Oberon
10-31-2004, 07:50 AM
Good morning.
I am very new to this site, this morning as a matter of fact, and I was looking around at a few older posts and decided to respond to a couple.
But, after replying, I noticed that they did not go to the head of the class! Now, it is entirely possible that I messed up somehow...but, I am going to place my responses in new topic's for no other reason other than I hope that they begin an interesting discussion or two!
So, here goes the first one:
This is in reply to a question concerning dual versus triple pane windows. A number of the original respondents felt that triple pane was something of a gimmick and not worth the potential cost.
The original post here is quite old, but I am going to dig it up and make a couple comments if folks will bear with me.
First, triple pane is not a gimmick. Triple pane can be a good bit more efficient than dual pane provided a few criteria are met.
First, the really efficient parts of any window, dual or triple pane, are the spacer (the thing that holds the two or three pieces of glass apart), the application of a Low-E coating, and the inclusion of an inert gas between the lites.
The spacer may be made of several different materials, but the newer spacers available are all made to be called "warm-edge" in the industry. Warm edge includes TPS, SuperSpacer - which is primarily silicon, Swiggle - which is a foam product with a metallic core, Cardinal XL - which is a very thinwall stainless steel, and Intercept - which is also a stainless steel product with a foam coating.
So, all that means simply that a "warm-edge" spacer system makes for a warmer window.
Next, Low-E coatings. There are two types - hardcoat and softcoat.
Softcoat is better.
Hardcoat is basically a layer of tin oxide applied to the glass while it is still semi-molten in the float glass process.
Softcoat is applied in a vacuum chamber to "finished" glass in multiple layers of metals and metal oxides. One or two layers of silver is the secret behind softcoat Low-E.
A single layer of Low-E coating on the inside of an IGU (insulating glass unit) in a dual pane application makes the window MUCH more efficient than a triple pane with clear (no Low-E) glass. BUT, what if the Low-E coating is applied to two inside surfaces on a triple pane unit?
hmmmmmmm...actually works really well in that case.
Next, we have the "gas". Two primary gasses are used in IGU's, argon and krypton (okay, there are several variations, but this is already long enough!).
Argon is basically a byproduct and it is relatively inexpensive. Krypton is much more expensive, so for the most part, argon is used in dual pane applications. But, some companies offer krypton in triple pane applications and argon in dual...why?
Because of the nature of the two gasses, krypton is MUCH more efficient when used in a narrower space. Imagine a triple pane IG with two 1/4" airspaces between the lites. In fact, at that narrow width, argon isn't really that much better than air. BUT, krypton is actually at its peak efficency at that width.
Argon gets much better at wider spaces and at about 7/16" peaks in efficiency...which just happens to be a very common airspace width for dual pane IG's...go figure.
Krypton is still slightly better than argon at 7/16", but not enough to make using krypton worth the extra cost.
And I haven't even mentioned Xenon!
And, as always the quality of the construction and especially the installation cannot be overstated!
I am very new to this site, this morning as a matter of fact, and I was looking around at a few older posts and decided to respond to a couple.
But, after replying, I noticed that they did not go to the head of the class! Now, it is entirely possible that I messed up somehow...but, I am going to place my responses in new topic's for no other reason other than I hope that they begin an interesting discussion or two!
So, here goes the first one:
This is in reply to a question concerning dual versus triple pane windows. A number of the original respondents felt that triple pane was something of a gimmick and not worth the potential cost.
The original post here is quite old, but I am going to dig it up and make a couple comments if folks will bear with me.
First, triple pane is not a gimmick. Triple pane can be a good bit more efficient than dual pane provided a few criteria are met.
First, the really efficient parts of any window, dual or triple pane, are the spacer (the thing that holds the two or three pieces of glass apart), the application of a Low-E coating, and the inclusion of an inert gas between the lites.
The spacer may be made of several different materials, but the newer spacers available are all made to be called "warm-edge" in the industry. Warm edge includes TPS, SuperSpacer - which is primarily silicon, Swiggle - which is a foam product with a metallic core, Cardinal XL - which is a very thinwall stainless steel, and Intercept - which is also a stainless steel product with a foam coating.
So, all that means simply that a "warm-edge" spacer system makes for a warmer window.
Next, Low-E coatings. There are two types - hardcoat and softcoat.
Softcoat is better.
Hardcoat is basically a layer of tin oxide applied to the glass while it is still semi-molten in the float glass process.
Softcoat is applied in a vacuum chamber to "finished" glass in multiple layers of metals and metal oxides. One or two layers of silver is the secret behind softcoat Low-E.
A single layer of Low-E coating on the inside of an IGU (insulating glass unit) in a dual pane application makes the window MUCH more efficient than a triple pane with clear (no Low-E) glass. BUT, what if the Low-E coating is applied to two inside surfaces on a triple pane unit?
hmmmmmmm...actually works really well in that case.
Next, we have the "gas". Two primary gasses are used in IGU's, argon and krypton (okay, there are several variations, but this is already long enough!).
Argon is basically a byproduct and it is relatively inexpensive. Krypton is much more expensive, so for the most part, argon is used in dual pane applications. But, some companies offer krypton in triple pane applications and argon in dual...why?
Because of the nature of the two gasses, krypton is MUCH more efficient when used in a narrower space. Imagine a triple pane IG with two 1/4" airspaces between the lites. In fact, at that narrow width, argon isn't really that much better than air. BUT, krypton is actually at its peak efficency at that width.
Argon gets much better at wider spaces and at about 7/16" peaks in efficiency...which just happens to be a very common airspace width for dual pane IG's...go figure.
Krypton is still slightly better than argon at 7/16", but not enough to make using krypton worth the extra cost.
And I haven't even mentioned Xenon!
And, as always the quality of the construction and especially the installation cannot be overstated!