Base Layer Bottoms

Reviewed by Mike Mineart

The Patagonia Capilene Air Bottoms are Patagonia’s newest base layer design which utilizes a unique seamless knit construction that is composed of 51 percent merino wool and 49 percent Capilene recycled polyester. This results in a very stretchy insulation layer that is both light and warm. The knit construction provides a nice thickness that works extremely well inside of waders for long days fishing in cold streams. Overall this is a great base layer, especially for colder conditions.

Overview The Patagonia Capilene Air Bottoms are Patagonia’s newest base layer design that follows Patagonia’s long tradition of developing new fabrics with improved performance while also trying to find ways to minimize the impact on the environment. The Capilene Air Bottom fabric is a unique a 3-D seamless knit construction that utilize fibers made from 51 percent responsibly sourced merino wool and 49% Capilene recycled polyester.  The resulting bottoms are light, warm and very comfortable to wear.

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Reviewed by LoneStranger

A full-length base layer bottom that has real value on trail in all four seasons. Smartwool's Classic All-Season Merino Base Layer Bottom uses a 150g wool/nylon blend fabric that is heavy enough to add warmth when layered but light enough to use as a hiking tight in warm weather. Comfort and durability for use all year.

  Taft Lodge on the Long Trail (Vermont) Long a fan of Smartwool layers in winter, I spent this summer testing some of their gear that works well in warm weather. Along with the Merino Boxer Brief, which I wore almost every mile of the season, I also spent some time wearing Smartwool's Classic All-Season Merino Base Layer Bottom. Light in the pack and extremely versatile on the body I found these bottoms to be worth carrying on trips long and short. There is also a women's version of this.

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Featured review by Andrew F.

This is a fairly warm synthetic base layer, loose enough to serve as a mid-layer. I recommend wearing alone for cooler weather and beneath a shell or insulated pants in really cold weather. The newer version has two hand pockets rather than a back pocket and is sized even more loosely than past versions—including looser cuffs at the bottom. New ones also have a drawstring, a plus.

The R1 bottom is kind of like a versatile pair of outdoor sweatpants. They are thick enough to wear alone in fairly cool weather if you are active, and they are very warm if you wear them under a shell. On cooler summer nights, I'll often put them on as the temperature drops in camp.     FIT: The fit on these used to be pretty average. They have enough room and plenty of stretchiness to wear over a tight, lightweight base layer or running tights if needed. The current version is sufficiently loose that they wouldn't be a great deep cold base layer, but they now layer better over a base layer bottom.

Read more: Patagonia R1 Pants reviews (2)

Reviewed by Tun

Excellent base layer bottoms.

I was looking for a comfortable pair of base layer bottoms to keep me warm under my work dress pants. These things were perfect. I am about 5'11" 180 lbs with a 33/34 inch waist and I think the medium is a perfect fit. These bottoms are form fitting but not so constricting where it feels too tight or decreases my mobility. The material is very soft to the touch and stretchy. I have read stories about other base layer materials getting ripped by toe nails when people have tried to put them on, but this material has so far been very durable and doesn't seem prone to getting ripped by a toe nail snag.

Read more: Patagonia Capilene 3 Midweight Bottoms review (1)

Reviewed by LoneStranger

The Smartwool Intraknit Merino 250 Thermal Bottom combines 100% Merino wool with an innovative construction that uses 3D modeling to create a warm, comfortable base layer. Made for active use it moves with a body in motion, gentle hiking or hard driven climb alike. Feels pretty good in a winter camp or home on the couch as well.

Smartwool takes a technical leap forward with their newly designed Intraknit Merino 250 Thermal Bottom and I've had the pleasure of extensively testing it over the last five months. Along with their Intraknit Merino 250 Thermal 1/4 Zip, I spent a lot of time wearing this base layer over the Winter. Definitely enough testing to give you a comprehensive look at this updated take on granddad's long johns. Before we dig into the review I thought it might be useful to go over a few basics about wool.

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Reviewed by KiwiKlimber

The Outdoor Research Alpine Onset Bottoms are soft on the skin and easy to maneuver in. They're best when on the move in cool/chilly temps like hiking or bike riding, and they are flexible enough for highly active pursuits.

Conditions and Temperatures:I tested the Alpine Onset baselayer bottoms, along with their crew top counterpart, the Outdoor Research Alpine Onset Crew top. These items are part of Outdoor Research's Alpine Onset collection, which includes an array of men's and women's layers. I’ve worn the OR Alpine Onset Bottoms for five months through the fields and forests of central Pennsylvania while hiking, camping, hunting, mountain biking, and for general everyday purposes. Temps have ranged from -18°F to 60°F (-28°C to 15.5°C), but based on my experiences, these baselayer bottoms are best suited for at or above freezing temps (32°F/0°C or above).

Read more: Outdoor Research Alpine Onset Bottoms review (1)

Reviewed by David Link

Versatile lightweight merino blend layer, perfect for winter backcountry use, chilly nights in camp, and just lounging around at home on cold days.

I’ve been a huge fan of Ibex clothing for many years. The Ibex Indie hoody I bought probably twenty years ago, is still one of my favorites. I was sad when they announced that they were closing a number of years ago and have been pleased to see that they have returned. I was eager to give these bottoms a try. I received the Woolies Tech Bottoms in late spring when our Northern California weather was generally too warm to use them much initially, but with colder and wetter weather descending on us this winter, I’ve been wearing them a lot.  Campground fashion statement rearview Fit and Comfort: The fit of the Woolies Tech Bottoms is as would be expected.

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Reviewed by Jake W

The Fjallraven Bergtagen Long Johns is a base layer pant that utilizes wool in three different weaves to maximize heat retention in key areas (butt, groin) and breathability in others (thighs, calves). It’s a total home run of execution and since I received this base layer for testing I have worn nothing else. It’s exceptionally well tailored, durable, doesn’t stink on multi-day trips, and you’ll have no fear around a fire. The only possible negatives are more inherent to wool, than this product—it takes longer to dry.

PREAMBLE Fjallraven is right up there with Arc'teryx in the confusing naming scheme of their products. The Woolmesh Long Johns is part of their Bergtagen line (Bergtagen is a Swedish word used to describe the feeling of being captivated and humbled by the mountains, awesome name), which includes the base layer (two top options and two bottom options, both men's and women's), mid-layer insulation (two different jackets for both men and women as well as a elephant style sleeping bag), outer shell (pants and jacket, both men's and women's) and a work layer (pants and jacket, both men's and women's).

Read more: Fjallraven Bergtagen Longjohns review (1)

Reviewed by Sean Van Cleve

These high quality, high performance mid-weight base layer bottoms perform without adding unnecessary bulk! Unrestrictive and warm, Ridge’s new base layer line is ideal for people who have an active outdoor lifestyle. Whether skiing, backpacking, or even doing outdoor chores, the merino wool Inversion will help regulate temperature regardless of the conditions!

A winter afternoon walk with Otto SPECS 18.5 micron merino wool 190g weight UPF 50+ 100% recycled polyester waistband Flatlocked seams Fly opening Founded in 2014, Ridge Merino is a relatively new brand to the outdoor industry. Deep savings can be made with this brand because the California-founded company cuts out the "middle-man," and only offers its product line through online sales. Merino wool can be an extremely pricey buy, and this young company is finding a way to get their products into people’s hands! The Inversion bottoms fit great during testing; Size Medium fit perfectly for a 5'10" 155lb build.

Read more: Ridge Merino Inversion Midweight Bottoms review (1)

Reviewed by PhilNC

An excellent base layer choice from a company that understands cold and wet weather. The HH LIFA Merino 2-layer construction keeps you warm and dry in all kinds of conditions, and feels great when wearing it. Watch out for the “athletic” fit when purchasing, but if you get the right fit this base layer will keep you comfortable in rain, sleet, and snow well below freezing.

Note that this is a companion review with the Helly Hansen LIFA Merino 1/2 Zip top.Product Description Helly Hansen (HH) LIFA Merino base layers are designed for cold weather with a two-layer construction consisting of their synthetic LIFA Stay Warm Technology interior and 100% Merino wool exterior.  Their LIFA layer pictured above is designed to push moisture away from the skin while being itch-free and comfortable.  The wool exterior pictured above provides extra warmth and helps wick the moisture away.

Read more: Helly Hansen HH Lifa Merino Pant review (1)