• Since this blog’s posted there, I’m obviously a follower of USGNN.com.™ It’s a great source of blog topics. One item of note was this one from April 16: China: “Glass Covered Towers Nearing Critical Age.”

    A quote from the original article in ChinaDaily reads as follows: “Glass curtainwall, in which a building’s facade is made of sheet glass held in place by framework, began to appear in Chinese blueprints in 1984, and have an average design life of 25 years. The durability of supporting parts, such as bolts and sealant, is generally 10 to 15 years.”

    Really? My initial reaction was, “where’s the Donald’s phone number?” I want to ask him if they told him this before he bought them there Chinese winders?

    I once worked on an upgrade of a curtainwall built before I knew what curtainwall was. Thanks to the bug in the corner of the spandrel glass, I learned the glass was manufactured the year I graduated high school. It was a reverse pressure wall—the I beam aluminum mullions were outside, the pressure plates were inside, and, yes, it did need to be re-gasketed since the neoprene gaskets were shot. But that was about it. The glass was almost 35 years old. Greg Carney was around (accuse me of being “old” at BEC—paybacks are tough, GC!) when IGUs were installed with thin gauge stainless steel channels around the perimeter of each lite—this job had that type of vision glass, and for the most part, it was still holding up.

    And then it dawned on me, the first paragraph in the ChinaDaily article mentioned the kicker, the maintenance probably hadn’t been done. When a job’s closed out, providing an owner with a detailed a maintenance procedure is both for his benefit and yours. If he doesn’t follow it, how does that impact warranty claims? If he does follow it, would you be willing to hire out and do the periodic inspections to support his maintenance program?

    It’s my impression that curtainwalls and windows generally should have a 35- to 40-year life expectancy when the proper products are designed and installed with realistic performance specifications AND expectations. But bolts and sealants that fail after 10 years, even 15? I guess they would if they were made to inferior standards.

    I’d like to think as an industry we’re still trying for the 35- to 40-year version here in the States. Wouldn’t that be an interesting selling point next time going up against a foreign competitor, especially the Chinese? Telling Mr. Owner the product you’re trying to sell has a 60 percent longer life expectancy than those of your foreign competitors. Wonder if that’ll get the owner’s attention, or is it all about the initial cost?

    I’ve got a dollar that says a lot of the condo issues with glass or poor-performing walls have something to do with VE (value eradication – not engineering) that goes on at the front end of a lot of projects. The end result is that the 25-year life expectancy model may not be too far off—and when the problems are discovered, the developer’s long gone. Any bets?

  • Does anyone really have enough energy to follow all the energy discussions floating around the blogs and magazines? If you missed it, USGNN.com™  ran a story on April 16 announcing that the City of San Francisco is about to require energy audits for buildings larger than 10,000 square feet. That’ll wake up some owners to the fact that their buildings can do better. This might be good for the glazing industry since many facades will require upgrades.

    Along these same lines, the March issue of USGlass had an article by Debra Levy titled “How the New LEED Will Affect Contract Glaziers.” Here are my thoughts about what might happen:

    1. Manufacturers are asked to verify the U-value of the wall during design development, which will mean marrying up with glass manufacturers AND framing systems much earlier than current practice. Heck, the whole paradigm of design, detail, bid, construct, commission, operate might all have to be changed. NFRC could be one avenue to do this; hopefully there are others.

    2. Looking harder at how glazing interacts with various sunshading devices (films, frits on glass vs. external sunshades) or wall insulation at spandrel/non-transparent glazing, and their impact on energy consumption will need to be determined.

    3. Window systems eventually might be rated by an industry standard for air and water penetration. Some would argue they are now, since the ASTM testing verifies their performance. But someone is going to want that on a label. When doing condo work, the air/water performance is critical, especially for doors and windows. This criteria might be given more consideration going forward.

    4. The code officials and architects will look to the manufacturers for a “whole warranty.” This will be tough to put on the manufacturers – who can design the details – but the glazing subs have to install them correctly. The associated warranties should be with the installation, not the manufacturers. Are the glaziers going to be ready to do that? You know the GCs aren’t going to accept it – they’ll want the subs to give the warranty. And the subs will look for the manufacturers to take it, who won’t, at least not at present.

    5. The only way I see the manufacturers taking on that liability is to have representatives onsite observing (or inspecting? – legally, there’s a difference) a given installation. Or are the manufacturers going to require “certified” installers? That’s still going to beg the question, but what if it’s not installed right, certified or not? It’ll be interesting to see how this plays out.

    6. On-site testing to check whole-wall assemblies may be coming, part of which will be air infiltration, hence the requirements above become critical. But instead of just testing the windows, the brick wall adjacent to the window might be checked. Heck, the whole building might be checked, which is where the Energy Star program for residences is headed. Think about that: the air exhausts over your stove, in the laundry room, in the bathrooms may require a mechanical dampener to open only when in use, and forcibly remain shut when not. I’d like to see how they isolate where the “extra” leaks are coming from, and which sub gets to correct what when that occurs. Now apply that same mentality to commercial buildings, there’s no telling where it ends.

    Your thoughts?

  • More than a year ago, an architectural firm asked us to help with the design/development of its contract documents because the firm was using one of our framing systems as the “basis of design” on a large public project. Since that kind of commitment would entail substantial upfront costs that might not be recouped, we asked if the firm would be willing to take the project off the street and handle it as a negotiated bid.

    In addition to incurring costs that might not be recaptured, a second concern was if we were to provide that service and the job was openly bid, we’d be so familiar with the project that most of the unknowns could be recognized and priced accordingly. That familiarity would be a luxury compared to those we’d be bidding against, since they wouldn’t have as much time to prepare their bids, and therefore wouldn’t be able to project the cost as accurately. However, that “luxury” might also make our price higher–give me 12 months to review a job before bidding and the number will be much more accurate than someone who only has 1/10th that time.

    It’s not much fun when you know you had a good number, and someone else gets the job with a significantly lower bid that might not be as accurate.

    Unfortunately, the owner of the above project would not allow it to be pulled off the street, so while we helped the architect with some detailing on a limited basis, we had the same opportunity to bid and review the documents when they eventually were issued.

    The reason I tell this story is there appears to be a fundamental shift away from the “conventional” bidding process in which architects design a building and prepare construction documents, general contractors and subcontractors review the documents to prepare bids, the bids get evaluated, and eventually a winning bid teams builds the project. At the end, it’s all turned over to the owner, who then operates the building based on the commissioning.

    This change may be afoot for a number of reasons, including the more widespread adoption of BIM, as well as energy efficiency issues. LEED is changing, the International Green Construction Code (IgCC) was recently completed, and these might also drive the development of a new procurement method.

    Architects are going to have to be much more selective with the products they specify, and the decision to select one product over another might not be based on upfront cost alone, but on cost and energy performance taken together. And that’s going to require the sellers, both glazing subs AND the manufacturers from whom they buy products to get much smarter not only about their costs, but what it actually takes to produce the material before it gets to them AND then operate the products for the life of the building. Energy requirements aren’t going to be as simple as, “What’s the U-value, the shading coefficient, and the solar heat gain?”

    The final selection of products is going to occur much earlier. A construction team might be put together as the architect is developing the construction documents, which would lead to much more “negotiated” work not open to public bidding. The general contractors who are selected are going to go to the subcontractors who they have successfully worked with in the past, and bring in only the products that have a proven track record of establishing and meeting or exceeding performance when it comes to energy. This team will evaluate all of these considerations in selecting a material.

    Once the manufacturers get clued into this, they may want to charge more upfront for a product that performs better (you’d pay more for a Porsche, wouldn’t you, than, say, a Yugo?). But since there’s a payback in lower energy consumed in manufacture or operation, the increased cost would thereby be justified, hopefully. That’s a thin line to walk, to increase the price, stay competitive in the marketplace, figure out whether the customer can afford it, etc.

    There’s possibly going to be an energy history kept as to how a project actually performs compared to the design. If you insulate your attic or update your windows, you see a lower energy bill. It’s simple in a house, but it’s more complex in an office building or school or hospital. I can foresee the architects adding that to their promotional literature; their designs are better from an energy performance level.

    But, can you imagine finding out in a year or two after a building begins operation that the curtainwall’s not performing up to expectation? I don’t know how the actual fenestration performance is determined in a commercial construction setting, so that’ll be something else interesting to see how it shakes out. Daylighting can be measured, but the question is, is the real-world performance in-line with what the designers envisioned? How about all the other criteria?

    Or, is it sort of like the mileage sticker on your new car? No one really expects to actually get the MPG posted (and isn’t that a shame – the car manufacturers blame it on the Feds; a whole other blog could be written on THAT particular topic). What if after you bought the car, you could sue the manufacturer because it didn’t perform?

    What are the specific design and specification changes that might come about from LEED and IgCC code changes? I’ll save that for the next blog entry. In the meantime, I’d be interested in hearing your thoughts on anything else besides energy that might lead to a procurement methodology shift.

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