post construction window cleaning

We get many calls to clean windows after construction.  Oftentimes they are concrete tilt-ups such as these…  I want to discuss the best way to approach these buildings, which has been a philosophy 9+ years in the making.

I would suggest to a potential client that we should start with a basic wash which utilizes a water fed pole (long extension pole with pure water feeding inside the tube).  The water we use is a good cleaning agent since it is filtered from all minerals that cause water spotting.  It’s actually filtered on site as we have carts that we built that turn tap-water into spot-free filtered water through a process call reverse osmosis.  The advantages are several since we can work faster, safer and more thoroughly with higher levels of quality control.  The cleaning action is performed with the nylon bristled brush and the pure water coming out of the brush rinses the water-soluble dirt and residue from the glass.

The only problem is that we often encounter other debris that isn’t water soluble such as: paint overspray, concrete mortar, silicone, window decals etc that are more stubborn (called non-water soluble debris).  These situations require one of the following: razor blades (frowned upon due to scratched glass concerns),  scrubbers like #0000 steel wool (time-consuming), and/or strong chemistry to melt or burn the debris away (such as solvents or acids).  Neither of these options are ideal, but neither is life.  So our philosophy is simple…
Let’s start with a basic wash using the pure water/water-fed-pole for all water-soluble debris since it’s safe, non-damaging/invasive, and is very cost-effective. We call this Phase 1.

If after reviewing Phase 1, you or your client want further/more detailed cleaning with any of the other options, then we can proceed with a higher sense of clarity of what that project actually requires.  This is because after a good pure-water cleaning, we can actually see (properly diagnose) what’s still on the glass that requires further attention.  I’ve often found that much of this stubborn debris isn’t even visible during a job walk since
(1) job conditions (glass conditions) on construction sites are often changing daily
(2) there is often so much dirt on the glass that you can’t see some of the lesser visible debris hiding below a thick film of dust and dirt.
(3) as you know, every owner or project manager has different needs and expectations so why not start with the path of least resistance?

Naturally, the interior windows is done via a traditional soap and squeegee methods with detail rags but we won’t use abrasives unless we have written authorization.  Believe me when I tell you, I have seen the damage that can occur from excessively aggressive cleaning methods.  I’ve been called in on several projects after superintendents where informed that the last window cleaner used a razor blade on all the glass and half of it needs to be replaced due to the scratches it left behind. The risk really is fairly minimal but the cost for failure is extremely high (I’ve seen six figure damage on a new building). It really is a wreckless approach to use harsh or abrasive cleaning methods unless the job actually demands such.  I’ve actually seen a failure to adhere to this philosophy literally drive a few window cleaners out of business due to mere legal fees.

Hope this helps, #washon!