Understanding Carpet Fibers 101: Wool

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Wool is the most commonly used natural fiber in carpeting. While synthetic fibers comprise the vast majority of the carpet fiber market, wool definitely has its own niche in the marketplace and continues to be a sought-after fiber option.

Characteristics of Wool

Natural fibers such as wool have several key differences from synthetics.

Durability

Wool is a naturally resilient fiber, although not as highly resilient as nylon.

(The term resiliency refers to a fiber’s ability to bounce back after compression.) Being resilient means that wool has good texture retention, which is the ability of the fiber to retain its original appearance. As such, wool carpets are generally pretty durable, although wool’s resistance to abrasion is not as high as that of nylon or triexta.

Wool carpets have been known to last for decades in a home when properly maintained.

High-Maintenance

It does require a bit more work to maintain a wool carpet compared to carpets made of synthetic fibers. Wool carpets must be professionally cleaned by cleaners who have experience in working with wool carpets. As a natural fiber, wool carries a slight risk of shrinking under improper maintenance, so it is imperative that it is treated correctly, by professionals who are familiar with the fiber and who can clean it effectively without damaging the carpet.

Additionally, it is worth mentioning that wool carpet will shed. Wool is a natural staple fiber, and so is prone to shedding. Staple fibers are short, and so many are left “unattached” during the manufacturing process. A number of fibers shed from the carpet will diminish over time, and shedding does not mean that your carpet is falling apart, but it can be bothersome.

Stain Resistance

Wool is less stain resistant than most synthetic fibers. Wool is very absorbent, so it can be difficult to remove stains once they have been absorbed by the fiber. As with all fibers, the best method of preventing a stain when a spill happens is to treat the spill as quickly as possible. If the substance is allowed to soak into the fiber, it may not come out.

Soil Resistance

Soiling is different from staining (learn about the difference here).  Wool does have good resistance to soiling. Because wool is a natural fiber, the fibers have microscopic scales. These scales help to prevent dirt from embedding in the carpet fibers. In addition, the scales disperse light, so that any soiling that does occur on the wool is masked.

Flame Resistance

Wool’s flame resistance is worthy of note because it differs significantly from synthetic fibers in this regard. Wool will not burn; rather it will char (blacken). For example, a lit cigarette dropped on the carpet will likely leave a noticeable mark, but will not cause the carpet to go up in flames.

I typically discourage the installation of carpet right in front of a wood-burning fireplace or stove, due to the sparks that may jump out and land on the floor.

However, if you do choose to have carpet installed around the hearth, wool carpet is likely your best option due to its flame resistance.

Natural Humidifier

As mentioned above, wool is highly absorbent. While this is not a desirable trait when it comes to staining, it can be beneficial for the household environment. When the air is humid, wool carpet will absorb the excess moisture in the air. Consequently, when the air is drier, the fibers will release the moisture, thereby helping to keep the home’s moisture levels in balance.

For exceptionally damp areas, such as bathrooms or damp basements, wool carpet may not be suitable, as it would rarely – if ever – have the opportunity to dry out, and could cause problems associated with the moisture retention, including mildew and mold.

In humid climate zones, with consistent year-round temperature and humidity levels, the use of a dehumidifier in the home would be recommended to avoid the same dangers of mildew and mold.

Cost

No doubt about it, wool is one of the most expensive carpet fibers. Generally, it is much more expensive than synthetics, including high-end nylons. Of course, there are some entry-level wool carpets that are available at lower cost, around perhaps $3 per square foot or so, but many wool carpets will run much higher than that, often upwards of $10 to $15 per square foot.

Last Word on Wool

Wool is seen by many as an investment, which justifies the high price tag. When selected according to household conditions and properly maintained, it is true that wool carpeting can last for many years. However, for busy households prone to spills and high traffic, a synthetic carpet may be more practical.