In the first CD 101 post, I mentioned some aspects of fabrics, like PUL covers. The Lookie What I Made! post also discusses wool diaper covers. There are a number of choices when it comes to cloth diaper fabrics and materials. I'll share what I've learned, but this is no way comprehensive.
Cotton. This is the fabric of choice for prefolds, flats, and some fitteds. Very absorbent, so it holds alot of moisture. But it doesn't "wick" or move the moisture like some fabrics do, so the moisture stays right up against the skin. Most mamas change cloth diapers frequently, so this is not a problem for them.
Most cotton for prefolds is not organic, unless it is specified. And then you'll know, because the diapers will be quite a bit more expensive. But if you're determined to use all organic fabrics for your little one, you can find organic cotton prefolds.
"Sherpa" and "velour" (unless it is specified as bamboo velour) are types of cotton fabrics. Sherpa is textured like a thick cotton towel, and is a great fabric for fitteds. Kissaluvs fitteds are cotton sherpa, and lots of mamas swear by this fabric to "catch" the runny poo of breastfed newborns. Velour is very soft and is often used as the top layer next to baby's skin since it is so soft.
(A KLo - Kissaluvs size 0 fitted diaper - made of sherpa)
Bamboo. Another very popular fabric for cloth diapers is bamboo. There is much discussion over these fabrics, as research into the method of turning bamboo into fiber reveals that it is not as "natural" or "green" a process as most folks would believe. Some mamas now refer to the fabric as "rayon from bamboo" rather than "bamboo" to avoid being misleading about the nature of the fabric.
(A Bum Genius bamboo fitted - these are thick and soft, but are discontinued so you will only find them used on FSOT)
Bamboo fabric is very absorbent, and when made into a velour, is incredibly soft. It supposedly has natural antimicrobial properties that help it to not stink or grow bugs. However, it can sometimes stain more easily than other fabrics. Most bamboo fabrics need to be washed a number of times before they reach their full absorbency.
Hemp. Another natural fiber used in cloth diapers is hemp. Hemp is also very absorbent and is used quite a bit for the inner absorbent material in fitteds, and also comes in inserts for pockets. We use a hemp insert as part of our nighttime system. Hemp coupled with microfiber is pretty bulletproof for nighttime. I recently got some hemp prefolds that are thick and squishy and soft. I love them, but they are too pricey to buy any more right now.
(A hemp prefold over a GMD red for size comparison. This is from Knickernappies.)
Microfiber is a synthetic material used for pocket inserts. It is very very very (did I say very) absorbent. So much so, that you can not put microfiber next to your little ones skin. It will absorb the skin's moisture and cause redness and rashes. Microfiber absorbs fluid quickly, but can sometimes leak when pressure is applied ("compression leaks") like in a car seat. Microfiber also can sometimes get "the stinks" but I think that depends on your laundry routine. I have been using microfiber inserts for 10 months now with no stinks. But I don't use natural laundry detergent, either.
Partnering microfiber with hemp is a good system. The microfiber absorbs quickly. The hemp absorbs more slowly, but "stores" the fluid so it doesn't leak under compression. The new Thirsties Duo Diapers have a two-layer insert that snaps together - one layer is microfiber and the other layer is a hemp/cotton blend. Works like a charm.
PUL - this is the fabric that forms the waterproof layer of covers, pockets, and all-in-ones. It stands for polyurethane laminated, and is usually a laminated polyester fabric.
Wool - can be knit/crocheted or interlock. Interlock is used for covers, including pull-on covers, wrap-style covers, or interlock shorties and longies. Wool yarn can be knit or crocheted into longies, shorties, skirties, or soakers (a pull-on style cover). I did a whole post on wool previously - check the tags.
Fleece - used a couple of different places in cloth diapers. One, it can be used as a cover. There are fleece covers and fleece pants. Polyester fleece usually has a slight water resistant property, so it can be used as a cover, but usually does get damp and has to be changed after each wet diaper. For this reason they are usually called fleece "soakers". Two, fleece is usually used as the lining to pocket diapers to form the "pocket" that you stuff. Since fleece has this water-resistance to it, the moisture goes through the fleece to the insert to be absorbed, and the surface of the fleece feels fairly dry - so it is often called "stay dry" fleece. I have had people re-use the same diaper on wee one because it felt dry to them for this reason. Third, fleece can be used as liners in any kind of diaper. The idea is the same - it has this "stay dry" feeling to it. Diaper cream can ruin cloth diapers, but sometimes it is necessary even for a cloth diapered little one. In this case you can use small pieces of cheap fleece as "liners" to protect the inside of the diaper from the diaper cream, and to wick moisture away from the diaper area. Other mamas that don't like to deal with messy poo diapers use the fleece liners and have a different washing routine for them. They can also be used inside prefolds, which are cotton and can feel drenched when wet, for the "stay dry" effect.
Zorb - this is a new synthetic fabric that was going to transform the cloth diapering world. Only it didn't. It's ok. It's not nearly as absorbent as the hype would lead you to believe. It has to be sandwiched betweeen other absorbent layers like bamboo, which makes it bulkier than a single layer. But it doesn't have the stink issues that microfiber does. I have some bamboo/zorb inserts that we like to use as doublers in fitteds, or for extra overnight layers, and they work well.
Similar to what I said in the first CD 101 post - if you know WHY you are looking into cloth diapering, it helps you narrow the choices. Cotton is cheap, bamboo, hemp, and wool are more expensive. If you want all natural, you are gonna need to look at wool covers. If you want organic, you can find it, but you will pay more for organic diapers. If you want cute, lots of mamas make fitteds with cute knit outers and cotton velour or bamboo velour (soft!) insides, so you can enjoy the outside and your baby can enjoy the inside.
I'm hoping that the discussion about diaper types in the first post and fabrics in this post has helped give an outline of the choices in cloth diapering. I love to talk to moms considering cloth diapering about their options, so feel free to post a comment or send me an email, and I'll see if I can help.