What wool is
Wool is the fiber that grows on sheep. After shearing, it is cleaned, combed or carded, spun into yarn, and woven or knitted into cloth. Its structure makes it behave differently from plant fibers: it is naturally crimped, which traps air and helps it insulate, and its surface is covered with microscopic scales that make it likely to felt when agitated.
The word “wool” is also used more loosely for fibers from other animals, such as goats or alpacas, but those usually have their own names and character. This article focuses on sheep’s wool.
What wool does well
- Insulates. The crimp traps air, so wool keeps you warm even in relatively thin layers.
- Handles moisture. Wool can absorb a fair amount of moisture vapor without feeling wet, and it often stays comfortable in damp conditions.
- Resists odor, so a wool garment can often be aired between wears instead of washed after each use.
- Bounces back. The fibers are elastic, so wool garments tend to resist wrinkling and recover their shape.
- Takes many forms. It appears in thin sweaters, socks, suiting, coats and blankets.
Where it can disappoint
- Some wool feels scratchy against sensitive skin.
- It can shrink or felt when washed in hot water or agitated.
- It can attract moths if stored dirty.
- Fine wool can wear out sooner if rubbed constantly.
- It may be pricier than synthetics or cotton, as discussed in why clothing prices vary.
Fineness is the key idea
The main difference between wool types is how thin the fibers are. Thicker fibers poke at nerve endings in the skin, which many people feel as itch or prickle. Finer fibers bend more easily and feel softer. That is why a soft sweater and a rugged one can both be labeled wool.
Common types of wool
Merino
Merino comes from a breed of sheep known for producing very fine wool. Because the fibers are thin, merino is often soft enough to wear against the skin. It is common in base layers, T-shirts, socks and lightweight sweaters.
Typical traits: soft, light for its warmth, good with moisture and odor. It is usually more delicate than coarser wools, may pill, and can be more expensive. Like all wool, it benefits from gentle care.
Lambswool
Lambswool is traditionally wool from a young sheep’s first shearing. It tends to be soft and light, although it is generally not as fine as top-grade merino, and the term is used somewhat loosely. It is common in sweaters and scarves.
Typical traits: soft and warm with a slightly fuzzy surface, comfortable for daily wear, but prone to pilling and less hardwearing than coarser wool.
Other wool types
Many other sheep breeds produce wool that is coarser and sturdier. It is often used for outerwear, heavy sweaters, rugs and tweed-like cloth. These wools tend to be hardwearing and very warm, but may feel rougher. Wool described as “rustic” or “traditional” often falls into this category.
Wool blends
Wool is often blended with synthetic or other natural fibers. Nylon or polyester can boost strength, while cotton or silk can alter feel. Check the label percentages, since the blend determines care, and read up on how fiber blends behave.
Weaving and knitting
Wool is used in both knit and woven forms. Fine knits make sweaters and base layers. Woven wool makes trousers, skirts, blazers and coats. Smooth, closely woven wool, often called worsted, is used for suiting and holds a crease, while fuzzier woolen yarns make softer, airier cloth. The difference between knit and woven cloth is explained in a separate guide. Knits are part of a larger story told in the account of knitwear evolution.
Everyday wearability
- Base layers and T-shirts. Fine merino suits skin contact and varied weather.
- Sweaters and cardigans. Lambswool and merino are comfortable options, and cardigans are easy to style and layer.
- Trousers and blazers. Woven wool is a classic for office style and holds its shape well, which also makes it a mainstay for wearing blazers.
- Coats. Thicker wool provides warmth and wind resistance.
- Socks. Wool is widely used because it stays comfortable in changing temperatures.
If a wool sweater feels itchy, a thin cotton or silk layer underneath may help. Trying garments against the neck or wrist before buying is a quick comfort test.
Care in brief
Always follow the care label. As general guidance:
- Wash less often than other fabrics, and air garments between wears.
- When washing, use cool water, gentle detergent and minimal agitation. Hand washing or a wool cycle is often suggested.
- Avoid wringing. Reshape wet knits and dry them flat.
- Avoid hot dryers, which can shrink wool.
- Remove pilling gently by hand or with a suitable tool.
- Store wool clean and folded, in a breathable container, and see tips on seasonal storage to reduce moth risk.
With some care, wool garments can last for many years, which makes them a candidate for building timeless pieces into a wardrobe.