Cloth Diaper Fabrics Explained: Choosing the Right Materials for Your Baby

Now that you understand the different types of cloth diapers, the next step is understanding what they’re made of.

Fabric plays a major role in how a cloth diaper performs. It affects:

• How quickly moisture is absorbed

• How much liquid the diaper can hold

• How breathable it feels

• How it performs overnight

• How it interacts with your baby’s skin

This post is part of our Cloth Diapering for Beginners series, where we break everything down clearly so you can build a diapering system that works for your baby and your routine.

Natural vs. Synthetic Cloth Diaper Fabrics

Cloth diaper fabrics generally fall into two categories:

• Natural fibers

• Synthetic fibers

Many families use a combination of both. The key is understanding how each performs.

Natural Fiber Cloth Diapers

Natural fibers come from plant-based materials and are often chosen for breathability and skin-friendliness.

Organic Cotton

Organic cotton is one of the most trusted materials in cloth diapering.

Why families choose organic cotton

• Soft and breathable

• Gentle on sensitive skin

• Durable and long-lasting

• Absorbs well without compression leaks

• Easy to wash and maintain

Cotton offers reliable performance and simplicity. Many families appreciate knowing exactly what is touching their baby’s skin, especially during the newborn stage.

Hemp: Raw Fiber vs. Hemp Viscose

Hemp is widely known for durability and absorbency — but not all hemp fabrics are the same.

Raw Hemp Fiber

Raw hemp fiber:

• Has a slightly rough texture

• Often contains visible slubs

• Has a natural beige tone

• Is extremely durable

Because raw hemp can feel coarse, it is almost always blended with cotton when used in textiles to soften it and improve comfort.

Hemp Viscose (Rayon from Hemp)

Much of the “hemp” used in cloth diapers today is actually hemp viscose, which is processed similarly to bamboo viscose.

Hemp viscose:

• Is smooth and bright white

• Has a uniform texture

• Performs similarly to bamboo viscose

• Lacks the textured appearance of raw hemp

If a hemp insert is smooth, soft, and bright white, it is likely viscose. If it has texture, visible slubs, and a natural tone, it is more likely raw hemp blended with cotton.

Bamboo Viscose (Rayon from Bamboo)

Bamboo viscose is a semi-synthetic fiber derived from bamboo pulp and processed into rayon.

At Smart Bottoms, we use either cotton or bamboo in our diapers. We chose bamboo specifically because of how it performs.

Why we (and many families) choose bamboo

• Extremely soft against baby’s skin

• Highly absorbent

• Absorbs faster than many hemp/cotton blends

• Approximately 30% more absorbent than cotton alone

• Smooth, flexible, and comfortable

In our testing and long-term use, bamboo viscose consistently outperformed hemp/cotton viscose blends in both absorbency speed and total capacity. That means it can hold more moisture and absorb it more quickly — two factors that directly impact leak prevention.

Bamboo offers an excellent balance between comfort and performance, making it a strong choice for everyday use and overnight boosting.

Synthetic Fabrics in Cloth Diapers

Synthetic materials are often used for either absorbent inserts or inner stay-dry linings.

Microfiber Inserts

Microfiber is a synthetic material made from extremely fine polyester fibers.

Why microfiber absorbs quickly

Microfiber has a large surface area, allowing it to absorb liquid rapidly.

Why microfiber should not touch baby’s skin

Microfiber should never be placed directly against baby’s skin because:

• It pulls moisture aggressively

• It can overdry skin

• It may cause redness or irritation

• It can contribute to rashes in sensitive babies

For this reason, microfiber inserts must always be placed inside a pocket diaper behind a liner.

Other considerations

• Prone to compression leaks

• Breaks down faster over time

• Often included in lower-cost diaper systems

Stay-Dry Lining Fabrics

Many cloth diapers include a synthetic lining designed to create a stay-dry feel. These fabrics sit against baby’s skin and allow moisture to move into the absorbent core.

The most common stay-dry fabrics are:

• Microfleece

• Microsuede

• Athletic wicking jersey (AWJ)

Microfleece

Microfleece is a soft polyester fabric commonly used inside pocket diapers.

How microfleece works

Microfleece does not absorb liquid. Instead, it allows moisture to pass through to the absorbent layer underneath when pressure is applied (such as when baby is sitting or lying down).

Important fit consideration

Because liquid transfer depends on pressure:

• If the diaper is too loose, moisture may not pass through properly

• Liquid can bead or roll across the surface

• This may lead to leaks at the legs or waist

Proper fit is especially important with microfleece-lined diapers.

Microsuede

Microsuede is another polyester-based stay-dry lining.

How microsuede works

Like microfleece, microsuede:

• Does not absorb moisture

• Requires pressure to push liquid through

• Creates a stay-dry feel once moisture transfers

Important fit consideration

If the diaper is too loose:

• Moisture may not transfer effectively

• Liquid may roll along the surface

• Leaks are more likely

Microsuede tends to have a smoother appearance and may resist pilling more than microfleece.

Athletic Wicking Jersey (AWJ)

Athletic wicking jersey (AWJ) is a synthetic performance fabric used in some modern cloth diapers.

How AWJ works

AWJ is designed to actively wick moisture through the fabric and into the absorbent core underneath. Unlike microfleece and microsuede, it does not rely primarily on pressure to move liquid.

This means:

• Liquid transfers more consistently

• Fit still matters, but pressure is not required for absorption

• Moisture is pulled away from baby’s skin efficiently

Things to consider

• Synthetic material

• Creates a stay-dry feel

• Less breathable than natural fibers

• May not be ideal for babies sensitive to polyester

Some families prefer AWJ for its performance, while others prefer natural fibers directly against baby’s skin.

Waterproof Layers: TPU (Often Labeled as PUL) & Wool

The outer layer of a cloth diaper is typically made from laminated fabric.

You’ll often see this referred to as PUL (Polyurethane Laminate). However, most modern diapers today actually use TPU (Thermoplastic Polyurethane).

Both materials bond a waterproof polyurethane layer to fabric.

• PUL traditionally refers to chemical lamination

• TPU uses a heat-bonding process

In everyday use, they perform very similarly in:

• Waterproofing

• Flexibility

• Durability

• Washability

Most modern diapers use TPU, though many still label it as PUL because the term is more widely recognized.

Wool Covers

Wool is a natural waterproofing alternative.

Unlike TPU, wool:

• Absorbs some moisture

• Allows airflow

• Naturally resists bacteria and odor

Why families choose wool

• Extremely breathable

• Fully natural fiber

• Excellent for overnight

• Can be worn multiple times between washes (if not soiled)

Wool requires lanolizing and special care but is valued by families seeking a fully natural system.

Quick Summary: Cloth Diaper Fabrics

• Cotton is breathable and reliable

• Raw hemp is durable and textured

• Hemp viscose and bamboo viscose are smooth and highly absorbent

• Bamboo absorbs faster and holds more than cotton alone

• Microfiber absorbs quickly but must not touch skin

• Microfleece and microsuede require pressure for liquid transfer

• AWJ actively wicks moisture without relying on pressure

• Most diapers use TPU (often labeled as PUL)

• Wool is a breathable natural cover option