How To · Fashion · Winter
The Wool Hierarchy: A Guide to Winter Fabrics
Not all wool is created equal, and understanding the fiber is the difference between a sweater that lasts a decade and one that pills by February. Learn how to navigate the shearling, the staple, and the luxury.
5 min read · IrisWinter style is less about the silhouette and more about the integrity of the fabric. If your closet is filled with synthetic blends, no amount of layering will save you from the biting wind. Wool is a miracle fiber—naturally thermoregulating, moisture-wicking, and odor-resistant—but its performance depends entirely on its origin.
Before you invest in your next cold-weather staple, learn to read the fiber composition. From the rugged durability of Shetland to the cloud-like touch of Cashmere, here is how to identify what belongs in your rotation.
A sweater should be an investment in insulation, not a temporary fix for a cold snap.
Merino · 2 minutes
The Daily Driver
Merino wool is the gold standard for base layers and lightweight knitwear. Because the fibers are exceptionally fine, they don’t itch against the skin like traditional wool. Look for a high 'micron count'—lower is softer—to ensure it feels like cotton rather than carpet. It is ideal for layering under a blazer or a heavy coat.
Check the label for 'Superfine' or 'Extra Fine' to ensure long-term comfort.
Shetland · 2 minutes
The Rugged Classic
Shetland wool is harvested from sheep living in the harsh, windy climates of the Shetland Isles. It is naturally coarse, thick, and incredibly warm. This is the wool for a true 'shaggy' sweater that can withstand a winter storm. It is best worn as a mid-layer over a button-down shirt.
If it feels too scratchy, wear a thin cotton undershirt to create a barrier.
Cashmere · 2 minutes
The Luxury Exception
Cashmere is technically a hair fiber, not wool, sourced from the undercoat of specific goats. It is significantly lighter than sheep's wool but provides up to eight times the insulation. Because it is delicate, avoid wearing it under heavy, abrasive denim jackets that can cause friction and pilling.
Hold the sweater up to the light; if you can see through it easily, the knit is too loose and won't last.
Lambswool · 1 minute
The Mid-Range Workhorse
Lambswool is the first shearing of a sheep, making the fibers shorter and softer than adult wool. It holds its shape better than cashmere and is more durable than Merino. It is the perfect 'everyday' sweater for office wear or weekend errands.
Look for a tight, dense knit to prevent stretching at the cuffs.
Wool Blends · 1 minute
The Practical Compromise
Not all blends are bad. A high percentage of wool (80%+) mixed with a small amount of nylon or polyamide can actually increase the garment's lifespan and prevent sagging. Avoid any sweater where the synthetic content outweighs the natural fiber.
If the tag says more than 20% polyester, skip it—it will trap sweat and smell quickly.
How to know it works.
A quality wool garment should feel substantial but not heavy, and it should return to its original shape immediately after being stretched.
Questions at the mirror.
Why is my new sweater pilling?
Pilling is common with natural fibers. Use a sweater stone or a dedicated fabric shaver, not a razor, to gently remove the friction-induced knots.
How do I store these for summer?
Always clean them first. Moths are attracted to skin oils and food particles. Store in breathable cotton bags, never plastic.