From unlikely origins in toilet seats, fleece-based clothing has come on leaps and bounds over the decades – and now mid-layers come in a huge variety of styles. David Lintern and Lucy Wallace put some of the best to the test.

There’s a wide variety of mid-layer designs to choose from, from fleeces to softshell-style ‘active insulation’. The aim is to strike a balance between warmth, breathability and wicking, depending on your activity and expected weather conditions.

Here’s what to look for if you’re in the market for a new mid-layer. Lucy Wallace puts five of the best women’s garments to the test, and then David Lintern does the same for men’s.

Pockets

Napoleon or bicep pockets are good for smaller items. Torso pockets are larger but all can interfere with harnesses and rucksack straps so check fit.  Zips keep things safe inside.

Hood

Provides extra warmth on cold days, but can be a faff under other layers.

Front Zip

Full length or not… You decide! Some are sold as “interactive” zips that combine with a waterproof to make a padded 2-in-1 jacket.  The downside to this system is a cold spot down the front where the zips meet.

Fit

Close fitting stretchy fleeces are good for layering underneath other garments.  Length helps keep vital organs warm and prevents riding up.

Cuffs

Some have a hook and loop tab or thumb loops to deal with drafts.

Hem

Stretchy edge finishing or a drawcord help to keep drafts out and prevent riding up, but check the drawcord/toggle wont chafe under your rucksack.


5 women’s mid-layers for 2021 reviewed

BEST BUY: Haglöfs Women’s Heron Hood (RRP: £130)

Haglöfs Women’s Heron Hood

Rating: 5/5

Likes: Stretch fit, roomy pockets, eco credentials

Dislikes: Nothing

Weight: 315g | Insulation: 238 g/m² Pontetorto Technotretch- 93% recycled polyester 7% elastane | Sizes: XS-XXL | Mens version: yes

It’s not often that I come across a garment that I love unconditionally, but the Heron Hood from Haglöfs is near faultless. Once I’m wearing it, I forget about it, thanks to zero discomfort or niggles.

Read more: Haglöfs Women’s Heron Hood

Sherpa Santi Full Zip (RRP: £60)   

Sherpa Santi Full Zip  

Rating: 3/5

Likes: Eco credentials, price,

Dislikes: No zips on pockets

Weight: 360g | Insulation: Brushed French terry- 63% recycled polyester, 33% Rayon, 5% Spandex | Sizes: XS-XXL | Men’s version: no

A less technical garment than the others reviewed in this issue, it still does a good job as an insulating layer, albeit with more of an emphasis of aesthetic rather than functional details.

Read more: Sherpa Santi Full Zip review

RECOMMENDED: Salewa Pedroc Polarlite  (£119.70)

Salewa Pedroc Polarlite Rating: 4/5

Likes: Great wicking performance

Dislikes: Saggy pockets when in use

Weight: 360g | Insulation: 263 g/m² Polarlite Responsive 95% polyester 5% elastane | Sizes: 4-14 | Men’s version: yes

This is a very light and breathable grid style fleece that performs particularly well in situations where the body is pumping out a lot of heat and sweat, but still needs the insulation of a fleece. The smooth face fabric and flatlocked seams mean it would work as part of a bigger layering system, but the lightweight breathability is ideally suited to milder conditions.

Read more: Salewa Pedroc Polarlite review

RECOMMENDED: Montane Women’s Protium Hoodie (£65)

Montane Women’s Protium Hoodie

Rating: 4/5

Likes: Wicking performance, good value

Dislikes: Pocket positioning

Weight: 334g | Insulation: Thermogrid 93% polyester 7% elastane | Sizes: 8-16 | Men’s version: yes

Montane can generally be relied upon to produce high performance gear at a price that is accessible to most people, and they have done exactly this with the Protium hoodie.

Read more: Montane Women’s Protium Hoodie review

RECOMMENDED: Fjällraven Keb Hoodie W (£185)

Fjällraven Keb Hoodie W

Rating: 4/5

Likes: Durable, warm, eco credentials

Dislikes: Price, weight

Weight: 485g | Insulation: 73% Polyester 20% Wool, 7% Elastane & G-1000 Eco – 65% polyester, 35% cotton | Sizes: XXS-XXL | Mens version: yes

The addition of wool to the fleece mix adds weight but also durability.  Wool is a renewable material, unlike fossil fuel derived virgin polyester.  Fjällraven have made an effort to reduce their environmental footprint, and the polyester is described as part recycled, although what percentage, is unclear.

Read more: Fjällraven Keb Hoodie W review

Testing note: I tested these fleeces on multiday expeditions with mixed weather, ranging from hot, to windy to absolutely chucking it down. The weights supplied were measured on my home digital scales.


5 men’s mid-layers for 2021 reviewed

BEST BUY: Montane Allez Micro (£70)

Montane Allez Micro

Rating: 4.5/5

Likes: Versatility, comfort

Dislikes: Sizing

Weight: 160g | Insulation: Polartec Power Grid | Outer: None | Sizes: Various | Women’s version: Yes

The Allez Micro has been around for a while now and won lots of fans, myself included. It’s the lightest mid layer in my test, and the main ingredient is Polartec Power Grid, which has a smooth outer face and a ‘dotted’ inner. This structure imparts warmth (from the dots) and plenty of breathability elsewhere. This version keeps things simple with only a zip at the neck, but a hooded version is also available. The material is 90% recycled.

Read more: Montane Allez Micro review

RECOMMENDED: Arcteryx Atom SL (£180)

Arcteryx Atom SL

Rating: 4/5

Likes: Versatile, 2-in-1 active insulation

Dislikes: No chest pocket

Weight: 270g | Insulation: Coreloft | Outer: Tyono 20, DWR finish | Sizes: various | Women’s version: yes

The Atom SL is the odd one out in this selection, sitting in the newer generation of mid layers that aim to do more than one job at a time. The key player here is the brand’s own insulation called Coreloft, a non-woven siliconised polyester in sheet form, that traps heat and does not retain water.

Read more: Arcteryx Atom SL review

Salewa Tognazza (£100)

Salewa Tognazza jacket

Rating: 3.5/5

Likes: warmth, wicking, price

Dislikes: taped hems, no chest pocket

Weight: 420g (medium) | Insulation: Polarlite Mélange | Outer: None | Sizes: Various | Women’s version: No, but others similar

A good price for this exceptionally warm, technical offering from Salewa. The main fabric is the brand’s own Polarite Melange, a hi loft, fluffy fleece which is mapped in two different thicknesses, with the inside arm being lighter to assist breathability. The hood is close fitted (will sit under a helmet) and all hems are taped. There are two, deep torso pockets but no chest pocket.

Read more: Salewa Tognazza review

RECOMMENDED: Fjällräven Abisko Trail Fleece (£135)

Fjällräven Abisko Trail Fleece

Rating: 4/5

Likes: Versatility, comfort

Dislikes: Nothing

Weight: 390g | Insulation: Zoned polyester | Outer: None | Sizes: Various | Women’s version: Yes

The Abisko is a smart looking fleece hoody made with modern materials. The polyester is mapped for warmth and breathability where it’s needed – hood, shoulders and chest get a part recycled, low loft brushed fleece, and the sides, lower torso and lower arms are finished with a grid pattern to improve ventilation. There are two deep torso pockets (low enough to interfere with a hip belt) and one chest pocket that easily swallows a smartphone. Overall, the fit is relaxed, but when fully zipped up to the nose, the hood becomes closer fitting and gives ample protection.

Read more: Fjällräven Abisko Trail Fleece review

RECOMMENDED: Patagonia R1 Air Hoody (£130)

Patagonia R1 Air Hoody

Rating: 4.5/5

Likes: Warmth, comfort, breathability

Dislikes: Tiny chest pocket

Weight: 370g | Insulation: jacquard polyester | Outer: none | Sizes: various | Women’s version: yes

The original R1 earned plenty of accolades in winter sports and mountaineering circles, and for good reason. It wicked well and provided tons of warmth. The R stands for ‘regulator’ – and it did have a reputation for being a mid you could keep on all day.

Read more: Patagonia R1 Air Hoody review