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.