Imploding Argon windows ?

Ask replacement window questions & get answers!
Post Reply
Message
Author
snappytom
Posts: 3
Joined: Wed Sep 28, 2005 7:31 pm

Imploding Argon windows ?

#1 Post by snappytom »

Great forums .... first time post.

We are currently shopping replacement windows for our 30 year old house (16 Double Hungs).

While getting a third estimate yesterday the guy was telling me a story of how some older argon filled windows are failing by imploding. I said "that must mean there is a vacuum between the glass". He continued, saying that argon, being of very small molecules, is actually leaking out over time thru the glass itself. Air is composed of various gas molecules which are much larger and cannot penetrate the glass to fill the void, so the insulated glass implodes.

Now I consider myself an intelligent person, but I am not a scientist, chemist, physicist. etc.. I am having a hard time digesting what he has told me. I can only think that his manufacturer has a stockpile of non-argon filled windows that they want to get rid of and he will get a spiff for moving them.

Anyone heard of this ???

FenEx
Posts: 553
Joined: Thu Oct 07, 2004 11:18 am
Location: Illinois

Reply

#2 Post by FenEx »

Yes Tom.. it's a well guarded secret. Argon is an inert gas on the run!!!

Inert by definition means "sluggish in action or motion, lethargic or unable to move". It comprises about 1% of the Earth's atmosphere and is the third most abundant gas as it is a byproduct of oxygen and nitrogen.

When it dissipates from windows... it leaks through poorly designed seals, usually at the bottom of the windows (as it is heavier than air) due to sheer stress and the drying of sealants that are used with conductive spacers. Once the seal has been permiated, it's an easy mark for replacement air... hence the abundant use of desiccants in the spacers commonly used in the industry.

Now, if I am wrong, and your window dealer was right, I want you to immediately turn off and remove every light in your house as you and your family are in danger. Incandescent and flourescent light bulbs are also filled with Argon gas and made of much thinner glass.

THEY COULD BE ABOUT TO IMPLODE!!!

geoff
Posts: 12
Joined: Mon Sep 26, 2005 8:29 pm
Location: New Hampshire

#3 Post by geoff »

I know squat about windows, but this guy is blowing Argon up your you-know-what.

As FenEx has pointed out Argon is heavier than air which is mostly Nitrogen and Oxygen and being heavier the molecule/atom is also larger, not smaller than air. Check out this perdiodic table: http://wine1.sb.fsu.edu/chm1045/tables/ ... _large.jpg

N = Nitrogen (Atomic weight = 14.01)
O = Oxygen (Atomic weight = 16.00
Ar = Argon (Atomic weight = 39.95)

I presume that the extra insulation value occurs because gases have the same number of molecules per unit volume under a given pressure. Since Ar has over twice the atomic weight of air it is denser and therefore the molecules have more inertia which makes it more difficult for the heat (kinetic energy) to be transferred. This is also why Krypton fill has higher insulation value and I believe some skylights even have Xenon fill.

Kr = Krypton (Atomic weight = 83.80)
Xe = Xenon ((Atomic weight = 131.3)

Note that Ar, Kr, and Xe are on the same column of the periodic table, which means they have the same number of electrons in their outer shell. These gases are called Noble gases and, I hate to contradict FenEx, but they are called "Inert" not because of their mass (explained above) but because their outer electron shell is completely filled meaning that it is EXTREMELY difficult for them to combine chemically with other elements.

Finally, all this is actually irrelevant because if something is leaking from the inside to the outside or outside to the inside the two pressures will come into equilibrium. That means that there no pressure being exerted from the inside out or outside in. Therefore they won't explode or implode.

BTW, you won't be seeing any Radon (Ra) insulation in your windows any time soon. I'm sure they would perform fabulously, but unfortunately Radon is radioactive. :-)

Geoff

JScott
Posts: 508
Joined: Tue Jan 04, 2005 5:06 pm
Location: Kentucky

#4 Post by JScott »

Come on guys, I read all of that and never once found out what the half-life is of argon. :lol: Stop teasing us.

Guy
Posts: 552
Joined: Thu Oct 07, 2004 12:41 pm
Location: Minnesota

#5 Post by Guy »

Hey cool I learned I'm "INERT", thanks buddy!!! Good luck at the show this weekend!!

Oberon
Posts: 283
Joined: Thu Oct 07, 2004 10:25 am
Location: East of the Mississippi

imploding windows

#6 Post by Oberon »

Imploding windows is a real phenomenon. It does happen, although it is not particulary common.

Exactly as FenEx stated, the argon can dissipate through the seal (this is particulary evident when using organic seals or polysulfides, for example), but it is also quite possible that the physical mechanism that causes argon dissipation may not allow outside air molecules back into the IGU at the same time.

As Geoff stated, everything in nature wants to reach equilibrium, and with the environment inside the IGU containing an amount of argon greater than 1% and the environment outside the IGU containing less than 1% argon, then that argon inside the IGU and outside the IGU have a real desperate need to become equal.

(and btw, as an aside, scientists recently determined that they were wrong about how much argon is in the atmosphere..."Old measurements dating from as early as 1903 gave the content (moles of argon/mole of dry air) as 0.934 %. The most recent value available until now was lower (0.917 %) and was thought to supersede the previous result. The work reported in Metrologia gives a new figure (0.9332 ± 0.0006)%, very close to the measurement results of 100 years ago. The uncertainty in the new measurement is given at the 95% confidence limit and is of unprecedented accuracy." - :roll: - I borrowed that from a scientific paper).

The result is an IGU that can actually form something of a vacuum between the lites as the internal argon migrates thru the seal.

In many cases, the argon will never be missed - in the sense that there will be no particulary obvious change in the appearance of the unit. But, it is also possible for the glass to begin to become concave and for the two lites to "bow" into the center of the IGU. This bowing is usually related to the window size and aspect and also it can be related to the particular environment where the window is beiong used.

In extreme cases, the glass can shatter because of the stress of this bowing - or implode - which is the term most often used for this issue.

tru_blue
Posts: 223
Joined: Fri Jan 13, 2006 2:02 am

Imploding Argon Windows

#7 Post by tru_blue »

Old topic with a new insight. An interesting article on the subject from a few years back is at

http://www.usglassmag.com/Door_and_Wind ... /argon.htm

It essentially states that as argon gas leaks out throught the seals of IG units, air does not leak in to replace it, which as mentioned in previous posts can cause thermal stress, implosion, and distortion of the glass. Just an interesting FYI.

Post Reply