Reinforcement of Larger Windows

[mermaidcean]

First let me start off by saying I own and have read (multiple times) SGAA Reference and Technical Manual Chapter 5 on Structure and Reinforcement. I have researched so many hours on this subject. I know the standard rule is 12 sq ft. I know the new rule is 14 linear perimeter feet. I also know it depends on the shape of the design. The problem is, I see panels everywhere that do not appear to follow these guidlines. There are panels in The Stained Glass Quarterly, panels in professional stained glass books, and panels in home improvement magazines. All of which are of considerable size without any apparent extra reinforcement.
I am constructing large architectural designs (in lead). I always use the guidelines I was taught and have researched. Am I missing some secret that everyone else knows? I feel restricted in my designs because of using reinforcing bars or mullions. Does the rule apply to copper foil as well as lead? I have a person here in my state that is very popular. He only does copper foil. The last panel of his I looked at was 4ft wide and 7ft high. No reinforcment what-so-ever! Some of the pieces inside were 3ft x 1.5ft. Am I crazy? Can I go bigger in my designs without reinforcement because all my designs are triple paned?
 I've only been doing this for 10 years but I'm trying to do it right. I would appreciate any opinions or comments on this topic.

[Vic Rothman]

There are NO hard and fast rules. A window can be 12"x12" and need support, while a window 3'x3' may not. It all depends on the design and placement of the window. A free hanging panel may not need support while the same design in a door probably will warrant support. The size limitations  are of a practical nature as much as anything else. You need to able to move the windows while working on them and installing them.  Any window will last a few years regardless of how it's made. But over time the materials start to fail due to various reasons. So the stronger you build the window, IE. design,size rebar, the better the chances are for long term survival of the window.

[Richard Gross]

It should be pointed out that the idea of panels needing reinforcement if they are larger than 12 square feet and 14 linear perimeter feet are good guidelines, but one does not replace the other. There isn't so much and old and a new rule, as much as both are worthy guidelines.

[Vic Rothman]

It should be pointed out that the idea of panels needing reinforcement if they are larger than 12 square feet and 14 linear perimeter feet are good guidelines, but one does not replace the other. There isn't so much and old and a new rule, as much as both are worthy guidelines.

The problem with the "guidelines" is that they imply that windows less then the given sizes do not need reinforcement. This is NOT necessarily the case.

[Richard Gross]

The problem with the "guidelines" is that they imply that windows less then the given sizes do not need reinforcement. This is NOT necessarily the case.

And so your proposal, then, is that all "guidelines" should be thrown out because they do not cover all possibilities? An exception -- even a hypothetical one -- somehow invalidtes all applications of a guideline?

Doesn't sound like a very good idea to me.

[mermaidcean]

Any answers on the copper foil or triple-paned questions?

[Vic Rothman]

The problem with the "guidelines" is that they imply that windows less then the given sizes do not need reinforcement. This is NOT necessarily the case.

And so your proposal, then, is that all "guidelines" should be thrown out because they do not cover all possibilities? An exception -- even a hypothetical one -- somehow invalidtes all applications of a guideline?

Doesn't sound like a very good idea to me.

there is nothing "hypothetical " that windows smaller then those stated in the guideline often need reinforcement. I've seen it many times

[Richard Gross]

there is nothing "hypothetical " that windows smaller then those stated in the guideline often need reinforcement. I've seen it many times

While it is very tempting to say: "Great! Cite 'many' instances, then," the fact is that I don't doubt for a minute that there are exceptions to this guideline. That's why there are also guidelines to inform good design and there are guidelines to inform good craft technique, and there are guidelines to inform many decisions that people make every day. For those of us not fortunate enough to have been born knowing everything, "guidelines" are excellent "lines" to "guide" our decisions.

[Vic Rothman]

there is nothing "hypothetical " that windows smaller then those stated in the guideline often need reinforcement. I've seen it many times

While it is very tempting to say: "Great! Cite 'many' instances, then," the fact is that I don't doubt for a minute that there are exceptions to this guideline. That's why there are also guidelines to inform good design and there are guidelines to inform good craft technique, and there are guidelines to inform many decisions that people make every day. For those of us not fortunate enough to have been born knowing everything, "guidelines" are excellent "lines" to "guide" our decisions.

The original poster wrote "First let me start off by saying I own and have read (multiple times) SGAA Reference and Technical Manual Chapter 5 on Structure and Reinforcement. I have researched so many hours on this subject. I know the standard rule is 12 sq ft. I know the new rule is 14 linear perimeter feet."  . They say they "know the standard rule" That would mean that they interpreted the "guideline" to be a rule, as to how to use reinforcement. All I said was that there are lots of variables to reinforcement and that there is No set rule. Each job has it's own nuances. We therefore need to be flexible in our approaches to stained glass fabrication.

I am a bit perplexed at your statement "For those of us not fortunate enough to have been born knowing everything, "guidelines" are excellent "lines" to "guide" our decisions. ". You are not suggesting that I was born knowing everything? If so I would like to point out that I've been working with glass  for nearly 40 years now. During that time I sold items at craft show, managed a stained glass retail store,taught classes,was the foreman of a restoration studio and have had my own studio for over 18 years. I have  100's of stained glass books (that I've read), have attended conferences all over the world and my work has been featured in the Stained Glass Quarterly twice. I was not born knowing everything. I worked very hard to learn my craft, and still do not know everything.

[Richard Gross]

Don't take things so personal, Vic. Nothing was aimed at you.

I, too, think the original poster is to be commended for spending time learning his craft. Anyone who owns the SGAA's Reference & Technical Manual and returns to it often should be well equipped to handle many of situations that he encounters. Such a person is also well equipped to know that the "rules" are typically "rules of thumb," or guidelines, and not mandates to be followed slavishly.

I'm also aware of your qualifications and know that you, too, have spent many hours learning your craft. Since we can both readily agree that you weren't born knowing everything but had to learn what you do know from many sources, surely we can also agree that your learning process involved encountering many "rules of thumb," or guidelines, and adapting them to the way you work and, therefore, you -- through your 40 years of experience -- are well-equipped to recognize the value of good guidelines.

I think we can also readily agree that each job does indeed have its own nuances and that we need to be flexible. Of course we will also agree that no one can operate in a vacuum; every decision made -- the very basis of flexibility is -- informed by the body of experience that we posess, which is distilled into the guidelines under which we operate. To devalue a given guideline, especially one so universally recognized as being based on many, many years of cumilitive experience within the craft, is to devalue the experience itself, which is counter to reason.

So, Vic, now that we've established the value of solid guidelines, I invite you to demonstrate also the value of your years of experience (not to mention have the last word on this topic) by offering the original poster worthy guidelines that will address his original question regarding copper foil and triple pane glazing.

[Vic Rothman]

Don't take things so personal, Vic. Nothing was aimed at you.

I, too, think the original poster is to be commended for spending time learning his craft. Anyone who owns the SGAA's Reference & Technical Manual and returns to it often should be well equipped to handle many of situations that he encounters. Such a person is also well equipped to know that the "rules" are typically "rules of thumb," or guidelines, and not mandates to be followed slavishly.

I'm also aware of your qualifications and know that you, too, have spent many hours learning your craft. Since we can both readily agree that you weren't born knowing everything but had to learn what you do know from many sources, surely we can also agree that your learning process involved encountering many "rules of thumb," or guidelines, and adapting them to the way you work and, therefore, you -- through your 40 years of experience -- are well-equipped to recognize the value of good guidelines.

I think we can also readily agree that each job does indeed have its own nuances and that we need to be flexible. Of course we will also agree that no one can operate in a vacuum; every decision made -- the very basis of flexibility is -- informed by the body of experience that we posess, which is distilled into the guidelines under which we operate. To devalue a given guideline, especially one so universally recognized as being based on many, many years of cumilitive experience within the craft, is to devalue the experience itself, which is counter to reason.

So, Vic, now that we've established the value of solid guidelines, I invite you to demonstrate also the value of your years of experience (not to mention have the last word on this topic) by offering the original poster worthy guidelines that will address his original question regarding copper foil and triple pane glazing.

The same logic for reinforcing a leaded window should apply to foiled windows as well. Of course there are some techniques unique to foil work. Such as the insertion of "restrip" or "strong line" between the glass pieces as you assemble the window.
The part of the original question about large pieces of glass and non existing support. All I  can say is many people like to push the envelope without knowing what the envelope is.
As for triple  paned glazing. This is something that I have never done and therefore can offer no opinion. The only advice I give is from personnel experience.

[Dave Olson]

The problem with the "guidelines" is that they imply that windows less then the given sizes do not need reinforcement. This is NOT necessarily the case.

And so your proposal, then, is that all "guidelines" should be thrown out because they do not cover all possibilities? An exception -- even a hypothetical one -- somehow invalidtes all applications of a guideline?

Doesn't sound like a very good idea to me.

I don't see how Vic's statement, "NOT necessarily" implies that the guidelines should be thrown out. The impression I got from Vic's comments was that the guidelines may not be addressing reinforcement issues in smaller panels. "NOT necessarily" is a comment that indicates that some thought and careful consideration may need to be applied ... over an above what the guideline suggests. Forums like this are an excellent place to get many different responses to different problems. Defensive and slightly aggressive responses tend to scare away possibly valuable information.

If this forum site had a sound it would be a big empty room with a cricket chirping in the corner. Perhaps there are reasons for this.

Good Luck
Dave

[JRDurr]

Many of my windows use a combination of external support bars as well as interior support bars that I purchase at Biendheim. I may have the spelling incorrect, but the lead is from the Busher Company in Germany. Vic's comments are correct. We all have seen huge windows' ie 54"x120" ,without lap joints, containing a few 1/2" round bars with copper ties, and the window is holding up well for the better part of 100 years.
Copper foiled windows utilize fins as well as copper wire soldered to the foil. I suggest you look for some Tiffany style windows from the turn  of the century.
There is an excellent Tiffany show that is just closeing in Montreal and will be opening soon in Richmond VA.
A guide line is a guide line. It is not the end all to be all, but is not to be ignored foolisly.

Good luck.
JRDurr

[glassheritage]

I have to agree with both Jerome and Vic ... guidelines are exactly that, lines that guide us in making informed decisions ... I too applaud 'mermaidcian' for dilegently doing the 'homework' ... reinforcement, internal or external, foil or lead, lap joints or not, are, and should be determined by the structure of the specific panel, whether 12 sq" or 12 sq', knowing what to look for and assessing the need is a product of knowing the guidelines ...

[Richard Gross]

John, I see that you agree with Jerome and Vic and then quote me, so I suppose you agree with everybody. Great! I'm not sure why there would be any disagreement regarding the value of good guidelines. After all -- as you just said and as I said six months ago -- guidelines are lines that guide us in making informed decisions.

However, I really think all that can or should be said regarding guidelines has probably been said. I would like to see the conversation refocused a bit on the original question. The poster asked specifically about "reinforcement of larger windows." The topic is not and never has been exceptions found in smaller windows. While that would make a worthy and interesting topic in its own right, that is not the information the poster was seeking.

The poster wrote in part: "I have researched so many hours on this subject. I know the standard rule is 12 sq ft. I know the new rule is 14 linear perimeter feet. I also know it depends on the shape of the design." I responded to that as follows: "It should be pointed out that the idea of panels needing reinforcement if they are larger than 12 square feet and 14 linear perimeter feet are good guidelines, but one does not replace the other. There isn't so much and old and a new rule, as much as both are worthy guidelines."

I stand by that; there is not an old rule and a new rule, but there are two good guidelines. Are there exceptions? Certainly.
 
While I enjoy a good debate with Vic, the fact is I know him and I respect his work and his ability. I feel like I can debate with him because I believe him to be intellectually capable of holding his own in such a debate and of effectively making his point; he has certainly always shown himself to be so. It is unfortunate that someone might misunderstand such a discussion and while I would certainly enjoy a similar debate with you, John, in the interest of avoiding further misunderstanding I would suggest that it might be wise at this point to re-read the original post and answer it directly.