What Are Hard Water Stains: Tips for Removing Water Stains from Windows

by Sep 24,2019

Are there hard water stains on your windows? If so, you might have noticed this common problem: No matter how rigorously you clean them, the windows still appear cloudy, with chalky white residue.

If you notice these tell-tale signs, chances are, there are hard water stains on home’s windows. These stains – which are also called limescale or hard water deposits – are caused by a buildup of the minerals commonly found in hard water. Unfortunately, hard water stains are difficult to remove, especially if you haven’t had your windows cleaned in over a year.

Think you might have hard water stains? Then, you might be wondering:

  • What causes hard water stains on windows?
  • Are hard water stains permanent?
  • And how can I remove them from my windows?

We cover all that in more in this short guide on hard water stain removal for windows.

What Causes Hard Water Stains?

In many Twin Cities communities, the water supply is “hard.” That means the water contains a higher-than-normal dissolved mineral content. In fact, many communities in the Twin Cities area have “extremely hard” water, according to Homewater101, which is due in part to the high mineral content of the region’s ground water.

After cleaning your windows with hard water, the water evaporates and the mineral deposits are left behind. The result is a cloudy, chalky look on the glass, white spots, or an almost moldy look.

Typically, these issues are caused when hard water reaches the windows, and some common ways that happens include:

  • Improper or irregular cleaning
  • Sprinklers spraying on your windows
  • Acid rain
  • Metal oxidation from aluminum frames
  • Using hard water for cleaning

Are Hard Water Stains Permanent?

If you’ve tried to clean hard water stains off your windows, you know they can be difficult to remove.

Here’s why: Those minerals – which are primarily calcium and magnesium – chemically react with the glass. Over time, corrosion occurs and the minerals begin to permeate the surface. That’s why it takes a lot of elbow grease to remove tougher, older stains.

Yet, if they’re left untreated long enough, hard water stains can cause window etching.

Etching occurs when the top layer of glass erodes. The minerals then start to create pits and small scratches on the surface, which often result in that milky, cloudy appearance. Removing the mineral deposits from etched glass is very difficult, and in the worst cases, may require the glass to be replaced.

How to Prevent Hard Water Spots on Your Windows

If you’re struggling to remove a stain, contact a window cleaning company. The best window washing companies have experience in hard water stain removal and etching restoration.

Ultimately, though, prevention is the best way to avoid etching on your windows. A few tips:

  • Regular Cleaning – Yearly or seasonal cleaning will remove hard water stains before they have a chance to “bake” in.
  • Use a Professional – The wrong tools and cleaning solutions can actually exacerbate this issue. For example, a caustic cleaner can harm the surface of the glass, making it easier for hard water stains to penetrate the surface. If you’re unsure of how to properly clean a window, contact a professional for best results.
  • Don’t Wait – As soon as you see water stains, have your windows cleaned. The longer you wait, the harder the stains are to remove.

Why Hard Water Stains Are Common in the Twin Cities?

Minnesota homeowners and businesses are in constant battle with hard water stains. Not just on windows, these stains can be found on cars, shower doors, facets, and glassware.

The reason? Minnesota – and in particular – the Twin Cities are known for having extremely hard water. In fact, throughout the Twin Cities, many communities have water hardness levels that are four times the national average.

That happens because the water in the region tends to have a high mineral content, but it also varies across the metro area depending on where the water is drawn from.

For example, communities that draw water from the Mississippi River, like Minneapolis and St. Paul have softer water. That’s because the river water isn’t as high in mineral content, and also because these larger cities have advanced water treatment facilities.

In the Minneapolis suburbs, though, particularly in the suburbs to the west, the water tends to be harder. That’s because these communities typically draw ground water from private wells. In Minnetonka, for example, water measures as having 18 grains per gallon (GPG) of mineral content, which is about four times the national average. Other areas like Maple Grove (25-28 GPG) and Brooklyn Park (32 GPG) have significantly higher water hardness ratings.

How to Remove Hard Water Stains

Hard water stains do require some special attention to remove. Therefore, a normal cleaning process that might include using water, detergent, a brush and squeegee won’t be effective. Instead, you’ll likely need to one or more of these methods:

  • Lightly Abrasive Cleaners – Glass is very delicate, and as such, overly abrasive cleaning supplies like a high-grit steel wool can damage the top layer. Lightly abrasive cleaners, though, can remove smaller stains that haven’t permeated the surface of the glass. This includes tools and solutions like: fine steel wool, scouring pads, baking soda and scouring powders.
  • Mild Acids – Natural acids like vinegar and lemon juice work well at loosening hard water deposits. Combining a natural acid with a lightly abrasive cleaner – like a scouring pad or baking soda – can also increase the effectiveness of these solutions.
  • Chemical Cleaners – The toughest stains may require more potent cleaning solutions. For example, specially formulated mineral deposit removers are designed to loosen tough mineral stains. Heavy staining might also require a more caustic solution like sulfuric acid to remove the tough deposits that have permeated the surface of the glass.
  • Glass Polish – If a hard water stain has caused etching, often a glass polishing compound is required to restore the surface, repair scratches and remove water stains.

Ultimately, using one or a combination of these supplies and solutions will greatly reduce the appearance of water spotting.

Are there hard water stains on your windows? Clean and Clear can help. We provide hard water stains removal for windows in the Minneapolis-St. Paul area. Contact us today for a quote or to learn more about how we can help.




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Tips for Removing Hard Water Stains from Windows | CleanandClearMN.com
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Tips for Removing Hard Water Stains from Windows | CleanandClearMN.com
What Are Hard Water Stains. Check out these tips by CleanandClearMN.com for removing hard water stains from your windows.
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