What To Do With Stinky Diapers

Offensive odors coming from your baby’s bumwear? There are a couple of reasons why this happens:

Hard water: Depending where you live, there may be an excess of calcium and magnesium mineral deposits in your water, making it “hard”. This means detergent doesn’t work as well, and minerals are actually being deposited back into the diapers, which can cause a less-than-fabulous smell.

Detergent alone can’t get rid of the minerals, so give it a boost by adding a separate water softener to your rinse cycle. I recommend Calgon Water Softener. It’s safe for use with our diapers.

To solve your hard water problem: ‘strip’ the diapers. This just means running a full hot wash cycle with no detergent, just Calgon. Repeat until the water is free of suds, then dry as usual. 

Bacteria build up / Detergent residue: If you know hard water isn’t your issue, then the culprit is probably detergent residue and/or bacteria in the diapers/inserts.

To solve your detergent problem: run your clean diapers through a few rounds of just-hot-water cycles, without any additional additives. Do this about 4-6 times.

To solve your bacterial buildup problem: the speedy solution is just to bleach the inserts (NOT the diapers themselves). Add 2 tablespoons of bleach to a hot wash cycle, and do an extra rinse at the end to wash out the bleach-y smell. Do this around once a month to keep your inserts fresh and odor-free!

Letting your inserts dry in the sun is also a great way to combat diaper smell. The sun is a natural disinfectant, stain remover, and whitener.

Urine Residue: As more and more people replace their washing machines with high efficiency front-loader models, we have seen more of this type of residue. 

How do you know if you have urine residue? Here are a few symptoms:
  • The smell of urine on diapers fresh out of the wash
  • Your baby has diaper rash (ammonia in the diaper can burn tender baby skin!)
  • They smell clean out of the laundry, but like ammonia after the first pee
To solve your urine residue problem: try doing several detergent-free hot water washes, then throw the diapers/inserts and wraps in the dryer. If rinses don’t work – you must increase the level of water used to wash and rinse your diapers.

To increase your washing water level: adjust your machine manually to the highest setting. If you can’t do that, call the manufacturer to get the how-to you need. Manufacturer can’t help you? Try the wet towel trick: decrease the number of diapers you wash per load, and add wet towels to your load in order to trick your machine into adding more water.

My diapers smell like ammonia after being worn. How do I fix that?

The chief culprits for that icky ammonia smell are scented detergent and detergent residue (you can find solution ideas for this above). Make sure you use an extra rinse cycle when washing your diapers, and double check that your detergent is perfume-free.

As you take diapers out of the washer, hold one to your face and take a big sniff. If it still doesn't smell clean, you need to use more detergent, a different detergent, or hotter water. If you decide to switch detergents, run your diapers through a few rounds of detergent-free hot water cycles first. This will ‘strip’ them, and make sure they’re clean and ready for use again.

My baby’s diapers smell fine out of the washer, but as soon as s/he wets them, they smell awful. Why?

The simple answer is that your detergent may not be rinsing out completely. If you have very hard water, try adding Calgon into your rinse cycle. If you change detergents, you may need to try stripping your diapers. Run a full hot wash cycle without detergent, repeating until the water is free of suds, then drying as usual.

Struggling with smelly microfiber inserts? It may be cheaper (and less work) in the long run to replace your inserts. Microfibers can start to lose their absorbency after a year of hot water washing and drying. For a small investment, you'll get an absorbency turbo boost, in addition to fresh-smelling diapers.

Remember though: while loss of absorbency can happen, it depends on your water and washing routine. Try bleaching your inserts first before you decide to replace them. Run a load with just the inserts and a small amount of bleach, and give the inserts an extra rinse to get rid of that chlorine smell.

Where does the smell come from?

When a wet cloth diaper smells very bad, it’s most likely due to an overproduction of ammonia.

Ammonia in the body is converted to urea, and excreted. Once the urine is released, the urea begins converting back to ammonia, causing the smell.

However, lingering urea in the diaper/insert, along with certain types of bacteria can speed up and increase the production of ammonia. So if you smell an unusually strong odor after your baby pees, there’s probably some biological residue hanging around.

Residue usually builds up when you don’t use enough detergent or hot water to wash and rinse your diapers clean. If there is too little of either, the urine is diluted, instead of being rinsed away. It’s recycled in the wash and dries onto the fabric, causing a stinky odor.