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Index: Base Layers

There are a ton of base layers out there, and with all those choices, you might be tempted to just grab one off the shelf. But there are some details worth paying attention to, such as the type of fabric, and the weight, thickness, warmth, and wickability of a particular piece.

To narrow things down a bit for you, and to clarify some of your options, we’ve listed some of our favorite base layers that we wear on any given day in the mountains or around town.

We’ll be adding to this index going forward, but it should give you a head-start in shopping for a new layer.

We’ve split these products up into loose categories based on their material—ranging from pure merino wool, to merino / synthetic blends, to fully synthetic fabrics. We’ve also included an underwear section at the end, with our take on some more athletic underwear options

Also note that most of the wool and wool-blend base layers have a fabric weight listed. This should give you a relative sense of how thin or thick those pieces are. (A fabric with a weight of 150 g/m2 is quite thin, while a 250g/m2 piece will be quite a bit thicker and warmer.)

Wool

Trew Weightless NuYarn Merino T

Fabric Weight: 105 g/m2
Material: 85% merino wool, 15% nylon
MSRP: $65

Luke Koppa reviews the Trew Weightless NuYarn Merino T for Blister Gear Review

Trew Weightless NuYarn Merino T

NuYarn is an interesting take on a merino/synthetic hybrid, and it certainly stands out among the other wool fabrics when it comes to stretch, comfort, and lightweight feel. The NuYarn fabric is the softest and most comfortable of the wool base layers, and it seemed to wick sweat better and absorb less water than the other wool pieces. The fabric averaged about 2 runs before acquiring much of a smell.

Using the lightest version of Trew’s NuYarn fabric, the Weightless NuYarn Merino T is our favorite of the wool base layers here for hot days. As its name suggests, the Weightless NuYarn Merino T feels very light on skin, and it’s easy to forget you’re wearing it. It fits a bit slimmer than what we’d call a “regular” fit, but is looser than the Mons Royale Yamakasi and Smartwool PhD Ultralight shirts.

 

Trew Superlight NuYarn Merino Pocket T

Fabric Weight: 125 g/m2
Material: 85% merino wool, 15 % nylon
MSRP: $69

Luke Koppa reviews the Trew Superlight NuYarn Merino Pocket T for Blister Gear Review

Trew Superlight NuYarn Merino Pocket T

The addition of the stretch-woven pocket makes the Superlight NuYarn Merino Pocket T a great everyday piece, though the performance characteristics of its fabric also make it a strong contender as an all-purpose base layer. Like the Weightless NuYarn Merino T, the Superlight NuYarn Merino Pocket T offers a great blend of breathability, stretch, comfort, and lightweight feel, and also shares a similar, fairly slim fit.

Luke Koppa reviews the Trew Superlight NuYarn Merino Pocket T for Blister Gear Review

Luke Koppa in the Trew Superlight NuYarn Merino Pocket T, St Mary’s Glacier, CO.

 

Smartwool PhD Ultralight Short Sleeve Shirt

Fabric Weight: not listed
Material: Body: 56% merino wool, 44% Polyester; Mesh: 54% Merino Wool, 46% Polyester
MSRP: $70

Luke Koppa reviews the Smartwool PhD Ultralight Short Sleeve Shirt for Blister Gear Review

Smartwool PhD Ultralight Short Sleeve Shirt

The PhD Ultralight Short Sleeve Shirt’s fabric is only ~55% merino, but it maintains most of wool’s performance characteristics while wicking better than the Mons Royale Yamakasi T and being close behind it in terms of odor resistance. Smartwool doesn’t specify the fabric weight, but does say it’s their “lightest weight merino polyester blend,” and it feels like it falls between the Trew Superlight Merino Pocket T and the Mons Royale Yamakasi T in terms of weight. The mesh panels and tiny vents at the back neckline provide a boost of breathability, and even during very hot, sweaty runs, the PhD Ultralight S/S Shirt didn’t feel very wet (thanks to wool’s hydroscopic properties). The fit is slimmer and shorter than the Trew pieces while being effectively patterned for freedom of movement while running.

 

Mons Royale Huxley SS Henley

Fabric Weight: 140 g/m2
Material: 83% merino wool, 13% nylon, 4% elastane
MSRP: $100

Luke Koppa reviews the Mons Royale Huxley SS Henley for Blister Gear Review

Mons Royale Huxley SS Henley

With its 3-button neckline, the Huxley SS Henley is a great option for those looking for an everyday piece that breathes well, doesn’t stink after a few days, and has a slim silhouette. The Mons Royale wool used on the Huxley SS Henley and Yamakasi T does have that very slight itchiness sometimes found in merino wool, but if you haven’t had issues with the feel of the average merino fabric in the past, we think you’ll be perfectly comfortable in these pieces (we stop noticing the fabric after wearing it for a few minutes). Both the Huxley SS Henley and Yamakasi T feature a slim fit, and are also fairly long.

 

Mons Royale Yamakasi T
Fabric Weight: 140 g/m2
Material: 83% merino wool, 13% nylon, 4% elastane
MSRP: $85

Luke Koppa reviews the Mons Royale Yamakasi T for Blister Gear Review

Mons Royale Yamakasi T

The Yamakasi T features the same fabric in the body as the Huxley SS Henley, but includes a merino mesh fabric on the back and underarms. This makes it a better option for more active use, but still doesn’t look out of place as an everyday shirt. The Yamakasi T performed very well in terms of odor resistance, and lasted 3 runs before stinking too bad. One of the seams between the main fabric and the mesh lies right across the shoulder blades, and this was noticeable while running, though it never became a serious chafing issue. Both the Yamakasi and Huxley SS Henley also include a microfiber sunglasses cleaning cloth sewn at the hem, which is a nice bonus feature. Like the Huxley SS Henley, the Yamakasi T has a slim, long fit.

 

WoolX Base Camp Hooded Sweatshirt

Fabric Weight: 160 g/m2
Material: 100% merino wool
MSRP: $69

Jonathan Ellsworth reviews the WoolX Base Camp Hooded Sweatshirt for Blister Review

WoolX Base Camp Hooded Sweatshirt

This “all season 1/2 zip hoodie” has become one of our new favorite base layers for touring. At a weight of 160g/m², this lightweight piece works comfortably next-to-skin, but it can be worn over a thin t-shirt, too, while still being light enough to wear beneath slim-fitting, midlayers (like the Arc’teryx ProCline Hybrid Hoody). We found ourselves using the hood for sun protection more than we thought we would on the skin up, then using it again on the summit if the winds picked up. Lightweight warmth, comfortable feel, a clean style, and a low-profile hood that stays out of your way when not in use.

Jonathan Ellsworth reviews the Woolx Basecamp Hoody for Blister Gear Review

Jonathan Ellsworth in the WoolX Basecamp Hooded Sweatshirt, MT. Cheeseman, NZ.

 

Mons Royale Monsie

Fabric Weight: 190g/m2
Material: 100% merino wool
MSRP: $239.00

It’s the ultimate onesie. The Mons Royale Monsie is awesome, so you should get one. And our full review contains cute puppies, axes, sexy Hawaiian photo shoots, Looney Tunes onesies, and more, so you should read it.

Review of the Mons Royale Monsie, Blister Gear Review

“I don’t always wear a onesie, but when I do, I prefer the Monsie.”

 

Mons Royale Cornice Rollover LS (Women’s)

Weight: 190 g/m2
Material: 100% merino wool
MSRP: $130

Kristin Sinnott reviews the Mons Royale Cornice Rollover LS for Blister Review

Mons Royale Cornice Rollover LS

The Mons Royale Cornice Rollover LS has quickly become one of our favorite go-to base layers, and we’ve really come to appreciate the versatile turtleneck, which can be pulled up and used like a neck gaiter when things get windy, or be left down when not needed. We’d recommend this product to anyone looking for a soft, medium-to-lightweight wool shirt.

 

WoolX Rory Quarter Zip Sweater (Women’s)

Weight: 230 g/m2
Material: Body: 100% 17.5-micron merino wool; Sleeves & Sides: Polyester/Spandex Microfleece
MSRP: $74

Kristin Sinnott reviews the WoolX Rory Quarter Zip Sweater for Blister Review

WoolX Rory Quarter Zip Sweater

The WoolX Rory Quarter Zip Sweater utilizes 230 g/m2 merino wool in the body, and then features microfleece panels on the arms and sides, making it a comfortable mid-weight top. It does run a bit large (we were comfortable in a size down from our standard size) and starts to smell a bit faster than 100% merino pieces, but is a solid layer for anyone looking for a mid-weight base layer for skiing, running, biking or hiking.

Smartwool Merino 250 Base Layer Pattern Crew
Fabric Weight: 250 g/m2
Material: 100% merino wool
MSRP: $100

Jonathan Ellsworth reviews the Smartwool Men’s Merino 250 Base Layer Pattern Crew for Blister Review

Smartwool Merino 250 Base Layer Pattern Crew

After more than a year of testing, the SmartWool Merino 250 Base Layer Pattern Crew has become an all-time favorite. It’s the warmest of the wool layers listed here, but it’s a very comfortable layer for everyday use or as a base layer for lift-accessed skiing and riding.

 

Smartwool Merino 250 Base Layer Pattern 1/4 Zip (Women’s)

Fabric Weight: 250 g/m2
Material: 100% merino wool
MSRP: $110

Julia Van Raalte reviews the Women’s Merino 250 Base Layer Pattern 1/4 Zip for Blister Review

Smartwool Women’s Merino 250 Base Layer Pattern 1/4 Zip

The 1/4-zip women’s version of the layer above.

 

Synthetics

Eddie Bauer Resolution Quantum Short-Sleeve T-Shirt

Material: 100% polyester
MSRP: $60

Luke Koppa reviews the Eddie Bauer Resolution Quantum Short-Sleeve T-Shirt for Blister Gear Review

Eddie Bauer Resolution Quantum Short-Sleeve T-Shirt

The Resolution Quantum uses a unique technology that makes laser-cut perforations on the front and back of the shirt open up when they come into contact with sweat. Though the vents don’t exactly make a night-and-day difference, they do provide a bit of extra breathability, and when combined with the Resolution Quantum’s ultralight construction, they make this shirt our top pick for the hottest days. However, this shirt has no antibacterial treatment, so don’t expect to wear it for more than one run (unless you have no regard for the noses of those around you).

The raw edges of the perforations are also a bit scratchy (though they’re not very noticeable while moving), so we’d recommend the Resolution Quantum specifically for high-output activities in the heat, and not for casual use. It has a slightly slim fit, but is shorter and less clingy than the Resolution Flux (below).

 

Eddie Bauer Resolution Flux Short-Sleeve T-Shirt

Material: 86% nylon, 14% polyester
MSRP: $65

Luke Koppa reviews the Eddie Bauer Resolution Flux Short-Sleeve T-shirt for Blister Gear Review

Eddie Bauer Resolution Flux Short-Sleeve T-shirt

The Resolution Flux’s fabric feels very smooth on skin (rather than the raised texture of most of the wool pieces here), and features seamless mesh panels on the sides, chest, and upper back which add to its breathability. It’s fairly heavy compared to other summer-weight base layers, and that is noticeable. However, the combination of the mesh panels and the main fabric’s very good wicking properties still make this shirt comfortable in warm temperatures.

The Resolution Flux features a Polygiene antimicrobial treatment, which we’ve found to resist odor for about 1-2 sweaty runs. It fits fairly slim through the torso and is pretty long, something that people with shorter torsos might find slightly restrictive.

Luke Koppa reviews the Eddie Bauer Resolution Flux Short-Sleeve T-shirt for Blister Gear Review

Luke Koppa in the Eddie Bauer Resolution Flux Short-Sleeve T-Shirt, Reservoir Ridge, CO.

 

Lululemon Metal Vent Tech Short Sleeve

Material: 51% polyester, 46%nylon, and 3% X-static nylon
MSRP: $68

Luke Koppa reviews the Lulu Lemon Metal Vent Tech Short Sleeve for Blister Gear Review

Lulu Lemon Metal Vent Tech Short Sleeve

The Metal Vent Tech Short Sleeve shirt falls between the two Eddie Bauer pieces in this review when it comes to fabric weight, and it was the best performing synthetic shirt when it came to odor resistance (thanks to the addition of silver fibers).

The Metal Vent Tech Short Sleeve breathes and wicks well, doesn’t feel as clingy as the Eddie Bauer Resolution Flux, and fits a bit looser than both Eddie Bauer pieces. The Metal Vent Tech Short Sleeve is fairly similar in both fabric weight and fit to the Trew Superlight NuYarn Merino Pocket T.

 

Lululemon Swiftly Tech Long Sleeve Crew (Womens’)

Material: Silverescent® fabric
MSRP: $78

Kriston Sinnott reviews the Lululemon Swiftly Tech Long Sleeve Crew for Blister Review

Lululemon Swiftly Tech Long Sleeve Crew (Womens’)

The Swiftly Tech Long Sleeve is a light, comfortable, versatile base layer than can be used for a broad range of outdoor activities, year round.

NEXT: Underwear

2 Comments

  1. alvin baker November 15, 2015 Reply

    Do you (or someone) know of any silk baselayers of sufficient durability for outdoor use? Also, how about something regarding yak wool…I have read some good things about that, but never seen it reviewed by outdoors people.

  2. Blister Member
    Matt October 31, 2017 Reply

    Even as a former industry guy & lifelong gear nerd, g/m2 numbers mean *nothing* to me regarding garment weight or warmth.
    Simply listing the overall weight & size of the garment tested would be a much more helpful starting point: folks at home can easily toss e.g. their favorite zip-T on a postal scale to get a point of reference.
    g/m2 numbers are of no use to anyone who doesn’t work in a fabric mill.

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