The 1,2,3’s of Hard Water Stain Removal
“How can I get the hard water stain off the window?” This is consistently one of the most popular questions from professional window cleaning contractors. Whether the stain is from sprinkler overspray or building run off, the stain needs to go away and get off the glass. Period.
There is a lot to this topic. The variety of stains list is endless. Over the years, pro window cleaners have shared many of their field experiences with our team at Detroit Sponge. In this article, hard water stains are the topic. There are many other types of stains on glass. Sealant residue, paint, tar, silicon, and even grease are examples of other residues window cleaners encounter on the glass. Those are for discussion another day. For today, the concern is a stain or deposit that is left on windows by minerals. These minerals often are from sprinkler systems or runoff from building surfaces.
WORD OF CAUTION – If the glass has reflective coating installed on the surface of the glass, hard water stain removal will not be a good choice. Most of the time, there is little that can be done in this situation.
SECOND WORD OF CAUTION – NOT ALL STAINS CAN BE SUCCESFULLY REMOVED! If left unattended and neglected for years of exposure to the outdoor elements, stains can become permanent.
But let’s take a look at how to maximize the chance of success in removing mineral deposits from windows.
To think about removing a mineral stain from a window, consider these 3 basic steps:
- Asses
- Test
- Get to work
ASSES
The removal process should start with the first step of diagnosing the type of glass and the stain. There are many types of glass on the market. Not all surfaces can be treated with abrasives or chemicals. In the case where the glass has a reflective coating on the exterior surface or is made of one of the newer, advanced technology surfaces, you will want to research the type of glass to be sure that stain removal is an option. An easy example would be a glass that has a coating preventing anything abrasive from being used.
While sometimes it is impossible, take a look around the glass with the stain and try to figure out what might have caused the issue. Often, it will be an obvious source. A simple example would be a poorly adjusted sprinkler head. Knowing the likely source helps with two things:
- Allows you to have an explanation conversation with the customer
- Might provide a clue as to what chemical or product will be most effective
The first point can’t be emphasized enough. The stain was not caused by you. The issue is the customer’s and you are going to do your best to solve it. Not identifying and discussing can create very difficult future discussions! Additionally, if you do not alert the owner to the probable cause, even if effective in removing the stain, the stain will come back. In our example of a poorly aimed sprinkler head, the stain will continue to be created unless the sprinkler is adjusted.
To continue with our example of a sprinkler causing the issue, if there is a known problem with a particular mineral, let’s say iron, then you can direct your choice of treatment to match that type of stain.
Once you have assessed the stain, it is time to test options for removal.
TEST
Most professional window cleaners use a process of testing different techniques and chemicals to do the removal. Options range from aggressive, acid-based cleaners down to the most popular, abrasive-based cleaners that are not chemically aggressive at all. The important part is to TEST a small area before attacking the entire glass surface. This is true regardless of which product you select to use. Testing a small, inconspicuous space is ALWAYS the right first step.
In most cases, the most popular removal products we sell will work on the widest variety of stains. These most popular products might require more elbow grease and abrasion, but these chemicals are not “aggressive”, making them safe options to use around frames, etc..
These products would be choices like BioClean, Diamond Magic, Unger RubOut, Ettore Scrub Off, and A-1 Stain remover. Provided in a paste consistency, these products each offer varying types of “grittiness.” Some are more gritty than others, but each would be intended to use with agitation of a scrubber or scrub pad. The idea is that the products will help to rub the stain off of the window.
If these first types of products do not provide good results in your test area, there are other, chemically stronger solutions for your consideration. In our line up, we have the Crystal Clear 550 and the OneRestore. Both of these products are liquid based and rely on more aggressive chemicals to digest the stain off of the glass. Depending on the severity of the stain, these products can be diluted. The mixture would all depend on the effectiveness of the product on the stain. It is really important that the label of these products be read and all instructions provide to be followed. One warning for sure is to never let either of these products dry on the glass. That does not lead to anything helpful. The Crystal Clear 550 and the OneRestore are truly contractor strength products and should be used with attention and care.
Once you have assessed the stain and then tested the glass for success, it will be time to get to work!
GET TO WORK
This is the step that most people want to go right to. Grab the product and hit the glass, right? Do yourself a favor and complete steps 1 and 2 before going to work on a wide scale on the glass. You will need different supplies depending on the product that you find effective. Make sure you have assessed, tested and then prepared to begin working.
- Follow the manufacturer directions on the bottle and work small areas at a time.
- It is common for the stain to remove partially. Simply wash and reapply. Stains can be built up and will often be released in layers.
- Speed is not the biggest goal! Success is the goal.
There are few stains that can ruin a view like a hard water stain. Most of the time, mineral spots can be successfully removed from the window surface. These steps are a great way to have a process that works for removing these stains from the windows successfully. Assess, test and get to work!