Brynje Thermo Mesh Review (Wool and Synthetic Base Layers)

Introduction

Brynje (pronounced brin-ya) is a Norwegian company specializing in base layers with an open-weave construction (as opposed to a traditional, fine-knit construction). In an open-weave ("fishnet") construction, perspiration vapor can be rapidly transported to outer layers. This is In contrast to solid knit construction, where perspiration vapor tends to (first) condense onto the fibers and then must be "wicked" to the outer layers.

The idea is that open-weave fabric dries faster, breathes better, and offers a higher insulation-to-weight ratio than traditional base layers. Brynje also claims that its woven products are more durable than conventional base layers.

Brynje’s products come in a range of designs and material blends. For this base layers review, I got my hands on four products:

• Unisex Wool Thermo T-Shirt Base Layer with Inlay
• Unisex Wool Thermo Light Longs Base Layer with Inlay
• Unisex Super Thermo T-Shirt Base Layer with Inlay
• 70 Gram Wool Hat

At this point, since nomenclature can sometimes be confusing, it's important to note that:

• Wool Thermo is a blend of (predominantly) merino wool and nylon (for durability).
• Super Thermo is a polypropylene fabric (lowest water absorption).
• Inlays are solid fabric panels that have been sewn into the shoulders of torso garments (for more comfort under a pack strap) and into the crotch panels of leggings (presumably, for some measure of modesty).

Together these products form a complete base layer sleep system (minus socks) and represent a well-rounded sampling of Brynje’s design aesthetic, manufacturing quality, and material choice.

Photo: Brynje. Top left - Unisex Wool Thermo T-Shirt Base Layer with Inlay. Top right - Unisex Wool Thermo Light Longs Base Layer with Inlay. Bottom left - 70 Gram Lined Hat. Bottom right - Unisex Super Thermo T-Shirt Base Layer with Inlay.

Features and Specifications

Features

• Wool Thermo T-Shirt
  • Open-weave mesh fabric
  • Wool/synthetic blend
  • Solid knit inlay at shoulders
  • Long cut falls well below the waist
  • Drop hem (in addition to long cut)
  • Snug, athletic fit - very stretchy
  • Unisex
• Super Thermo T-Shirt
  • Open-weave mesh fabric
  • Synthetic
  • Solid knit inlay at shoulders
  • Drop hem
  • Snug, athletic fit - very stretchy
• Wool Thermo Light Longs (leggings)
  • Open-weave mesh fabric
  • Wool/synthetic blend
  • Solid knit inlay at crotch and knees
  • Elastic bands at waist and ankles
  • Snug, athletic fit - very stretchy
  • Unisex (no fly)
• 70 Gram Lined Hat
  • Open-weave mesh liner
  • Knit wool/synthetic blend shell
  • Extra fabric available for pulling down over ears and neck
  • Snug fit, slightly stretchy

Specifications

• Wool Thermo T-Shirt (size medium)
  • Weight (claimed): 3.9 oz (110 g)
  • Weight (measured): 4.2 oz (119 g)
  • Material: 80% merino wool and 20% polyamide
  • Fabric: knit, 3/8 in (1 cm) open-weave mesh, 3.7 osy (125 gsm)
• Super Thermo T-Shirt (size small)
  • Weight (claimed): 3.9 oz (110 g)
  • Weight (measured): 4.0 oz (113 g)
  • Material: Schoeller® Polycolon® synthetic yarn (polypropylene)
  • Fabric: knit, 3/8 in (1 cm) open-weave mesh, 4.1 osy (140 gsm)
• Wool Thermo Light Longs (leggings) (size small)
  • Weight (claimed): 5.2 oz (150 g)
  • Weight (measured): 4.2 oz (119 g)
  • Material: 80% merino wool and 20% polyamide
  • Fabric: knit, 3/8 in (1 cm) open-weave mesh, 3.7 osy (125 gsm)
• 70 Gram Lined Hat (size large)  
  • Weight (claimed): 2.5 oz (70 g)
  • Weight (measured): 2.4 oz (68 g)
  • Material and Fabrics:
    • Shell: solid knit, 80% merino wool and 20% polyamide
    • Lining: knit, 3/8 in (1 cm) open-weave mesh polypropylene Super Thermo Mesh

Review Context

Clothing in the outdoor industry seems susceptible to hard-to-prove, occasionally outrageous claims. Just recently, Smartwool released Intraknit, which they claim is “the biggest innovation in apparel manufacturing in 200 years*.”

Bold talk - but representative of the kind of hyperbole the outdoor industry seems to reserve for apparel. Brynje is a little less extreme with their advertising copy. But they still claim that their open-weave concept dries faster, is more robust, and provides the same warmth for less weight than solid knit base layers.

Lounging around camp in the Brynje 70 Gram Hat. An inner Super Thermo Mesh lining and a wool/poly outer layer combine for a warm head garment - essential for those of us with no natural head insulation. Also pictured here: the Tarptent Stratospire Li and Helinox Chair Zero.

I tested these claims as well as I could outside of laboratory settings. Like most serious backpackers, I’m a long-time user of base layers. I tend to hike in them in addition to sleeping in them. I hike hot, so I like the breathability and comfort that a base layer affords as a primary hiking garment.

In 2012 I completed a thru-hike of the Appalachian Trail while hiking and sleeping in Patagonia’s synthetic Capilene Cool base layer system (at the time it was called Capilene One). Since then, I’ve completed a few more thru-hikes and dozens of shorter trips in Smartwool and Icebreaker base layers.

I’m a fan of wool or wool-blend base layers. But apparently, my sweat is slightly acidic, and when combined with pack-strap abrasion and bushwhacking, thinner wool knit garments tend to rot off my body within a few months of heavy use. I wish I had pictures of the lower back, belly, and underarm holes in all my merino base layers, but my wife has permanently banished these offensive items of clothing from our cabin.

So, while I was interested in testing Brynje’s warmth, comfort, and fast-drying claims, I was particularly excited to see how the products held up over a long period of backcountry use. I tested these four garments in various configurations and situations over a year of sleeping and hiking - mostly in alpine zones in California and Montana.

Where to Buy

• You can buy Brynje base layers and other accessories here.

Related Content

• Ryan Jordan wrote a comprehensive skills article about why and how to incorporate fishnet base layers into your clothing system.
• Read Jӧrgen Johansson’s article on base layers here.
• Dave Chenault offered a prophecy about the future of base layers a few years ago - has the future arrived?
• Backpacking Light has been doing base layer performance research for a long time. Here's a classic.

Disclosure

Updated October 28, 2019

• Product(s) discussed in this article may have been purchased by the author(s) from a retailer or direct from a manufacturer, or by Backpacking Light for the author. The purchase price may have been discounted as a result of our industry professional status with the seller. However, these discounts came with no obligation to provide media coverage or a product review. Backpacking Light does not accept compensation or donated/discounted products in exchange for guaranteed media placement or product review coverage.
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