Before We Start: Diagnosis

A leaking diaper can be caused by multiple things. Let’s figure out which one you’re dealing with:

The Leak Test

Put the diaper on your kid (or don’t, if you want to test it first):

  1. Water beads up on the surface = Repelling issue
  2. Diaper is soaked but leaks out the legs = Fit issue or worn elastic
  3. Diaper is completely saturated = Absorbency issue
  4. Leaks from a specific spot = Possible PUL delamination

Now let’s fix each one.

Problem 1: Repelling (Most Common)

What’s Happening

The diaper’s inner layer is repelling moisture instead of absorbing it. This is usually caused by:

  • Detergent buildup
  • Fabric softener residue
  • Diaper cream residue
  • Hard water mineral deposits

The Fix: Strip and Sanitize

Step 1: The Prep

  • Remove the insert from the pocket
  • Check that there’s nothing stuck to the fabric (old diaper cream, etc.)

Step 2: The Strip

  • Fill your sink or bathtub with hot water (hottest your tap produces)
  • Add 1-2 drops of blue Dawn dish soap (yes, it has to be Dawn, yes, it has to be blue)
  • Submerge the diaper and insert
  • Agitate it around for 2-3 minutes
  • Let it soak for 15-20 minutes
  • Rinse thoroughly - and I mean THOROUGHLY - until no soap remains

Step 3: The Sanitize

  • Run the diaper through a hot wash cycle with NO detergent
  • Add 1 cup of white vinegar to the rinse cycle
  • Run an extra rinse if your machine has that option

Step 4: The Test

  • Drip some water on the inner layer
  • It should absorb immediately
  • If it still beads up, repeat the process

Why This Works

Dawn breaks down the oils and residue causing the repelling. The hot wash and vinegar remove any remaining buildup. Your diaper is now reset to factory settings.

Problem 2: Fit Issues

What’s Happening

The diaper doesn’t fit properly, so pee leaks out the legs or waist before the diaper is saturated.

The Fix: Adjust or Replace Elastics

Step 1: Check the Elastics

  • Lay the diaper flat
  • Stretch the leg elastics
  • They should snap back quickly and firmly
  • If they’re loose, stretched out, or don’t snap back, they need replacing

Step 2: Temporary Fix (If You’re Not Ready to Sew)

  • Try adjusting the rise snaps - sometimes going up or down one snap helps
  • Make sure the elastic is sitting in the leg crease, not on the thigh
  • Try a different insert that fits better (thicker or thinner)

Step 3: Permanent Fix (Replace the Elastic)

This requires basic sewing skills:

  1. Use a seam ripper to carefully remove the old elastic
  2. Measure the new elastic (it should be about 1-2 inches shorter than the leg opening when laid flat)
  3. Pin the new elastic in place, stretching slightly as you sew
  4. Use a zigzag stitch to secure it
  5. Test the stretch - it should be snug but not cutting off circulation

Real talk: If sewing isn’t your thing, you can:

  • Send it to a diaper repair service (they exist!)
  • Accept that this is now your “around the house only” diaper
  • Retire it and use it for burp cloths or cleaning rags

Problem 3: Not Enough Absorbency

What’s Happening

Your kid is outpeeing the diaper. This is common as they get older or if they’re a heavy wetter.

The Fix: Add More Absorption

Option 1: Add Layers

  • Double up inserts
  • Add a hemp booster between the insert and diaper
  • Use a more absorbent insert (hemp or bamboo instead of microfiber)

Option 2: Change More Frequently

  • If you’re changing every 3 hours, try every 2 hours
  • Check if your kid is drinking more water (growth spurts = more pee)
  • Consider if they’re ready for overnight diapers with extra absorbency

Option 3: Strategic Boosting For boys: Add extra absorbency in the front For girls: Add extra in the middle/bottom For stomach sleepers: Add extra in the front For back sleepers: Add extra in the back

Why This Works

More absorbent material = more pee contained. It’s not rocket science, but it works.

Problem 4: PUL Delamination

What’s Happening

The waterproof PUL layer is separating from the fabric, creating spots where water can leak through.

The Fix: Patch or Replace

Step 1: Identify the Problem Area

  • Hold the diaper up to a light
  • Look for spots where the PUL looks separated or milky
  • Feel for areas where the layers feel loose or crunchy

Step 2: Small Spots (Temporary Fix)

  • You can try sealing small spots with PUL fabric glue
  • This is temporary - maybe 10-20 more washes

Step 3: Large Areas (Permanent Fix)

  • You’ll need to replace the PUL
  • This requires sewing skills and PUL fabric
  • Honestly? This is usually when we retire the diaper
  • It’s had a good life

Real Talk: If the PUL is failing, the diaper is probably at the end of its life. You can try to patch it, but it’s likely time to replace it or repurpose it.

The Comprehensive Troubleshooting Checklist

If you’ve tried everything and it’s still leaking, work through this:

  • Did you strip and sanitize?
  • Are the elastics tight?
  • Is the insert actually absorbent? (pour water on it - it should soak in immediately)
  • Is the insert pushed all the way to the front of the pocket?
  • Are you using diaper cream? (If yes, are you using a liner?)
  • Is the diaper actually the right size for your kid?
  • Have you checked for PUL damage?
  • Is the insert coming out of the pocket during wear? (tucking issue)
  • Are you waiting too long between changes?

When to Give Up

Sometimes, a diaper is just done. Here’s when to retire it:

  • PUL is significantly delaminated
  • Elastics are shot and you don’t want to replace them
  • The fabric is so thin you can see through it
  • You’ve stripped it 3+ times and it still repels
  • You’ve tried everything on this list twice

It’s okay to retire diapers. They’ve served their purpose.

The Success Rate

In my experience:

  • 70% of leaks = Repelling (fixed with stripping)
  • 20% of leaks = Fit issues (fixed with elastic replacement or different insert)
  • 5% of leaks = Not enough absorbency (fixed with boosters)
  • 5% of leaks = Dead diaper (time to retire)

So chances are, your diaper is salvageable.

Prevention Tips

To avoid leaks in the future:

  1. Strip your diapers every 3-4 months (preventative maintenance)
  2. Check elastics regularly and replace before they’re completely shot
  3. Use enough detergent but not too much (follow the package directions)
  4. Don’t use fabric softener (I know I said this already, but seriously)
  5. Use a liner if you’re using diaper cream
  6. Change frequently enough for your child’s output

The Bottom Line

Most leaking diapers can be fixed. It usually takes less than 30 minutes and costs nothing.

Before you throw that diaper out or declare that “cloth doesn’t work,” try these fixes.

You might be surprised.

And if it still doesn’t work after all this? Then yes, that diaper is done. But at least you tried everything.


A Note on Warranty: Some diaper brands have warranties. If your diaper is relatively new and the PUL is failing, contact the manufacturer before trying to fix it yourself. You might get a replacement.

Another Note: If ALL your diapers are leaking, the problem is probably your wash routine, not the individual diapers. That’s a whole separate issue (and a whole separate post).

Have questions? Leave a comment. Have a leak I didn’t cover? Tell me about it. Have a fix that worked better? Share it. We’re all figuring this out together.