Whether in an anorak, quarter zip top or pullover hoodie form, fleece is a versatile fabric made from polyester that actively traps heat to keep us warm. Whichever form you pick, fleece garments are generally worn as a mid-layer for added warmth, underneath a down or shell on days you need extra protection against the elements. Different fleeces are built for different purposes, each with varying capabilities and features.
A Little Bit of History
Textile manufacturer Malden Mills® (now Polartec®) created a hydrophobic textile to mimic wool between 1979 and 1981. This synthetic fabric was manufactured to provide all the warming capabilities of wool without its downfalls. It’s lighter, more packable, remains lightweight and insulating when wet and feels soft without the itchiness of wool. Plus, it’s machine washable.
During this time, Patagonia discovered this fleece fabric and created its first fleece garment in 1985 for mountain climbers—the Synchilla Snap-T Fleece Pullover. With a buttoned standup collar and classic snap chest pocket, this pullover was an instant hit and remains a fan favourite today for a variety of outdoor pursuits.
By the late 1990s, fleece became more than just for outdoor adventurers, and the material was used to craft fleece products of all kinds to defend against the cold, like throw blankets, pajamas and scarves. Because of its availability and affordability, fleece became a popular option for staying warm. For outdoor enthusiasts, its flexibility, breathability and insulating properties even when wet make it an attractive option for high-output activities.
Different Types of Fleece
Fleece garments are manufactured with different weights and features that provide varying levels of warmth for backcountry and front-country use. The fabric is categorized by weight in grams per square metre (gsm), or how many grams of fleece make up a single square metre. Most outdoor clothing companies use the Polartec scale of 100, 200 and 300. The higher the number, the warmer and heavier the garment. This number can usually be found in the product description.
Generally, any fleece up to 200 gsm is categorized as a microfleece. It’s the thinnest and lightest in weight. And though it provides the lowest level of insulation among the fleece types, it allows for the greatest flexibility and highest breathability, which makes microfleece ideal for active pursuits like hiking, running, skiing and climbing in mild climates. Because microfleece is crafted mainly for high-output activities, it tends to embody simple designs, free of any hand or chest pockets and hoods. Microfleeces are ideally worn as mid-layers or as outerwear only in very mild climates or on summer days. Garments made of microfleece can feel as thin as a t-shirt.
Fleece between 200 and 300 gsm is considered to be midweight fleece and is the most versatile and common fleece type. It's an all-arounder and ideal for everyday wear, and because of its extra weight and insulation, it's thick enough to wear as an outer layer on a dry but chilly day. On wet or windy days, a midweight fleece can still be worn underneath a shell. Because a midweight fleece offers less flexibility than a microfleece, midweight fleeces are ideal for activities where you still require ease of movement but are not high-output activities, like a light hike or car camping. A midweight fleece has medium thickness so it feels like your average sweater. An example is the Patagonia Better Sweater.
As its name suggests, heavyweight fleece is the heaviest in the range and comes in at 300 gsm or more. It's best suited for the coldest conditions and tends to work well as a standalone jacket due to the thickness/bulkiness. Though heavyweight fleece is the most insulating, it's the least flexible of the range, which makes it best suited for conditions where physical activity and movement are limited, like winter walking. Pursuing high-output activities while wearing a heavyweight fleece could leave you feeling overheated.
Textured fleece, like teddy and sherpa, shares the same weight range as heavyweight fleece. This type of fleece features a three-dimensional patterned design, but this is more for appearance and style rather than function. This Mountain Hardwear HiCamp Shell Jacket pairs high-loft sherpa fleece liner with a weather-resistant shell, making it versatile as well as stylish.
Extra Features To Look For
Some fleece garments come with extra features to help maximize their performance and reduce the number of layers you have to wear or pack with you by adding to their versatility. Because fleece isn't windproof, some garments, like The North Face Denali Jacket, come with a nylon overlay to block wind from the chest and shoulders for extra warmth. Other features, like elastic bindings at the hem and cuffs, and a raised collar, help seal out the cold so you can get cozy in fleece this winter season.