Tuesday, October 2, 2012

The Science Behind Detergent

Whether you have just decided to cloth diaper, or have been using cloth for years, there will come a time when your detergent fails. It could be a detergent that you have been using for weeks or months, or it could be a brand new detergent that you just tried for the first time. My diapers stink, my diapers leak, my child has a rash! These are common posts, found on blogs, boards, and written in emails. The first person to blame is usually the detergent itself ex: Detergent XYZ gave my child a rash, or detergent XYZ caused my diapers to leak! Regardless of the problem, the detergent company is usually the first to blame. But before you blame the detergent itself, it is important to understand the "science" behind detergent and how it works. Sometimes all it takes is some adjustments to your wash routine to get the clean diapers you are looking for!

Water is key!

The single most important ingredient when washing diapers is WATER. After all, it makes up 99% of what you are washing your diapers with.  The quality of your water is critical. It is recommended that if you have even moderately hard water that you invest in a water softening device. This will save you time and money in the long run and even elongate the life of your clothing. Having a water softener also helps with the wear and tear on your washing machine and plumbing as well. Your water hardness is measured by the level of calcium and magnesium carbonate present in your water.  Other things that will affect your water's washing ability is chlorine, iron, alkalinity, total dissolved solids etc. The ingredients in detergent react differently to the minerals in your water. This is usually not noticed when washing clothing, but we are talking about cloth diapers here, which is entirely different. Clothing is not (or should not be) peed and pooped in on a daily basis.


Your water contains minerals. Hard water minerals need to get broken down in your wash cycle. That is what a water softener or an added softener like Calgon does. They break down the minerals. Otherwise, these minerals will bind with the active ingredient in the detergent making it less effective. The minerals then can also re-deposit back on to your diapers essentially clogging the fibers and preventing your diapers from getting clean. This can lead to that barnyard, not-so-clean smell, ammonia build up, and rashes. Some detergents will add ingredients specifically to combat this problem. Examples would be: Sodium Carbonate, Sodium Borate, or other surfactants that do not bind with the ions in your water. Sometimes those with extremely hard water may still need to add a water softener even when using detergents specifically formulated for hard water.

There are 4 main factors:  

Chemical Action, Water Temperature, Mechanical Action, and Time.  All 4 factors must be present to wash cloth diapers effectively.

1. Water Temperature: Washing in warm to hot water is always best. For every 10 degrees your water drops in temperature, there is a 50% reduction in the chemical reaction. Also, temperature must reach 140 degrees to kill the bacteria in your diapers. Most detergents work better/faster in warmer temperatures.

2. Chemical Action: The detergent added to your machine. People are so afraid of using too much detergent, that they tend to use too little instead. Using too little detergent, or detergent that is getting diluted by too much water will result in stinky diapers. I have yet to find a detergent that will really work with only 1 TBSP for the long run. 

3. Mechanical Action: This is achieved by the diapers rubbing up against each other in your wash cycle. Proper friction is needed for the fibers of your diapers to get clean. Imagine washing your hands: if you just put soap on them an ran them under water - your hands would not get very clean. You need to rub them to together. The same is true for fabric. That is why it is also important to have the right load size. Too many diapers and they move around your washing machine in one clump. Too few diapers and they swim around the water in your machine unaware of each other. 

4. Length of Cycle: This is a very important factor in washing cloth diapers. If the diapers are not exposed to the Chemical Action and Mechanical Action (detergent & friction) long enough, the fibers are not penetrated by the water and soils are not released. A 15-20 minute wash cycle is usually not going to be very effective. If that is the longest setting your machine offers, consider two wash cycles in a row. 

 If you decrease one of the 4 main factors, then you need to increase the other three! So if you are washing in a lower temperature, you need to increase your other factors.

Fabric Types:

Believe it or not, the type of fabric you are washing does make a difference! 

Cotton: If a diaper is made of 100% cotton (like a pre-fold) it is going to be the easiest to clean. Why? Because it is made of layers of cotton twisted around itself and is very absorbent, which means it loves wetness! This makes cotton diapers easy to rinse clean without build-up. 

Polyester is derived from oil so it initially will repel water. It takes a little more time to wash and likes to hold on to oily stains. If not properly washed can lead to stink.

Microfiber: In reality, there is no such "fabric". Microfiber is a man-made fiber that is made up of channels. These channels pull moisture deep inside, which makes it very absorbent. This also makes them very difficult to clean. The detergent and water must fully penetrate into these channels to get them clean which is hard to do, because the channels are already filled with urine. That is why people tend to have more stink issues with microfiber.

Water Level: 

Water level is also very important when washing cloth diapers. A common misconception is that you need lots and lots of water to wash cloth diapers. That is not entirely true. A lot of water is necessary for pre-rinsing your diapers and flushing out the urine. It is also good to have a lot of water for your final rinse cycle. However, a mistake that is being made over and over is too much water and too little detergent. You have to pick a side here. If you are washing a small load of diapers, but are setting your machine to L or XL load and then using 1-2 TBSP of detergent...chances are your detergent is getting too diluted to clean your diapers effectively. If your water level is too high, your diapers are also probably missing the friction needed to get clean. Instead they are swimming around in gallons of extra water. Try reducing the amount of water in your wash cycle so that your diapers are fully saturated with some extra water. If possible, set the water on high for your pre-rinse cycle or at the end for your extra rinse instead. 

Okay, now what?

Now that you know the science behind detergent, but your diapers stink or your child has a rash what do you do?  Contact the manufacturer of the detergent you are using. Don't rely on posts made by others, blogs, and reviews. Sure, you can read them to get ideas and see if others have gone through what you have and you can pick up on something you haven't tried before. But the true experts are the manufactures! They know exactly what is in their detergent and what routines work best based on your machine, water type, water level etc. The manufacturers of cloth diaper detergents are eager to help and are owned by small families and their products are used on their own children. More than likely you will need to adjust your wash routine and yes - even sometimes switch your detergent if all else fails.

Wash Routine:

I get washing questions and emails all the time. I have done tons of research, and spoken to my detergent manufactures at length. I do find that most often users having problems are using too much water, too little detergent, or they have a short wash cycle.  Another common problem is too many washes & rinses without detergent when you have hard water. If the minerals are not broken down properly, they will re-deposit back on to your diapers and cause stink, build-up, and rash. It is very rare that the detergent is "causing your child's rash", more than likely it is the way the active ingredients are reacting with the minerals in your water in conjunction with how you are washing your diapers (ie: wash routine).  I have found the following suggestions work really well:

  1. Ditch the pre-rinse. Instead run a short wash or pre-wash cycle with warm water if possible. If you are battling stink, try adding 1 TBSP of detergent to this cycle.
  2. Make sure you are using the longest wash cycle your machine allows. If your cycle is under 20 minutes you may want to consider a pre-rinse in cold, followed by two hot water washes with detergent instead.
  3. If you have a top-loader, before your main wash - pull the knob out and let your diapers soak in the hot water with detergent for 1/2 hour. Push the knob in and let the cycle complete.


Not every diaper works for every child. While you may be in love with Fuzzi Bunz, your sister may think they are terrible and leak. The same thing goes for detergents. Your water, mineral content, washing machine, water level, types of fibers, and cycle length all factor in when finding the detergent is right for you. If a detergent is not working for you, contact the manufacturer & try the suggestions they give you. If it still does not work, switch detergents. But please remember that these family owned companies care about creating the best possible product for you and your babies. I have tried several detergents. Some of them worked okay, and some of them did not. Maybe I didn't give it enough time, maybe my routine was off, maybe the detergent reacted with the minerals in my well water.  Now that I have found the right detergent for me, I have not had to strip my diapers, and I no longer struggle with ammonia or rashes.I still play around with my routine, even after 3 years of cloth diapering, and I find that switching up my routine every now and then, washing them a few extra times, doing a mini-soak ect. works wonders!  If one detergent worked for everyone there wouldn't be an entire grocery store aisle full of different detergent brands to choose from, there wouldn't be a million types of soaps, toothpaste, jeans and the list goes on! 

Enter to win a $15 gift card to Cutie Poops and Bottoms so you can buy some detergent! (or anything else you want)

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  1. Thanks so much for a great post. I completely agree with you. I had been struggling so much and switching detergents over and over. When I was just about to give up I gave Eco Sprout a try. I was still having problems, but with a few emails back and forth we figured out the problem. My wash cycle was too short and I was using too much water! I ♥ Eco Sprout and am grateful for their great customer service, I will never use anything else on my diapers!
    Michelle, cdemomtoJ&E

  2. What a timely post! I was just emailing you about my stink problems... I tried a few things and we're doing better now :-)

  3. Thanks this had alot of good information

  4. A lot of great information here! Thanks so much!

  5. Great info! I really learned a lot about washing my diapers. Thank you :)

  6. It's nice to have all this information in one place. I think I'll send a link to my sister-in-law who is borrowing some of my diapers to use with her newborn.

  7. Very helpful. Has anyone noticed more ammonia smell when you started solids?

  8. so much good info in here! thanks! and i've never considered that i'm using TOO much water!! but it does make sense....if we have stink issues again, I might see if that's what's causing them...

  9. Lots of good info!

  10. I agree with you on the switching it up every once in a while. I enjoy trying new detergents and tweeking my wash routine every now and then to see if I can find something that works better!

  11. This was a great article to read. I consider myself a cloth diapering 'pro' and love to read about washing routines. It is wise to switch things up, and to strip diapers on occasion! Thanks for all the helpful tips!

  12. Great info! I will have to pass it on to my new cloth diapering friends :) I wish I had read this before/ right when I started cloth!

  13. Thanks for the post. This is a definite must read!

  14. Thanks for the giveaway : ) Great article!

  15. thx for the info!! i yhave been having some issues lately so thius is great timing!

  16. So interesting to read about wash options and how others do it!


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