What Is Polar Fleece?
Polar fleece is a soft, lightweight, napped knit fabric made from polyester. A knitting machine forms a jersey-style knit, and the surface is then brushed on one or both sides to raise a fuzzy pile of fibre ends, which is sheared to an even height. The raised layer traps air, so polar fleece feels warm for its weight. Because polyester absorbs very little moisture, polar fleece also dries quickly, which is a large part of its appeal in jackets and mid layers.
The name is used loosely. Polar fleece, fleece and microfleece are often treated as the same thing, and brushed-back cotton fleece, the kind used in most hoodies, is sometimes also called fleece. Because they behave differently, always state the fibre and the construction in your specification. Our guide to polyester fabric covers the fibre side.
The sections below start with how polar fleece is made, then move to sherpa, the comparison table, weights, performance and the practical issues of pilling, static and recycled content.
How Polar Fleece Is Made
Polar fleece begins as polyester yarn, often a textured or staple yarn that has bulk. The yarn is knitted into a fabric, commonly on a circular knitting machine, and the fabric is dyed. It is then passed through brushing machines that lift fibres from the loops, and shearing machines that trim the raised surface to a consistent height. Finishing steps may include setting the width, applying an anti-pill treatment and heat setting.
From yarn to finished polar fleece
- 1KnitPolyester yarn is knitted into a base fabric, usually on a circular machine.
- 2DyeThe fabric is dyed in the piece; polyester needs disperse dyes at high temperature.
- 3BrushRollers lift fibre ends on one or both faces to build the pile.
- 4Shear and finishThe pile is cropped for evenness, and anti-pill and softening finishes are applied.
- 5InspectThe roll is checked for weight, width, shade and surface faults.
A generic sequence. Mills may reorder or add steps, for example an anti-pill pass or bonding.
Each stage affects the result. The quality of the yarn, the density of the knit and the amount of brushing decide how plush the cloth feels and how well it keeps its surface after washing.
Types of Polar Fleece: Microfleece, Anti-Pill, Double-Faced and Bonded
Polar fleece is made in several versions, each aimed at a different use. Knowing the vocabulary helps when you read a supplier quote, because a single price may not be comparable across types.
Common polar fleece types
| Type | What it is | Typical use | Points to check |
|---|---|---|---|
| Microfleece | Lighter, finer-fibre polar fleece with a smooth, dense surface | Base layers, light jackets, accessories, linings | Thin cloth shows seams; check opacity and pilling |
| Standard polar fleece | Midweight brushed polyester knit | Jackets, pullovers, blankets | Pile height and softness after washing |
| Anti-pill polar fleece | Surface treated or constructed to limit the formation of pills | Uniforms, outerwear, frequently worn garments | Ask for pilling test results, not only a label |
| Double-faced fleece | Brushed on both sides; sometimes two different faces | Reversible jackets, blankets | Weight and bulk at seams |
| Bonded fleece | Fleece laminated to another layer such as a woven or membrane | Outerwear and technical jackets | Adhesive, delamination and breathability |
General descriptions. Names and treatments vary between mills.
Bonded fleece is technical and sits at the outerwear end of the market. For ordinary casual garments, brushed-back fleece knits are far more common, which is why hoodie fabric choices start with cotton and poly-cotton rather than pure polyester.
What Is Sherpa Fabric?
Sherpa fabric is a pile fabric designed to resemble the curly wool of a sheep. It is most often made from polyester, though acrylic and cotton versions exist. The deep, curled pile is typically produced either by knitting and then brushing, or by a looped or curled pile structure, and it is commonly bonded or knitted to a smooth backing so that the pile faces out on one side only. The term is also written as borg, teddy fleece or faux shearling in different markets.
The look is the main difference. Polar fleece has a short, flat nap, while sherpa has a thick, curly, textured surface that reads as cosy. That texture is why sherpa features in collars, hood linings, jacket linings and blankets, and why it is often combined with another outer fabric. Our guide to boucle fabric covers a related textured surface in woven and knit form.
Sherpa, borg and teddy are used loosely by suppliers and shoppers. Specify the pile height, the fibre, the backing and the weight, and ask for a physical swatch, rather than relying on a name.
Polar Fleece vs Sherpa vs Cotton Fleece vs French Terry
Choosing between these fabrics is mainly a choice between synthetic pile and cotton-based knit. The table compares them across the factors that matter in product development.
Four warm knits compared
| Property | Polar fleece | Sherpa | Cotton or poly-cotton fleece | French terry |
|---|---|---|---|---|
| Fibre | Polyester | Usually polyester, sometimes acrylic or cotton | Cotton or cotton-polyester | Cotton or cotton blends |
| Surface | Short brushed nap | Deep curly pile on one face, smooth back | Brushed on the inside, smooth knit outside | Loops on the inside, smooth knit outside |
| Warmth for weight | High | High to very high | Moderate to high | Moderate |
| Breathability | Lower | Lower | Higher | Highest of the four |
| Drying speed | Fast | Moderate to fast | Slower | Moderate |
| Typical garments | Jackets, pullovers, blankets | Collars, linings, outerwear, blankets | Hoodies, joggers, sweatshirts | Lightweight sweats, hoodies, joggers |
General tendencies. Weight, construction and finishing shift every row. Read more in our French terry fabric guide.
If your brand makes hoodies and joggers, cotton or poly-cotton fleece and French terry will usually be the main fabrics. Polar fleece and sherpa are used when you want a deliberately synthetic, quick-drying or plush surface.
Polar Fleece and Sherpa Weights: Typical GSM Ranges
Fleece weight is quoted in grams per square metre (GSM). Lightweight microfleece suits base layers and accessories, midweight polar fleece suits jackets and pullovers, and heavy or sherpa-backed cloth suits outerwear and linings. The chart shows typical bands for orientation. Real weights depend on the mill, pile height and finish.
Typical weights of pile and fleece fabrics
Typical grams per square metre
Typical ranges only; they vary by product, mill and market. Sherpa weight depends heavily on the pile and the backing.
Weight alone does not tell you the warmth or the feel. Two fleeces at the same GSM can feel very different if one has a taller, softer pile and the other a dense, flat nap. Our fabric GSM guide explains how to read weights sensibly.
Indicative Ratings: How the Fabrics Perform
The chart gives a quick, indicative comparison of the three most requested pile fabrics. It is general guidance, not laboratory data.
Pile fabrics compared (indicative)
1 dot = low, 5 dots = high
| Polar fleece | Sherpa | Cotton fleece | |
|---|---|---|---|
| Warmth for weight | ●●●●● | ●●●●● | ●●●●● |
| Softness on the skin | ●●●●● | ●●●●● | ●●●●● |
| Breathability | ●●●●● | ●●●●● | ●●●●● |
| Quick drying | ●●●●● | ●●●●● | ●●●●● |
| Pilling resistance | ●●●●● | ●●●●● | ●●●●● |
| Static resistance | ●●●●● | ●●●●● | ●●●●● |
Indicative ratings based on typical fabric/process characteristics, not laboratory results.
Synthetic pile fabrics are strong on warmth and drying speed. Cotton-based fleece is stronger on breathability and static, which is why it remains the default for hoodies and joggers.
Pilling, Static and Microfibre Shedding
Three issues come up repeatedly with polar fleece. The first is pilling. Fleece has a lot of loose fibre ends, and polyester is strong enough to hold the tangled pills on the surface instead of letting them break off. Anti-pill finishes, lower-fibre-end yarns and shearing can reduce the effect, and the standard approach is to test the finished fabric. Our fabric pilling guide explains the causes and test grading.
The second is static. Polyester absorbs very little moisture, so it accumulates static charge easily in dry air, and fleece can attract lint, hair and dust. Anti-static finishes exist but may wash out. The third is microfibre shedding. Synthetic fabrics release tiny fibres in washing and wearing, and brushed or napped surfaces are generally considered to release more. The exact amounts depend on the fabric and the wash, so treat shedding as a real consideration, and ask suppliers what finishing and filtration advice they can offer.
Many fleeces are made from recycled polyester. Ask for verification such as Global Recycled Standard (GRS) documentation, and remember that recycled content does not remove shedding or end-of-life questions. See our guide to sustainable fabrics for how to read such claims.
Cutting and Sewing Polar Fleece and Sherpa
Fleece is forgiving to sew because it does not fray, but pile fabrics create practical production issues that are worth specifying. Pile direction matters: the nap lies one way, so all pattern pieces should be cut in the same direction for even shade. Cutting produces a great deal of lint, which needs managing so it does not clog machines or contaminate other work. Bulk builds up at seams and hems, especially in sherpa, so seam types and allowances are chosen to keep joins flat.
Sewing and cutting checks for pile fabrics
- All pieces cut with the pile running in the same direction
- Needle, thread and stitch length tested on the actual fabric
- Seam type chosen to limit bulk, such as flat or covered seams
- Pressing avoided or kept at a safe low temperature, since polyester is heat sensitive
- Lint controlled at cutting, sewing and packing
- Zips, pocket bags and trims checked for snagging in the pile
Raise these at the sample stage. Many bulk problems start as unspecified sample choices.
Zippers and trims can catch in sherpa pile, and bulky linings change how a collar or hood sits, so a wearing test on the sample is worth doing before bulk.
Where Polar Fleece and Sherpa Are Used
Polar fleece has long been a staple of casual and outdoor mid layers, jackets, scarves, hats, gloves and blankets. Sherpa is common in collar linings, hood linings, jacket linings, slippers and cosy outer layers. Garment makers often combine the two with a woven or knit outer shell: a smooth outer face with a sherpa lining gives warmth without exposing the pile on the outside.
For branded casualwear, the common applications are a sherpa-lined hoodie or jacket, a zip-through fleece top, and a polar fleece quarter-zip. Printing and embroidery on pile can lose detail, so artwork often sits on a smooth patch or label. Test the decoration on the actual fabric, because a deep pile can hide fine lines.
Care Instructions for Fleece
Fleece is easy to care for, and the care label is short to write. Wash at the temperature on the label, avoid fabric softener because it can coat the pile and reduce warmth, and dry at a low temperature or air dry since polyester is heat sensitive. Do not iron the pile. Washing inside out, or in a laundry bag designed for synthetics, helps reduce wear and shedding. The garment should come out of the wash with the pile still lifted and soft, and a wash test at the sample stage confirms this.
How to Specify Polar Fleece or Sherpa
Write the specification so a mill can quote precisely. Include the fibre content, including any recycled content and its documentation, the construction (single or double faced, bonded or unbonded), finished weight in GSM, pile height or description, backing fabric for sherpa, width, and finishes such as anti-pill or anti-static. Add the tests you want, for example pilling grade after a stated number of cycles, shrinkage after a stated wash, and colour fastness. Our garment testing guide lists the usual tests.
Always approve a physical swatch and a wash-tested sample first, and compare it with the bulk cloth when you receive it. Descriptions like soft and plush are not measurable, so the swatch and the wash result are the real specification.
How Ruhrose Approaches Polar Fleece and Sherpa
Ruhrose develops hoodies, jersey, denim and woven casualwear for UK buyers, produced in Bangladesh. Cotton and poly-cotton brushed-back fleece for hoodies and joggers is core to what we do, and we sample before bulk. Sherpa-lined garments and polar fleece jackets are discussed case by case, because availability depends on the project and fabric source, and fully technical bonded fleece outerwear is outside our core. See our custom hoodie manufacturer guide for how a hoodie project runs.