As a cloth diaper parent, it doesn’t take long before you hear the word “wicking” being thrown around in Facebook groups, product reviews, and blog posts.
So what is cloth diaper wicking, exactly? Scientifically, wicking is a principle of capillary action that involves absorbing or drawing off liquid; for diaper users, wicking simply means the transfer of moisture from one area to another, which can be a good thing or a bad thing.
The Negative Side Of Cloth Diaper Wicking
Have you ever put your baby into a diaper and left the tiniest corner of fabric sticking out of the waist of the diaper cover, or had the faintest edge of a prefold sticking out of a leg gusset? Or, conversely, perhaps a teeny bit of baby’s pajamas bunched up and touched the inside of her diaper when you laid them down to sleep? If this has ever happened to you, you’ll know the frustration of picking up a crying, cold, and clammy baby lying in urine-soaked clothes or bedsheets.
At the time, you may have chalked this up to the diaper leaking, but chances are, if the diaper is new and well-constructed, it was wicking (or moisture transfer) that created the wetness problem, not actually a hole or flaw in a leaky diaper cover.
With this negative type of wicking, moisture moves along a thirsty bit of fabric (like cotton inserts or jammies) and is literally sucked down the fibres of the cloth and into the surrounding textiles. This moisture transfer can really be amazing in its efficiency, not only creating a minor damp spot where the threads touched one another, but truly creating a channel for moisture to continuously flow and escape.
How to Prevent Bad Cloth Diaper Wicking
Obviously, no one likes this type of wicking! So how can you prevent it?
To prevent negative diaper wicking, ensure that all diaper fabrics are well-contained within a waterproof diaper cover consisting of some non-wicking fabrics, like PUL (polyurethane laminate), wool, or even old-fashioned “plastic pants.”
Don’t allow even the tiniest corner of the fabric to stick in or out of the diaper area, Remember that hidden within textiles is the perfect escape route for liquids to travel along–a fibrous highway of sorts.
Occasionally, some diapers themselves are constructed in a way that can contribute to negative wicking. Watch out for diapers or covers that provide some sort of connection between the inside and the outside of the cover–even the tiniest connection (such as a rolled edge, or threads stitched through all the diaper layers on a band of velcro). This can be enough to enable the transfer of urine from the inside layer of the diaper to its outside environment.
Another problem area can be cotton-trimmed edges or elastics that have a solid band of fabric that travels from the inside of the diaper to the outside. Oftentimes, although these diapers may have a very cute “two-tone” look, moms find them frustrating to use when they seem to “leak” out onto baby clothes and bedding time and time again.
So, overall, the key to preventing leak-like diaper wicking is to ensure that anything you intend to hold urine is totally isolated within the diaper’s waterproof (or water-resistant) layers with no bridge of textiles–even a few threads–leaving a route to the outside environment.
The Positive Side of Cloth Diaper Wicking
Wicking, or moisture transfer, can also be a positive thing when talking about cloth diapers.
Obviously, for both comfort and rash prevention, it is optimal to reduce the amount of time that baby spends sitting in a moist diaper. While you should be changing our babies as soon as they wet during the day to prevent yeast growth and diaper rash, life happens, and catching a wet diaper right away isn’t always possible.
Luckily the science of moisture transfer can help us out in keeping babies comfy and dry in between diaper changes.
While “natural fibers” such as cotton, hemp, and bamboo are incredibly thirsty and absorbent, once saturated, they stay very saturated, even next to your baby’s sensitive skin. While they may continue to absorb and absorb and absorb (until they can simply hold no more), they will feel wet, cold, and uncomfortable on a baby’s skin as they do so.
Because of this, pocket diaper manufacturers and some all-in-one diaper makers use wicking fabrics as the lining for diapers in order to facilitate the movement of moisture away from a baby’s skin and into the deeper layers of cloth.
Traditionally, microfleece and microsuede were used as the “stay dry” layer next to the baby’s skin. More recently AWJ (Athletic Wicking Jersey) has become a trendy choice since it provides a cooler stay-dry surface than the warmer fleece and microsuede. AWJ is also made from synthetic fibres such as polyester, bamboo rayon, or nylon.
All these synthetic fabrics have been specifically designed with wicking capabilities, able to drink in moisture and quickly move it straight through the top layer of fabric and into a more absorbent fabric (like a cotton pad) placed underneath (away from baby’s delicate skin).
Synthetic fabrics designed specifically to wick have next to no absorbancy–they exist only to facilitate the transfer of liquids and to stay dry even when continuously drenched with liquid.
How to Use Cloth Diaper Wicking to Your Advantage
In short, if you aren’t using diapers that have a stay-dry layer on top, you can still create your own positive stay-dry wicking system by making some DIY, no-sew microfleece liners (instructions here).
Of course, don’t forget to contain your diaper liner, as well as the absorbent layers of your diaper, within a waterproof cover or shell to prevent the negative kind of wicking (leaking) from spreading to your baby’s clothes, blankets, or bedding.
With wicking on your side, here’s hoping both you and baby will enjoy many dry nights and deep slumbers!
If you do experience diaper leaks, and aren’t sure where they’re coming from, you can read more about all the causes of cloth diaper leaks and how to fix them here.