Wool is the main component of higher quality pile area rugs, and is widely used in different parts of the world. Although most wool comes from sheep, it can also come from goats and llamas. Wool is generally a creamy white color, but some breeds of sheep produce natural colors such as black and brown. Wool is a resilient material and has greater durability than synthetic fibers. It can absorb and retain dyes amazingly well. Wool is also naturally resistant to fire, water and stains. A major characteristic of wool area rugs is that they naturally resist dust mites which can aggravate allergies. In fact, wool is considered by the medical profession to be hypoallergenic.

Wool is flexible, durable, readily takes on dyes and is easy to handle when it is spun or woven. Perhaps the most important fact about wool is that it is found in abundance in rug and kilim-making regions of the world. As an example, the Qashqae nomads of Central Iran who are considered as a major producer of Persian rugs and Gabbeh, breed sheeps and goats, so the finest quality of wool is always available to them. There are certain breeds of sheep which are more desirable for spinning, like the "Merino" due to its fleece’s special luster and length of fiber. Nevertheless, the domestic fat-tailed sheep bred is the provider of much of the exceptional fleece used in rugs of today. High quality of wool provides buyers with a beautiful, long-lasting rug or kilim.

Wool's scaling and crimp make it easier to spin the fleece by helping the individual fibers attach to each other, so that they stay together. Because of the crimp, wool fabrics have a greater bulk than other textiles, and retain air, which causes the product to retain heat. This is why blankets have traditionally been made of wool. The amount of crimp corresponds to the fineness of the wool fibers. A fine wool like "Merino" may have up to 100 crimps per inch, while the coarser wools like "Karakul" may have as few as 1 to 2. Hair, by contrast, has little if any scale and no crimp, and little ability to bind into yarn. On sheep, the hair part of the fleece is called "Kemp". The relative amounts of kemp to wool vary from breed to breed, and make some fleeces more desirable for spinning and use in rug weaving.

Wool fibers are hollow and easily absorb moisture. Wool can absorb moisture almost one-third of its own weight. Wool absorbs sound like many other fabrics. Wool ignites at a higher temperature than cotton and some synthetic fibers. It has lower rate of flame spread, low heat release, low heat of combustion, and does not melt or drip, it forms a char which is insulating and self-extinguishing, and contributes less to toxic gases and smoke than other flooring products, when used in carpets. Wool carpets are specified for high safety environments, such as trains and aircraft. Wool is usually specified for garments for fire-fighters, soldiers, and others in occupations where they are exposed to the likelihood of fire. Wool is resistant to static electricity, as the moisture retained within the fabric conducts electricity. This is why wool garments are much less likely to spark or cling to the body. The use of wool car seat covers or carpets reduces the risk of a shock when a person touches a grounded object.

It seems like there is no better material than wool to be used in the rug industry as of yet. Or perhaps the durability of natural wool is a major disadvantage for those involved in selling wool rugs. A rug buyer is unlikely to return for the second piece due to the fact that the first piece he bought is going to last a life-time.