• When asked if we can solve a problem, most of us in the glass biz try to find a reasonable solution. I was recently told that Bill Lear (of Lear Jet fame) would fire any employee who told him, “that can’t be done.” What I think he was looking for was, “What are the options? Then, we can talk about what is realistic or reasonable from a cost or schedule standpoint.”

    Think back to IBM’s stock answer No. 3 from an earlier blog: “We can do that, but it will come down to how much time and money you want to spend to do it.” I’m not being facetious, but if an owner was willing to pay for gold-plate mullions, we’d do that. Wouldn’t your company do all it could to meet a customer’s expectation, if they were reasonable and were willing to pay the cost?

    Or, to shorten a schedule, we’d air-ship the material to a jobsite. If the cost for that wasn’t in the estimate, then the cost/benefit would have to be weighed:  if we don’t get it there on time, are there penalties incurred that are more severe than the cost of air-freighting the material? That’s an analysis that has to be determined for any given situation.

    Bringing new products to market is like that, too. The people in research and development vet all the processes for the typical applications, come up with all the parts, make sure the production team can actually manufacture the parts, then work with the installation folks to confirm all of those processes work. Then, when introduced to the market, someone is bound to say, “that’s the product we want to use, but can it do this?”

    A hypothetical situation that will bear this out: a customer brings a project to you that has a curved curtainwall. And, “they don’t want it segmented,” which, of course, is everybody’s initial response, right?  The curve can be in plan or in section—it doesn’t matter. They want to use a standard system to do this, say a pressure plate system, out of a really deep mullion section. So, in thinking about this, some of the problems that have to be dealt with include:

    1. Can all of the members be curved? That includes the mullion, pressure plate and cap, and don’t forget the glass. In the case of the cap and pressure plate, will the snap still function after curving?  Or will the bending tolerances be such that snap functionality is lost?
    1. In rolling the mullion, is one of the walls stretched too thin during fabrication that its structural properties are unacceptably reduced?
    1. What is the tolerance of all the parts, including the glass, when it comes time to assemble them? And, how are any tolerance extremes to be handled between any two parts? When one part is to the extreme plus side of its tolerance, and the one next to it is at its extreme minus side, so that when together, they’re as far apart as can reasonably be expected, what happens?

    So, if you can make sense out of all that in theory, do you take on that work? What are the costs? Can you manage all the coordination that will be required? Can you sell it? Does the decision-maker understand that the application can’t be sold for a standard wall price?

    Usually “we can’t do that” is replaced with a response that’s based on experience. Some of these aren’t shared with the customer, but are discussed internally. In the extreme, rare instances, this could include: We choose not to provide that because we tried to do it in the past and lost our shirt trying. Or, based on that past experience, we now know it’s so difficult to do, we don’t want to do it again.

    Explaining to customers those constraints helps them understand the costs associated with proceeding. What have your experiences been in this regard?

    As someone who likes artistic drawings, M.C. Escher has always been a favorite. Just because you can draw it doesn’t mean it can be done. I guess Mr. Escher never worked for Mr. Lear. Sometimes, Mr. Lear, it can’t be done, even if it looks really cool on paper!

    Credits for this blog topic go to Ron Madeley at TGP, for his stories at lunch and the Escher reference. And, happy birthday to No. 1 son, Jeremy, who in the past month became a father himself. Congrats, and hold on, you’re in for a heck of a ride: love every minute of it!

  • As I started to write this blog, I noticed the date it’s to be published: 9/11. As a kid, I never understood how Pearl Harbor could move my parents’ and my grandparents’ generations into fighting a war. After 9/11, who could ever question that motivation again? I hope we’ll always remember the price paid that day, and many days since, for our freedoms. God bless the good, great, the fortunate U.S. of A. I’m grateful to live in this good land.

    Okay, back to glass. At one time, anyone who had been in the glazing biz for very long had either worked for Cupples or PPG. Those two companies were responsible for everything from the monster towers of the 1970s in Hong Kong to the Twin Towers in New York to John Hancock and Sears Towers in Chicago. At that time, they were the equivalent to what Harmon, Enclos and Permasteelisa have become today. On the glass side, LOF and PPG were what Cardinal, Guardian and Viracon are now.

    It was with some sorrow I read an article about PPG getting out of the glass business. The story pointed out how much higher the overhead and initial investment is in making raw glass, as opposed to PPG’s chemical and coating product groups, where they will now focus their efforts.

    We all used to want to grow up to be PPG. In our eyes, PPG had the best of several worlds: they had a contract division that probably got a huge price break on glass, and they had an aluminum extrusion business.

    This history was brought into focus this summer reading an article in the June 2014 issue of USGlass about PPG Place’s 30th anniversary. The curtainwall system in that building was pretty interesting, as seen in this mosaic display of the corners and typical verticals (hanging in CDC’s Dallas headquarters).

    Photo courtesy of Charles Clift, Curtain Wall Design and Consulting.

    The PPG Place curtainwall was straightforward, and anyone who worked on it back then could probably pick it back up again tomorrow. It had many benefits:

    1. The basic frame members weren’t finished – so the shop and field could be a little sloppy in the handling of the basic frame components;
    2. The interior covers provided thermal separation from the exterior metals, and only these covers were finished;
    3. It was erected and glazed from the floor, minimizing the need for stage time; and
    4. Reglazing vision lites could be done from the interior.

    Bob Johnston, CDC founder, developed the PPG system “from his standard stick wall with collaboration from Gary McKissick, Bob Wheeler and Lloyd Stokes of PPG,” according to Charles Clift, senior principal at CDC (who was engineer of record for the curtainwall). He also recalls that “Phillip Johnson, the architect, required stiffness criteria that were twice as strict as normal industry standards of L/350 and max 3/8″ deflection” and that there was a need for an “unsymmetrical bending analyses on mullion shapes at corner conditions as wind load vectors did not align with extrusion principle axes.”

    PPG will be missed, if they do get out of the glass business or greatly reduce their role.

    As Bill Swango used to say, “be careful of whom you’re envious.”

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  • Many of us don’t often think about a building’s exterior skin after it’s installed. But, this set of pictures of eye-catching buildings around the world getting spruced up grabbed my attention, so I had to share them. Image 14, with the workers on the top side of a giant sphere, got me to wondering how close together the tie back buttons are.

    Seeing all those people in high places reminded me of when my grandfather used to tell us kids about the time he jumped off a 100-foot ladder and lived to tell about it. We’d asked him about firemen’s cushions, pools of water, etc. Then, he told us the punch line: he had jumped off the bottom rung. Unfortunately, that’s not an option for people working on hanging window cleaning stages. Another bit of relevant grandfatherly advice he gave me when I helped paint his two-and-a-half story home came to mind: “Don’t step back to admire your work.”

    About the only consideration many building skin design and building pros give to the exterior equipment is the type and placement of tie-back buttons and/or the tracks in the vertical members to accommodate window washing equipment. Such buttons and tracks help keep equipment and crews close to the building during cleaning, for safety. They are NOT meant to support the full weight of people or equipment. Contracting crews might also rely on the buttons and tracks during glazing, including hanging anchors, installing sealants, etc.

    YouTube has some great videos of hanging stages that got away in windy conditions. Tracks or retention buttons would have helped prevent that accident from occurring.

    Just like nearly every other profession, window washers have a trade organization: the International Window Cleaning Association (IWCA). The organization describes itself as the “secratariat of the ANSI/IWCA I-14 Window Cleaning Safety Standard, which is referenced by building owners and property managers as well as the Occupational Safety and Health Administration (OSHA). In addition, it was designed to also be referenced by professional engineers, architects and manufacturers of window cleaning equipment. The I-14.1 Window Cleaning Safety Standard is the only standard of its type that is specifically for those in the window cleaning industry.”

    Designers typically reference the I-14 standard in curtainwall and exterior skin specifications. They also usually include in the performance criteria section of those specs, data on the loads imposed by the window washing equipment that must be accommodated by the curtainwall or windows. Such loads are not more important than wind load or seismic drift, but are equally weighted and tested typically during full-scale performance mockups.

    I’m grateful that I don’t work hundreds of meters off the ground on the exterior skins of a building and instead have a safe desk with four legs on a level floor, no wind gusts and sun only through windows, not directly exposed to it or reflected off the coated glass. I don’t get on one of those window cleaning stages very often, for the same reason I don’t like hanging roller coasters or construction site personnel/material hoists – there’s a great deal of comfort to be found in a solid floor underfoot.

    Did you notice, looking through the extreme window cleaning pictures that many folks were wearing full-body harnesses? And, did you see some weren’t wearing them – are they crazy?

    A bit of (unsanctioned) advice to window cleaners: along with wearing a full-body harness and practicing safe scaffolding, take a hammer with you when you climb on one of those bad boys. If you happen to get caught without the stage underfoot, the hammer is the means by which you can get into the building. A change of clothes is optional. If you’re still alive, it’s all good, right?

    Lastly, kudos to the people who make our walls, windows, and glass look good long after we’re done installing them. Don’t know how you do it, day-in, day-out, but my hat’s off to you.

USGlass Magazine

USGlass Magazine