Can You Wash Cloth Diapers in Hard Water?

Can You Wash Cloth Diapers in Hard Water?

Our hot take: cloth diapering really can be as easy as 2 extra loads of laundry a week! An even hotter take? This is still possible, even if you have… dun dun dun… hard water!

Anyone who has spent any time online reading about cloth diaper wash routines has likely come across information on hard water. Some families think they flat out can’t cloth diaper because they have hard water! Other families think it’s going to be too complicated and throw in the towel before they’ve even begun. And then we have families who send themselves into a blind panic worrying about hard water when they don’t even have it. Rest assured, we’re here to help. 

Cloth diapering with hard water is like any other challenge we encounter as new parents - it is hard (pun intended 😉) until you have the right instructions and support – then it’s simple.

In this blog post we’ll be breaking down: 

  • What hard water is
  • How to know if you’ve got it
  • Options for treating hard water
  • How to wash cloth diapers in hard water (and how to “strip” cloth diapers if you’ve been washing them in hard water already)
  • And steps you can take to ensure hard water doesn’t wreak havoc on your cloth diapers

Let’s dive in!

What is Hard Water? 

Simply put, hard water is water that has a high mineral content (meaning lots of magnesium and calcium floating around in it). 

Is it dangerous? Nope! 

Is it a problem? Sort of. The high mineral content can be corrosive which can cause premature degradation of your pipes, appliances and laundered fabrics. What ends up happening is that households with untreated hard water will notice over time that their washing machine, dishwasher, bed sheets, t-shirts, etc don’t last quite as long as households with soft-normal water. (This article does an excellent job of explaining the effects that hard water can have on laundry)

How does Hard Water Affect Cloth Diapers? 

Washing in hard water presents 3 issues:

Holes in Fabric

Great question. As we mentioned above, washing in untreated hard water can cause premature degradation of your fabrics. This is especially true of diapers that get washed far more than any of your other household laundry. (diapers go through 2 wash cycles 2-3 times per week compared to maaaybe 1 wash cycle 1-2xs per week for your favorite set of pajamas)

Diapers Don’t Come Out Clean

But hard water does something else too. It impacts the cleaning performance of your detergent. How? Well, even the smartest detergents aren’t that smart. The surfactants and chelating agents in your detergent see those minerals that are floating around in your hard water and think they are “dirt” that’s meant to be cleaned. So instead of the detergent attacking the pee and poop in your cloth diapers, it gets distracted by the minerals and doesn’t do as effective of a job at cleaning your dirty cloth diapers as it would if the water were “softer”. In other words, the hard water minerals distract your detergent making it so it doesn’t do as good of a job. 

Build Up

And as if that weren’t bad enough, the minerals in your hard water also remain on the surface of your diapers after the final rinse and these lingering mineral molecules give the ammonia and bacteria in future pees and poops something to bind which then makes it even harder to wash your diapers clean in future washes. 


But is all hope lost? Definitely not. Keep reading. 

How do you know if you have hard water? 

If you think you’ve got hard water, there are usually some visual cues you’ll see around your home. Such as:

  • Chalky white residue spots on your faucets, showerheads, and appliances
  • Your glassware and dishes come out of the dishwasher with spots, streaks, or looking cloudy
  • Stiff laundry after it’s dry
  • Dry, crispy hair after showering

Odds are that if you don’t see any of these tell-tale signs in your home, you’re likely in the clear – but the best way to determine if you have hard water is to test for it.

Hard water is measured in PPM (parts per million) and it’s very easy run the test. You can pick up a hard water test kit at any hardware store, pet supply store or on Amazon.  Here’s an example of one.

You’ve tested, now what??

As if things aren’t confusing enough, you will likely find that different test kits have slightly different ranges telling you what ppm is considered soft, slightly hard, hard, etc. Don’t stress this too much. Instead, here’s our general rule of thumb.

0-75:  Your water is soft-normal. No concerns about hard water

75-120: Your water is hard. Some softening would be ideal but it’s not dire.

120 +:  Water softening is imperative to ensure your diapers are getting clean and  don’t degrade (holes, elastics wearing out, loss of water resistance on diaper covers, etc)

Households in the 0-75 and the 120+ range have it easy in the sense that the instructions are clear. It’s the ones that fall in that 75-120 range where things are a little murky. We’ve seen some families with 100 ppm that have no issues at all and others at 75 ppm with clear effects of hard water. This is because there are other factors at play too (such as the pH of your water and agitation power of your washing machine). 

If you fall in the 75-120 range and you are not modifying your routine and you are having great results, fantastic. Keep at it! If, however,  you are in that range and your diapers aren’t coming out of the washer smelling fresh and neutral and/or you’re noticing small holes or some fraying in your diaper fabrics, keep reading for treatment instructions.

How to treat Hard Water?

If you have hard water the most ideal way to mitigate it is to install a household water softener. This will not only protect your diapers but also your pipes, appliances and the rest of the laundry you wash. Having said that, a water softener is a bigger home modification and is not something everyone is able to do. That’s ok!

Another option is to simply add a water softener to each wash cycle (along with your detergent). The 2 softeners we have had the most success with are Borax and Calgon. 

We’ve found that Borax is great to a point (under 200 PPM). If your water is harder than that, Calgon is the better option.

It is very important to note that these water softeners ARE NOT a replacement for detergent. They are simply a companion to it. You will need to use both detergent AND the water softener in each wash cycle. 

How to Use Borax or Calgon when washing cloth diapers

The box of Borax does not give clear dispensing instructions 😖. Start with ¼ cup of Borax poured directly into the washer barrel every time you run a wash cycle. If that does the trick, great. If not, try increasing to ½ cup going up to ¾ if necessary. If ¾ is still not doing it, we recommend switching to Calgon.

Using Calgon is easy - you can simply follow the instructions on the packaging depending on how hard your water is. 

You have the tools, now how do you wash cloth diapers in hard water?

Ok so you have your dirty diapers, you’ve chosen a water softener, and a powerful detergent (like our Washing Powder – you can read all about why it’s the best detergent for washing cloth diapers here). Now here’s how use them!

We recommend washing “The Esembly Way” which we refined by running a busy NYC cloth diaper laundering service for over a decade! (when you’re washing over 15,000 diapers a week, like we were prior to launching Esembly, you’ve got a great opportunity to master the art of washing cloth diapers, which we certainly have! You can read all about how to wash “The Esembly Way” in this blog post!). Basic instructions are also included below for those that want to get right to it.


Esembly Cloth Diaper Laundering Instructions:

Every 2 - 3 days, load your washing machine ½ - ⅔ full with all of your cloth diapers, wipes, and accessories. (+ your 4 Agitator balls!)

Cycle 1

Run a “normal” cycle with warm water and 1 scoop of Washing Powder sprinkled on top (or measure for a “normal” load if using another detergent)

+ Borax or Calgon if needed for hard water

Cycle 2 

Run a “heavy duty” cycle with hot water* and 2 scoops of Washing Powder sprinkled on top (or measure for a “heavy duty” load if using another detergent)

+ Borax or Calgon if needed for hard water

*​Never use the Sanitary or Steam cycles of your machine - they simply get too hot for your diapers.

Anything else I need to be mindful of when washing cloth diapers in hard water?

Yes! Avoid any rinsing, spraying, or soaking of your diapers. We caution against this on our How It Works page since these practices on their own can lead to premature degradation of the cotton (along with other issues), but it's especially true when you have hard water. 

A good rule of thumb: if you’ve got hard water, you’ll want to limit your diaper’s exposure to the water as much as you can (so no extra rinses or anything like that either).

The Takeaway? 

Cloth diapering in hard water doesn't have to be a daunting challenge. With the right knowledge and a few simple steps, you can maintain clean and fresh cloth diapers for your little one. Remember that identifying hard water issues early on and addressing them promptly is key to ensuring the longevity of your cloth diapers. So, if you suspect hard water is affecting your laundry, don't hesitate to test it and choose the appropriate treatment.

Want to learn more?

Our co-founders host a free, virtual, Cloth Diapering 101 class every month to help cloth-curious parents get all the tools and information they need! You’ll learn:

  • How to use the Esembly diapers and accessories 
  • How to easily and effectively launder your Esembly diapers
  • The impact that your choice has on the planet, your wallet, and your day-to-day. 

You'll leave with the confidence to Live Less Disposably and a 20% discount code to use on your first order. 🥳 We hope to see you there!

Sign Up for Our Next Cloth 101 Class


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