REI Co-op Lightweight Crew Review

The top-half to the well-respected pair of long underwear bottoms, the REI Co-op Lightweight Crew doesn't quite match up when comparing performance. This simple, synthetic top is a blend of 92% polyester and 8% spandex that allows for a more versatile fit, with underarm gussets and raglan sleeves to improve mobility. A UPF 50+ fabric rating is a welcomed addition for summertime use, but a change in fabric construction severely impacts functionality, particularly breathability.

Performance Comparison

Warmth

Likely its greatest asset, the REI Lightweight Crew is not lacking when it comes to warmth. Even though its fabric weight is unavailable, at 6.1 ounces for a size Medium, this top falls squarely on the appropriate end of the spectrum. And yet, it manages to provide a level of heat retention on par with other wool competitors pushing the midweight range. This is remarkable for any synthetic layer — which tends to have trouble competing with the warmth-to-weight ratio of Merino wool in particular — but understandable based on the material design.

Breathability

Even thicker-cut synthetics base layers tend to breathe well, and the Lightweight Crew is no exception. This lightweight top is well suited to summertime adventures — thanks in part to a UPF 50+ protection rating — but tends to handle lower output activities like backpacking better than those that require more exertion. On trail runs, the Lightweight Crew doesn't breathe quite as well as directly comparable synthetic options. While it does a fairly good job of wicking sweat away from your body, the thicker-cut polyester-spandex blend has a bad habit of retaining heat underneath its relative baggy cut.

Comfort and Fit

Just like the matching bottoms, the Lightweight Crew top has a tough time competing head-to-head with the comfort offered by merino wool layers. The 8% spandex adds a welcomed bit of stretch to improve fit, particularly for those with broader shoulders or chests. But despite its silky appearance, this top is more sticky than smooth when worn next to skin.

Raglan-sleeves pull the seams off the shoulders, a thoughtful touch that will certainly appeal to anyone who wears a backpack. Flexible, underarm gussets — combined with the stretchiness of the spandex — will help climbers make that reach for the next hold. And a drop tail hem makes it easier for skiers to keep this layer tucked in to keep the cold out. Yet, despite all of these features, the fit and feel of the Lightweight Crew are simply a bit off.

Drying Speed

This is where the thick cut of this base layer becomes apparent. While most synthetic tops are much quicker to dry than their natural-fiber counterparts, the REI Lightweight Crew is remarkably slow. Our "soak'n'dry" test simulates the process of handwashing and subsequently air-drying these tops — much like you would do on an extended backpacking trip. Despite its weight class, this top took a little more than 65 minutes to fully dry in the mid-day sun of the desert Southwest. To apply some context, that is more than twice the amount of time of comparably weighted synthetic tops, and the same amount of time as a midweight base layer nearly twice the weight of the Lightweight Crew.

Durability

Durability is another particular weakness of this lightweight layer. Based on a similar abrasion test run on the REI Co-op Lightweight Bottoms, we didn't expect any better results out of the Lightweight Crew. Although our laboratory-style abrasion test is overly abusive, the objective data provides us with information that reliably correlates to durability over time. Flatlock seams may help improve the longevity of this top, but it is not nearly as capable of standing up to batterings as well as other, comparably lightweight models.

Layering Ability

As an exposed layer, the material pattern of the Lightweight Crew is susceptible to snags, particularly from thorns that have a habit of catching the thinner pockets that make up the "ventilation" holes. From a perspective of both style and functionality, this top is best considered as a base layer, rather than a stand-alone top. As noted above, the material is less than ideal when worn next to skin — fortunately, this trait seems to fade as the top is broken in through repeated washings. The silk-like polyester slides comfortably under any type of mid-layer, even those built with notoriously sticky Polartec Power Grid fleece.

Value

Don't shy away from our critiques and the relative ranking of this top. Remember, all of the products in this review are scored relative to one another, and that the Lightweight Crew still scores highly in some key categories. It is still a workhorse of a base layer and should receive due credit for its value. At a price point that is significantly lower than the competition, you can purchase a full base layer set — tops and bottoms — for the equivalent price of some other base layer tops.

Conclusion

Simple, functional, and affordable, the REI Co-op Lightweight Crew will not disappoint if you hope to pick up a versatile, 3-season base layer before your next adventure. Solid performance for a very reasonable price, this top offers a respectable balance of warmth, balance, and value.