I’m sure that you’ve pondered for a long time what the exact science is to cleaning a glass window pane…who hasn’t, right?  Okay, I’m being facetious here, but really, there is a bit of science behind it. 

First off, let’s set the stage be saying, glass (common composition amorphous silicon dioxide) is an extremely dense and hard material. Yes, glass! It has a density of 2.58 grams per cubic centimeter (concrete is 2.24) and hardness of 5.5 on the Mohls Hardness Scale (diamond is hardest at 10). Furthermore, through various manufacturing techniques glass can also be incredibly strong.  To a window cleaner, it’s our bread and butter, and by having the fundamental knowledge about window glass density and hardness, we have become drastically better at cleaning it.  

In at least 95% of situations, when cleaning glass, you are rinsing/lifting the filth off the surface of the glass.  Airborne debris, dust, cobwebs, and other run of the mill nastiness, will stick to the glass pane, but due to its density and hardness, doesn’t actually go beyond its surface.  Therefore, the process of scrubbing the glass is meant to lift the filth off the surface and get it suspended in the water.  Once lifted, the process of squeegeeing or rinsing with a water-fed pole (WFP) then sweeps the filth off the surface.  This may seem trivial, but when you approach the cleaning in this sense, the end results are superior. 

What about the 5% of the situations where the above mentioned window cleaning techniques don’t cut the mustard?  The culprit is mineral deposits, otherwise known as hard water staining.  Mineral deposits are often caused by a rogue lawn sprinkler, water dripping from a roof or clogged gutter, or years of build-up and neglect. In these situations, the common cleaning process will not be effective. In these instances, a mild abrasive (less hard than the glass) and a glass buffing agent will need to be used to scrub the affected areas.  Once all mineral deposits have been buffed out, the normal cleaning process can then be followed.

By combining the science of cleaning glass and good ole’ fashion elbow grease, you too can enjoy the flawless views your home was meant to provide.