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?