Columbia Mid-weight Omni Heat Thermals

I am sitting on a rocky ledge with my feet hanging over 4,000+ feet of air. The sky is fading from black to purple to peach and red. It is five degrees and my face is numb but the rest of me is warm thanks to my Columbia Baselayer Midweight Top and Bottoms. Columbia’s thermals have become my favorite article of clothing to wear on all of my trips. I have worn them everywhere from the tops of snow-doused mountains, to rock climbing in the desert, through ice encrusted forests, and even to the grocery store. There are four main features that I really like about the Columbia Midweight Baselayers: the Omni-Heat technology, the half-zip on the thermal tops, the thumb holes, and the breathability.

Columbia claims that their thermals are 20% warmer than the competition and while I cannot determine a 20% difference I can definitely tell that they are warm. The main contribution to the warmth factor of these thermals is the Omni-Heat technology. The idea behind Omni-Heat is to recycle your body heat. Columbia does this by applying a thin layer of silver material inside the thermals that reflects the heat back towards your body instead of letting it “escape” through the fabric like other lesser thermals. This reflective insulation has the highest heat retention per gram of synthetic insulation in the industry (according to Columbia). One small problem I encountered with the reflective lining was that it was a bit itchy at first. However, after the first washing the fabric softened up significantly and the itching went away.

The zipper on the thermal tops is another great feature. I have never owned a pair of thermals with half zip; I used to think it was a gimmick but now I will never go back to thermals without a zipper. I have a very large head and getting tight-fitting base layers on over my large melon can be quite difficult and sometimes impossible – but not so with these thermals. The zipper also serves another function in that it regulates my body temperature. I can either zip it all the way up or down depending on the conditions. One issue I had is that my men’s thermal bottoms have no fly whatsoever. However, Columbia does offer another model with a zippered fly that costs the same as the thermals without any fly.  Next time I will definitely get the thermals with a zippered fly, as it is a bit difficult to conduct mid-hike reliefs, especially when wearing gloves.

Another nice touch is the thumb holes, which are great when the temperatures drop and you are wearing heavy gloves. This keeps your wrists warm while you are moving as the shirt cannot slide up your arms. I appreciated this particular feature when I was taking my gloves on and off to put on crampons, take a photo, or dig some food out of my pack as I did not have to keep pulling my thermals back down. A small inconvenience for sure but a much appreciated feature that I think all base layers and soft shells should come with.

Last but not least and probably the most important function of a base layer is its breathability and Columbia’s Midweight Baselayers do not disappoint. They do a great job at wicking away moisture and keeping me dry even under several layers. I have worn them layered under down jackets, rain jackets, and mountaineering bibs and they always keep my dry and comfortable. I do develop wet spots under my pack but they dry quickly, usually within a minute or two once I remove my pack.

Columbia’s thermals have become my go-to clothing for all of my hikes. They hardly take up any room and even if I know it will be warm I throw a set into my pack just in case. They are competitively priced and definitely worth a look if you are in the market for a new set of thermals.

Photo Courtesy of Columbia


*  Warm

*  Thumb holes to keep them from sliding up your arm when layering

*  Omni Heat

*  Zippered chest


*  A little itchy right out of the container

*  No built-in fly in the bottoms

*  Cuffs are a little tight – it can be hard to get your hands through if you have a watch on.

Technical Data

Manufacturer: Columbia

Date available: Currently on the market

Manufacturer’s Website: Columbia Omni Heat

MSRP: US$ $60 Top $55 Bottom

Listed Weight:

Actual Weight:

Materials: 86% polyester/14% elastane

Size/Model tested: Medium

Warranty info:

Colors Available: Black, Grill, Intense Red, and Compass Blue (Tops only) Black (Bottoms only)

©Isaac Tait

Leave a Reply