Wool — Tops
Trew Weightless NuYarn Merino T
Fabric Weight: 105 g/m2
Material: 85% merino wool, 15% nylon
MSRP: $65
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
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.
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
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.
Duckworth Vapor V-Tee and Hoody
Fabric Weight: ~145 g/m2
Material: 38% merino wool, 50% recycled polyester, 12% Modal
MSRP: $65 for V-Tee, $110 for Hoody
Made of Montana-grown wool and recycled polyester, these are a favorite of Blister reviewer, Matt Zia, who says he wears one of them pretty much anytime he’s outside. For slightly colder days or when the sun is shining, we’ll go with the hoody over the t-shirt, and both are durable and don’t smell at the end of the day.
Kari Traa Tikse LS
Fabric Weight: not available
Material: 100% merino wool
MSRP: $75
The ultralight Tikse LS has quickly become one of our staple base layers because of its versatility in all sorts of temperatures. We took the Tikse LS hiking in the beginning of the fall, and are still appreciating the extra boost of warmth under a mid-layer for early morning tours in the winter. The fabric dries quickly in a tent after a sweaty day, and surprisingly did not stink even during a few longer backpacking trips. We’d recommend this product to those with smaller frames because of its stretchy, slim fit. It’s on the lighter end of the spectrum, so those looking for maximum warmth should check out some heavier (200+ g/m2) options. But if you want a versatile year-round layer, the Tikse is an excellent option.
Fabric Weight: 170 g/m2
Material: 89% merino wool / 11% nylon
MSRP: $200
A bit lighter and slimmer than the Mons Royale Supermons, the Norrona Wool One-Piece uses an extremely comfortable wool/nylon fabric that is a bit less insulative than the 190 g/m2 fabric on the Supermons, and this makes the Norrona one-piece a bit better suited for warmer days, or for people that rely more on their mid layers for warmth, rather than their base layers. The hood is tight and works well under a helmet. The only complaint here is the zipper, which has raw edges on the inside that aren’t very comfortable on skin.
Arc’teryx Satoro AR Zip Neck Shirt
Fabric Weight: 180 g/m2
Material: 81% merino wool, 12% nylon, 7% elastane
MSRP: $139
Art’teryx’s Satoro AR Zip mid-weight base layer features a merino / synthetic blend that helps it resist odor like a merino piece, while the synthetic element should help with durability. We’ve been impressed with the Satoro — it’s surprisingly warm given its 180 g/m2 fabric, and has yet to show any signs of wear after a lot of hard use. The slim fit and elastic properties make it very comfortable, the cuffs resist stretching out, and the small chest pocket is perfect for accessories.
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.
Mons Royale Cornice Rollover LS (Women’s)
Weight: 190 g/m2
Material: 100% merino wool
MSRP: $130
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.
Mons Royale Yotei Powder Hood
Fabric Weight: 190 g/m2
Material: 100% merino wool
MSRP: $120
The Yotei is a favorite piece around here, and we’ve found it to be a highly functional and comfortable base layer that features a looser, longer fit compared to the Checklist Hood. The Yotei’s hood easily fits under a helmet, and it comes up high enough in front to serve as a buff. Comfortable, functional, and it looks good on and off the mountain.
Mons Royale Supermons ¾ One-Piece
Fabric Weight: 190 g/m2
Material: 100% merino wool
MSRP: $200
Mons Royale calls the Supermons the “stripped down, race-car version” of their Monsie one-piece. Compared to the Monsie, the Supermons is slimmer, has a ¾ length boot-top cut, no hood, and features a more breathable merino mesh fabric on the back. If you’re looking for a ski-specific wool base layer, and appreciate the benefits of a one piece, the SuperMons is a great option.
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
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.
Kora Shola 230 Crew
Fabric Weight: 230 g/m2
Material: Himalayan yak wool
MSRP: $145
Unlike nearly all of the other wool pieces here, the Kora garments are not made with merino wool. Instead, they use the wool from Himalayan yaks. Kora claims that yak wool is warmer and more breathable than merino, while being just as soft.
In use, I have found that the Kora yak wool does breathe very well and is quite warm (potentially more so than the equivalent 230 g/m2 merino fabric).
However, the Kora pieces do have some downfalls. First, they don’t offer anything lighter than 230 g/m2 as of right now, and I think many people will find it to be too warm for year-round use, and maybe even for late-season skiing. And second, I do not think the yak wool is as soft as any merino wool I’ve used. It’s still pretty comfortable and far softer than your old lambswool sweater, but if maximum softness is your priority, I’d go with a merino piece.
But if you’re not sensitive to wool and want a very breathable, warm, and odor-resistant layer, the Kora lineup is worth a look.
WoolX Switchback Hoodie
Fabric Weight: 230 g/m2
Material: 100% merino wool
MSRP: $99
This wool hoodie is a great option if you want something that you can use as a base layer one day, and then just while lounging around the house or hanging with friends the next day. It’s loose enough to not look weird while wearing it out, but its super-soft merino fabric also breathes really well and resists odor for days. And at 230 g/m2, the Switchback is quite warm.
If you want slim-fitting layers that don’t take up much room under your other layers, I’d check out the Mons Royale Yotei Powder Hood instead. But if you want something a bit looser, the Switchback Hoodie is a really comfortable piece that performs as well as any other merino piece while also coming in at a nice price.
Smartwool Merino 250 Base Layer Pattern Crew
Fabric Weight: 250 g/m2
Material: 100% merino wool
MSRP: $100
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
The 1/4-zip women’s version of the layer above.
Icebreaker Tech Top Long Sleeve Half Zip
Fabric Weight: 260 g/m2
Material: 100% merino wool
MSRP: $120
This piece is very soft, and one of the warmest merino wool base layers here. The fit is slim without being restrictive, the arms are plenty long, and the zip neck gives you some ventilation options. If you’re looking for a very warm merino base layer, the Tech Top is worth a look.
Wool — Bottoms
Mons Royale Double Barrel Legging
Fabric Weight: 190 g/m2
Material: 100% merino wool
MSRP: $100
Using the same soft, midweight merino wool fabric as the Mons Royale 1962 Henley, the Double Barrel Long John is a very comfortable and versatile legging. If you get along well with the full-length legs and lack of a fly, this piece is great for most cool-to-cold weather activities. The extra-wide waistband is also a nice touch that keeps the legging in one place, and does so without any hot spots.
Mons Royale Alagna ¾ Legging
Fabric Weight: 190 g/m2
Material: 100% merino wool
MSRP: $80
These leggings use the same fabric as the Double Barrel Long Johns, and are another really soft and comfortable lightweight merino wool layer, and the ¾ length sits right above ski boots without bunching up. For reference, the men’s version is called the Shaun-Off ¾ Long John FOLO.
Fabric Weight: 200 g/m2
Material: 100% merino wool
MSRP: $80
Soft, breathable, odor resistant, and with the perfect cut for ski boots, these merino bottoms work great for skiing / snowboarding, and are slightly warmer than the Mons Royale Alagna ¾ Leggings.
WoolX Backcountry Mid-Weight Base Layer Bottoms With Fly
Fabric Weight: 230 g/m2
Material: 100% merino wool
MSRP: $79
Just like the other WoolX products, these bottoms are super soft, breathable, warm, and odor-resistant. They’re one of the warmest wool bottoms here, and are a great option for cold days, as long as you don’t mind rolling them up above your boots.
Kora Shola 230 ¾ Leggings
Fabric Weight: 230 g/m2
Material: Himalayan yak wool
MSRP: $135
These leggings use the same yak-wool fabric as the Shola 230 crew, and are also very warm, quite breathable, but not as soft as the merino wool options. So, it’s the same story as the Shola Crew — if you don’t have sensitive skin, then these are a great pair of leggings that work really well for most of the ski / snowboard season, especially on very cold days.
NEXT: Synthetic Tops and Bottoms
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.
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.
I disagree, most merino wool baselayers have it listed, so after you own one or two, you get a pretty good idea for what you like. It’s not the be all-end all about fabric type, but it’s better than nothing.
I know that I prefer merino under 200g/m2, since its dries fast and isn’t too warm. But it’s not durable. 260g/m2 is getting pretty darn heavy for a baselayer, and in wool, will really impact dry time. Ok for resort skiing, but to warm for summer use, or active sports for me.
Hi guys. Thanx for such list. Could you please compare warmth of Trew NuYarn shirts and Mons Royale shirts? NuYarn site says that it’s fabrics 25% warmer. So their 145gms base layer must be indentical in warmth with 180-190 gsm.
All the problems with “stink” are easily fixed by simply putting some cologne on before you go out and play . I learned this from a friend, it works really well, and frankly everyone should be doing this, even if they use wool. Correct me if i am wrong, but cologne was originally invented to cover up the stink from pre-enlightenment Europeans who bathed once a year because bathing was frowned upon by the church (it encouraged sexual promiscuity). If it worked for them it will work for you.
Silk is awesome but it is so $$$. I have some silk glove liners and they are amazing.