1. Introduction

In reviewing the docket on the subject of sealed insulating glass units the other day, I found that as far back as mid-1964, shortly after I started with FHA, several of our field offices had expressed concern and asked for guidance in selecting suitable sealed insulating glass units.

The increase in the number of manufacturers and types of manufacture, coupled with the absence of a way to evaluate the performance life of these units, amplified the need to pursue efforts toward some type of solution. This was added to our list of project assignments in March 1965.

2. The Need for a Test Procedure

FHA has reviewed various specifications for evaluating sealed insulating glass units. There were, and still are, differences of opinion on a procedure which can be successfully used. Our interest, of course, is in a procedure to measure (estimate) the service life (durability) of these units.

Large areas of glass are used widely in today's architecture, and as the consumer demands further sophistication in the control of his environment, the additional comfort provided by sealed insulating glass units will result in increased use of these products.

One generally considers glass to be a very dur

1 Architect, Architectural Division.

able building material; excluding breakage, it is one of the few products capable of lasting the useable lifetime of a building. Based on the foregoing premise, it would indeed be tragic to discover suddenly that unanticipated failures necessitate replacement.

The Methods and Materials section of FHA's Architectural Division is responsible for providing our field offices with the best technical advice possible and in many ways is comparable to the specification department of an architectural firm. When there are concerns about product performance, ways and means must be devised and measures taken to provide protection commensurate with the estimated risk.

During the next two days, we will all have the opportunity to review and discuss various methods used to measure or estimate the durability of sealed insulating glass units.

For several years FHA has been trying to determine if there is one test method for insulating glass that can be depended upon for estimating service life. If there is a margin of error in using such a method, what percentage of success can be expected? In view of the fact that there is uncertainty about an acceptable test method, we can understand why specification writers sometimes use empirical precautionary measures.

It may be advisable for FHA to consider reserves for replacement of units that fail in programs where such reserves are required. In regard to single family programs there are no reserves; consequently, the homeowner will face the expense of replacing these units on his own.

3. Conclusion

Several articles have been published in recent months relative to the liability of the architect, engineer, and manufacturer in regard to building materials and systems. Who is to be placed in the position of ultimate responsibility? The architect who makes the selection? Or the manufacturer who has offered evidence of performance for his product?

The selection and use of new materials and systems could be seriously deterred by attempting to single out a source of responsibility.

It would seem to me more logical to think in terms of a team effort whereby responsibility is reasonably distributed and ultimately placed. I believe if we can show that we have exercised the best of our current knowledge in arriving at such decisions, such as by selecting an appropriate test. method, then we will be able to endure criticism. that may arise from our decision.

If we share an interest in development and innovation (in other words in progress), then we must share in assuming the probable risk and responsibilities of this adventure.

1. Introduction

I think it is important to make one comment before I get into my discussion. Much of what I have to say is equally true of many, many other building products so I'm not taking a potshot at the insulating glass industry.

The major problem with regard to durability, other than accidental breakage, is the failure of the seal with its attendant and very attentionproducing element of fogging or vision-obstructing moisture. Due to limited time, I won't go into detail on the topics but I believe you can break the builder's viewpoint down into two categories involving periods of time: The first, you might call the short term, which would be the time when the house or the building is under construction or if there is a one-year warranty period. And the second, the longer term, is when the unit is under the manufacturer's warranty.

2. Failure Problems

The short term problem presents the builder with a number of questions rather than answers, and these concern how meaningful the warranties are. In other words you have a 5-, 10-, 20-year warranty. . . are these warranties really indicative of the expected life of the unit, and are there meaningful test procedures to back up these warranties? When a builder purchases an insulating unit, how does he know what he's really getting? Of course, as with any other products on the market, he pretty much has to rely on the manufacturer. Let's assume that during the time when it's the builder's responsibility, that a unit does fail. Now what can the builder expect to happen? Well typically the manufacturer will replace the unit.

1 Assistant Director of Technical Services.

This is only a partial answer because the builder still has to take it down to his dealer, bring it back, and reinstall it. Therefore, merely replacing a unit that fails does not compensate the builder for all his costs. I think this is really the most. important aspect of the problem because the warranty doesn't really protect the builder insofar as his total cost is concerned, and therefore it in itself is not a completely adequate means of re

course.

Now to take the longer range aspect, where the unit is now under the manufacturer's warranty. As far as we are concerned, there is a single problem in this area. If a unit does fail say after 2, 4, or 5 years, who gets the blame? Well, I'm sitting here, and because the buyer bought the house from me, I'm responsible to that buyer. And I'll tell you, this is not a very satisfying answer to give to one of your buyers "Well, it's not my responsibility any more, you have to go see the manufacturer." So, in effect, the builder's public image suffers as a result of this. Now I think it's important to realize for this particular aspect, that the average home mortgage today is slightly over 7 years, and this means that repeat business to a home builder is equally as important as it is to any other business, and the manner in which the manufacturer backs up his product is extremely important. I think the fact that the glass unit is typically manufactured by someone other than the window manufacturer has a tendency to compound the problem.

3. Conclusion

Now the question is: What are some of the conclusions or solutions to this problem. I have made a short list, and they are not necessarily in order of importance, but I thought I would put them forth to you.

First is an establishment of appropriate standards and test methods. Second would be a certification program. Third would be the issuance

of adequate installation instructions, which I believe Mr. Rosen briefly commented on, as to how to properly install and where not to install such windows. I think in general there has to be a method of evaluating existing products that are on the market. This won't go over very big, but I think that the solution to the failure problem, from the builder's standpoint, is that perhaps the manufacturers and the dealers should consider

some method of servicing, or at least evaluating, failures on the job site, particularly with regard to establishing responsibility as to whether it was improperly installed, improperly manufactured or whatever the case might be. And, in addition, I believe that the producers of glass, and the window manufacturers should cooperate to the fullest degree to produce a window unit that will give the desired end results.

Mr. McKinley: Thank you, Mr. Rosen, Mr. Snell, and Mr. Bryant. You have presented a challenge. We hope to develop a fruitful response from the audience.

I would like to have a question put first to Mr. Bryant since his comments are most recent and fresh in your mind. A second question to Mr. Snell. A third question to Mr. Rosen. Having those questions presented we'll all adjourn for coffee. That will start what Mr. Rosen referred to at breakfast as "the fracas". Who has a question for Mr. Bryant? Yes sir? The question: What are the builders doing to evaluate units? The second question, this one for Mr. Snell (FHA). Yes sir? The question: How are insulating glass units now being selected? Thank you very much. Coming from Canada I think it's very important because they do have a unit testing system. I hope you'll talk about that with Mr. Snell also. Now who wants to present a problem to Mr. Rosen. Yes sir?

Clark D. Moore: I'd like to ask Mr. Rosen what his criteria are for using insulating glass with reflective coatings as opposed to just standard reflective glass?

Mr. McKinley: A very perceptive question. I think most of you know that there is something new in the insulating glass market referred to as a reflecting unit. That's an excellent question for Mr. Rosen.

Mr. Bryant, I wonder if you'd care to give us your response to the question put to you earlier.

W. Bryant: I believe the question is, "What have the home builders done to evaluate insulating glass units?" There is no easy answer to this and I am not trying to be evasive at all. You in the glass industry have one product with which you are concerned. I don't think anybody's ever taken the time and effort to tabulate the total number of different products that go into housing construction so the answer to the question as to what we have done is, quite frankly, "nothing in the way of research." Now we do have a research foundation which is a totally owned subsidiary of NAHB and which does research into products built for us and for manufacturers. But I think really the solution is that there has to be a much greater dialogue between the builder, the dealer, the manufacturer, supplier, etc., as to where the problems lie. As a National Trade Association, we only hear of the problems that are told to us. If we had received an enormous number of complaints about insulating glass quite possibly there would have been a research project by this time. As I say, it's very difficult to give you a definitive answer to your question but I think that everybody needs to really get together and discuss the entire issue, and this is true for many products. I think we often fail to appreciate the viewpoints

and the problems of each other with regard to any product.

Mr. McKinley: Thank you, Mr. Bryant. Mr. Snell.

Mr. Snell: Very briefly, I believe the question was, "How do we now select units?" and I think I can limit my answer to "Hopefully".

Mr. McKinley: Thank you. I think that is understandable to all of us. Mr. Rosen.

Mr. Rosen: I think the question that was posed was "What are the criteria for using insulating glass with reflective coatings, as opposed to just standard reflective glass?" I think that the answer to that question, and to all questions of that same nature how do you make a determination of a material to use-depends upon what the industries themselves have done. When there are standards available for the specification writer to use in the determination of whether a material meets an ASTM standard, a Federal specification or a USASI standard, he utilizes them, and if he wishes he can modify them too. But he has a basis for making some sort of a decision that is concerned with an industry acceptance of a specific standard. We're now dealing with a product for which we have no standards whatever. Hopefully, our Canadian friends and our Norwegian friends may have some answers for us with respect to the type of criteria that should be established for insulating glass and for insulating glass having reflective coatings. This would perhaps be the start or the basis for the beginning of a standard somewhere, promulgated by ASTM or USASI or some other organization that has an interest in developing that kind of a standard.

Mr. McKinley: Thank you, Harold. May I ask that you continue the discussion over coffee, or at lunch or dinner with all of the speakers. We do thank you three for your contribution. You've launched this Seminar most effectively.

Mr. McKinley: Earlier we mentioned formal technical sponsorship of several well-known organizations. I think it's significant that our audience includes a heavy representation of fabricators of insulating units from all over the world with specific emphasis on fabricators from Canada. Following the next paper, because they've had specific experience, we will ask them to comment as specifically as they can, and, with as much vigor as they care to, about their Canadian experience.

The next paper is entitled, "The Development of Evaluation Procedures for Factory-Sealed Double-Glazing in Canada." The authors are Mr. A. Grant Wilson, Head, Building Services Section, National Research Council of Canada, and Mr. K. R. Solvason, Research Officer, Division of Building Research, National Research Council of Canada. Mr. Solvason will present the paper. Following his presentation, there will be an opportunity for discussion.