers have the equipment/experience to do actual dB reduction testing. You could probably hire a local engineering/testing firm to bring in a SPL meter and test dB reduction of your whole house envelope, but I don't expect that would be cheap. If you are a technical person you could purchase such a meter yourself (search on google/froogle for "SPL meter") and do a rough test, but you'd need to produce the right frequency sounds that STC measures (human voice, I believe) in a repeatable manner, know the equations to convert the difference inside/out to a STC number, your state's minimum building codes, be sure your SPL meter is accurate somehow, etc. Your number would just be a very rough estimate, since it isn't a lab test, and it wouldn't just measure the doors, but it might be fun to try. Assuming the install is not the problem, you're probably better off just replacing the glass or getting a whole new door, I'd guess, but you could look into these other options if one sounds workable/affordable.

(edited to state you can estimate dB reduction of the house, but not the actual STC rating or your door, since Guy and Oberon are correct there)
Last edited by InfoSponge on Sun Jul 02, 2006 11:13 am, edited 2 times in total.

Guy
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#9 Post by Guy »

You couldn't do any testing of the door glass outside of the laboratory. The surrounding sounds would pollute the correct readings. The money you would spend in trying to accomplish your rating could buy you a new door. It would be cheaper to look into new glass or door panels.

bsedgwick
Posts: 13
Joined: Tue Feb 21, 2006 6:13 pm

SOUND TRANSMISSION THROUGH GLASS

#10 Post by bsedgwick »

So, if I hear a sound coming through glass which I say is too much and a door company does not acknowledge that there is a problem. Is there a way to say how much sound is too much? Any other reasonable way to measure?

Bill

InfoSponge
Posts: 155
Joined: Tue Jan 17, 2006 2:25 am

#11 Post by InfoSponge »

I don't expect you'll find an accurate and inexpensive way to measure STC of the installed door. As we both said, your best bet is probably to replace the glass or the door. A good dealer will help you through the glass replacement process, and do it for a reasonable fee, since you are unhappy. If they refuse to help you in any way, go to another Simonton dealer and get a quote to replace the glass. My guess is that your only legal recourse (unless they stated in writing that the door will be quieter) is that the door's official STC rating is below your area's minimum building codes, which is very unlikely to be the case. You could also call Simonton and express your concerns, and maybe they will have some other suggestions.

Oberon
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noise

#12 Post by Oberon »

You won't find a way to do STC field measurements because STC is entirely a lab test and is based on precise conditions that are not applicable once the window (or door, or wall) leaves the lab setting.

Unacceptable noise levels can be EXTREMELY difficult to quantify in many situations. What bothers you might not even be noticed by someone else. Even using a sound meter to measure a specific SPL (sound pressure level) may not provide an acceptable answer.

If you have read any of my previous posts about sound, you might have noticed that I am not a huge fan of STC - I much prefer the OITC that Guy mentioned in his reply.

BUt, a bit of explanation of STC follows so if you feel the need to read here goes...

STC stands for Sound Transmission Class. It is a laboratory rating based on some very specific criteria. Using STC to compare the sound-blocking capability of different window styles or brands is certainly not a bad idea. Generally speaking, a window with an STC of 35 is going to outperform a window with an STC of 31. But, STC is sort of like mileage ratings on a new car…not always as accurate as one might hope.

In order to determine the STC of a window in a specific circumstance or location, it is first necessary to determine the amount of Noise Reduction (NR) required for that particular situation. STC is a rating that is independent of the conditions under which the window or door will be used - I say again - STC IS A RATING THAT IS INDEPENDENT OF THE CONDITIONS UNDER WHICH THE WINDOW OR DOOR WILL BE USED.

These conditions might include background noise, window area, even sensitivity to noise of the occupants. Noise reduction requirements are affected by these conditions so that windows with the same STC might have very different NR requirements when used in different situations.

There are really three primary issues involved in determining "noise" – frequency, level, and duration. Sound frequency and sound level are combined into what is called a "dBA" or A-filtered value in order to quantify the sound in relation to the human perception or ability to hear it.

Duration is added because even a relatively quiet sound can be come annoying when it persists for a certain time. Using figures derived from these three descriptors, a sound professional can determine what is required to attenuate (opposite of amplify) the inappropriate sounds.

Because it is generally quieter at night, report agencies who have to deal with people and noise actually assign a 10dB penalty to noises at night (generally between 10:pm and 6:am). What this means is that since there is less background noise it is easier to hear sounds with a lower pressure level (loudness) at night than in the day.

Consider cutting your grass while listening to music thru headphones. As long as the mower is running, you can comfortably keep the music thru the headphones quite loud – yet when you turn off the mower, suddenly the music seems uncomfortably loud. This is part of why STC values can be difficult to quantify – background noise plays a big part in what you can actually hear…and you may be so attuned to this background noise that you quite literally filter it out.

Sound frequency is measured in Hertz, or Hz. We are born with the ability to hear from 20 to 20,000hz, although we may have lost the ability to hear much beyond 13 or 14,000hz by the time we are adults. Our ability to hear specific frequencies is not like a "wall" in the sense that suddenly we hear 20hz where we could not hear 19hz. Rather, it is more of a gradual increase in frequency sensitivity at lower frequencies and then gradual loss in sensitivity at higher frequencies. We are most sensitive to sounds in the 500 to 8000hz range which just happens to be pretty close to the range of the human voice in "normal" conversation – go figure!

Anyway, STC is designed to emphasize that particular frequency range in its calculations and measurements. So, STC should be most "accurate" in determining performance in the frequency range involving human speech, and less accurate when used as a value involving higher or lower frequencies.

Okay, enough of that!

Per your original question, can you explain a bit more about the door "reverberate"? Can you actually see it move? What sounds are you hearing? Does the door "buzz?"

Stiffness is a good thing when you want to stop sound. The door can't be too stiff....something else is happening. The more details the better!

LowE and argon have no effect on sound propagation.

If you can provide a few more details, maybe we can see what's happening. :shock:

InfoSponge
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Joined: Tue Jan 17, 2006 2:25 am

#13 Post by InfoSponge »

You may also have a door that was improperly installed or manufactured. Your detailed answer to the question about the sounds you hear might help determine that. Mention whether or not you seem to hear only outside noises coming in, or if parts of the door itself also seem to be "making their own added noises" due to vibration from the outside sounds (loose screws, glass visibly shaking, trim rattling, door hardware/lock not secured in place, etc.).

Also, what size is the sliding door? It is a normal 2-panel door with one operating and one stationary panel?

bsedgwick
Posts: 13
Joined: Tue Feb 21, 2006 6:13 pm

Sound transmission through sliding glass doors

#14 Post by bsedgwick »

Thanks, Oberon and again, Info Sponge. All of this information is helping so much for me to begin to understand what the problem might be. Since the manufacturer appears at a loss about the problem it seems I am having to educate myself to become a part of the solution. I never intended to know this much about windows and doors but Voila!- here I am.

In answer to the question about what my wife and I are hearing (I have a 10% hearing loss and she has perfect hearing but we are both annoyed by the sound)-- the reverberation that I am referring to is a sound with a lot of vibration. If you can imagine talking into a pipe or a barrel, the sound has a distorted quality with a lot vibration to it. This is what the sound does that comes through the door. It is less irritating to open the door and just hear the sounds in their natural state (mainly traffic and airplanes). The door is a 6 ft sliding door with one fixed panel. If you tap on either panel the glass vibrates and sounds like you are tapping on a barrel. The fixed panel vibrates more when tapped. The previous door that was in this same jamb did not do make this sound.

The sound is variable and much worse at night. It happens in proportion to how much noise is going on outside and especially when the competing sounds of the day are absent. At night I would call the sound a droning noise- just a constant background of distorted sound. A buzz to me would be more constant but this sound varies with what sounds the environment is producing.

The glass is definitely not stiff. As I say, you can tap on it and easily see it vibrate. There is no apparent loose trim or screws.

We live in a townhome with units adjoined on both sides. Our townhome backs up to a golf course. There are a smattering of trees but not wooded. The nearest houses to our rear are about 150 yds. To our east about 200 yds is a six lane road. This road seems to generate the most noise. Airplanes sounds come in second place. The first night the door was installed we noticed the sounds- sounds we did not hear with the previous door.

Hopefully, this description will help. If you need me to elaborate on anything, I will be glad to. Thanks again,

Bill

Oberon
Posts: 119
Joined: Tue Dec 13, 2005 8:57 pm

more

#15 Post by Oberon »

Are you saying that the glass physically "moves" when you tap on it? You can see it vibrate?

Glass will move a little when tapped, that is normal, but I am under the impression that you are seeing more than normal movement.

Glass will vibrate with sound - that is also normal - but again I am sensing from your post that you are seeing - and hearing - something more.

Do you see any visual distortion towards the center of the lite? If you push on the glass at the center of the lite, what happens?

I am also assuming that the doors themselves are tight when closed and locked...no movement of the overall construction?

:? :?:

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