There are two schools of thought for making apparel lighter.
The first one, employed by the majority of manufacturers, is to decrease the weight of materials used in the apparel, without sacrificing features. The usual result: a sacrifice in durability (commonly, abrasion and tear resistance) over their more burly older brothers.
The second one, used by far fewer manufacturers, is to decrease features and preserve durability in a very simple garment design. Such is the design philosophy of the Arc’Teryx Sirrus SL jacket.
The Arc’Teryx Sirrus uses a 70 denier, 4.9oz/yd2 (168g/m2), 3-layer Gore-Tex XCR fabric in the high-wear yoke and shoulder areas, and lighter Gore-Tex PacLite III fabric in the rest of the jacket. Even so, the Sirrus weighs only 12.9 oz (366 g), typically about 1 oz (28 g) heavier than the lightest Gore-Tex jackets available today (e.g., GoLite Phantom and Mont-Bell Torrent Flier).
The jacket’s real strength is its durability:weight ratio. It offers a roomy, well-fitting hood equally suited for backpacking and sheltering a small climbing helmet. With a short (harness-friendly) hem, the Arc’Teryx Sirrus SL will find appeal among alpine climbers.
The Arc’Teryx Sirrus SL offers few features: front and rear drawcord adjustments and a stiffened brim on the hood, pit zips, one non-vented napoleon pocket with a water resistant zipper, and a drawcord hem. Lack of other pockets, combined with its trim fit and short cut save significant weight by minimizing fabric used. Further weight is saved through laminated seams with small seam allowances, a narrow storm flap backing the front zipper, narrow die cut hook-and-loop cuff closures, miniature cord locks and fine diameter drawcord. Some weight is gained in the articulated collar design – which allows the hood to function independently of the collar – a nice comfort feature when you have the jacket zipped up and the hood is down.
The $300 price tag isn’t going to win any performance:price contests, especially when compared to more functional (feature-rich), lighter, and less expensive competition from the likes of GoLite and Mont-Bell.
- Style – Hooded Jacket
- Fabric Class – Waterproof breathable – polyurethane laminated PTFE
- Fabric Description – 40 denier 2.5-layer Gore-Tex PacLite III 2.6 oz/yd2 (88 g/m2) and 70 denier 3-layer Gore-Tex 530N XCR 4.9oz/yd2 (168g/m2)
- Breathability Specification – Maximum Ret of 60, ISO 11092 Test
- Claimed Weight – 12.3 oz (349 g)
- Actual Weight – 12.9 oz (366 g) (Men’s Size M as validated on BackpackingLight.com scales)
- MSRP – $300
Graded subjectively on a scale of 1 (lowest) to 5 (highest).
Ventilation Options (3.5)
The Arc’Teryx Sirrus SL provides most of its ventilation via two 16 inch (41 cm) pit-zips, some of the longest we tested. The full front zipper’s dual sliders provide ventilation when a pack belt is worn. Adjustable cuffs and hem round things out, but the trim fit and lack of core vents limits bellows- and chimney venting when the jacket is fully zipped.
The jacket has an articulated collar (a tall, stiffened collar with the hood attached to on the outside of the collar, below its crest). The advantages of such a collar include an better neck seal to retain warmth and more comfort with the hood out of the way when the jacket is zipped up.
A mid-volume hood has a stiffened brim, aperture draw cord with dual single hand cord locks, and a crown draw cord adjusted with a single cord lock at the rear. Hood adjustment allows for a wide range of volume sizing to balance storm protection and ventilation.
Pit zips and the front zipper provide ventilation adjustment with with water-resistant (urethane-coated) zippers and dual sliders. An unvented napoleon pocket with a water resistant zipper is easily accessible by right-handers, but twin torso handwarmer pockets above the belt line would have provided far more utility with little added weight. As is typical with water resistant, non-separating zippers, some effort is required to move the zippers, and one handed operation is not trivial when trying to unzip the jacket from the top.
The hood is large enough for a small climbing helmet but can be adjusted to a well-fitting, low volume hood for maximum storm protection.
The Arc’Teryx Sirrus SL has a trim fit that is very comfortable worn over only a base layer, but enough volume in the sleeves to layer over a fleece jacket. It is inappropriate for layering over anything but the thinnest (e.g., 60g Primaloft PL1) high-loft synthetic jackets or pullovers, because compression of the insulation and binding will occur in the sleeves and shoulders. High loft synthetic vests can be layered under the Sirrus SL successfully.
The jacket is cut a bit short, and thanks to a two-way zipper, does not interfere with a climbing harness or pack waistbelt. The hem comes down to just below the belt in both the front and back. Another inch of hem length would have offered significantly more utility for using the Sirrus SL as a backpacking jacket.
The Arc’Teryx Sirrus SL offers outstanding articulation in the hood and shoulders. More than any jacket we tried, we found the Sirrus SL to move with the body. The hood turned well without binding, even while wearing a pack, and long sleeves and underarm articulation resulted in no wrist exposure or rising of the hem when reaching overhead (alleviating our concerns about the short hem riding too high). The Sirrus’ generously size hood provided has excellent head-turning mobility while wearing a pack. While wearing a fleece jacket underneath the shell, there was no binding in the shoulders when crossing arms across the chest.
Graded subjectively on a scale of 1 (lowest) to 5 (highest).
Storm Resistance (4.0)
The Arc’Teryx Sirrus SL jacket kept us dry in heavy rain. The front zipper is the only place for potential leakage. A water resistant zipper backed by a very small storm flap successfully kept heavy rain out. The single napoleon pocket uses a water resistant zipper, and the pocket is backed by PacLite III fabric. The deep hood with its generous brim and excellent adjustability provided the best precipitation protection of any jacket we tested. It actually kept precipitation, including some wind blown rain, off of our reviewer’s glasses in heavy rain. If you fully open the pit-zips to vent you’re liable to get some water in at your elbows and along your sides – because the pit zips are long! The dual sliders on the pit-zips allow one to partially close them and still vent during heavy rain. The only weakness: the hem is just a hair too short – and bending over will expose a pants hem to rain.
With all zippers and vents closed, the Arc’Teryx Sirrus SL was among the more breathable jackets our reviewers has tested. This is due to the high breathability of the PacLite III fabric used in the body. We hiked uphill at a brisk pace while wearing a pack for an hour at 35 °F (3 °C). By the end, our base layer was fairly damp, but it remained drier than most tests performed while wearing jackets made with polyurethane-based WP/B technologies. At moderate exertion levels, hiking with a 20 lb pack on level ground at 3 mph at 30 °F (-1 °C), we stayed comfortable, with moisture only building up underneath the pack and its shoulder straps.
With its long pit-zips fully open, the Arc’Teryx Sirrus SL performed well in high aerobic activity. We hiked uphill with a pack on for an hour at 40 °F (5 °C). We were breathing hard for much of the hike. At the end, our base layer was damp – but drier than with most polyurethane WP/B jackets we’ve tested. Our reviewer felt the pit-zips cooling and transporting moisture from under the arms and sides. On examining our base layer, we could see the drying effect of the pit-zips. Our front was fairly wet since the pack’s shoulder straps cut off ventilation to the front of the jacket. This is a reason we like vented front pockets in addition to pit zips. At moderate exertion levels, hiking with a 20 lb pack on level ground at 3 mph at 35 °F (3 °C), we stayed very comfortable, with minimal moisture buildup.
With its 4.9oz/yd2 (168g/m2) 3-layer Gore-Tex XCR fabric in the joke and shoulders and 2.6 oz/yd2 (88 g/m2) PacLite III fabric in the rest of the jacket, the Arc’Teryx Sirrus SL is tougher than most jackets we test in this weight range. We subjected the jacket to scraping against rock and bushwacking in thick brush, using it as a sit pad for wet rocks and logs, and the other normal abuses of backpacking and climbing over a several month period. If you need a lightweight shell where durability is the most important feature, you’d be hard pressed to beat the Arc’Teryx Sirrus SL. We gave it this durability grade based on its durability:weight ratio – obviously, there are heavier, more durable jackets out there.
The $300 Arc’Teryx Sirrus SL isn’t going to win any price:performance awards. Although it’s a well-designed jacket, there are lighter, more feature-rich shells out there for a lot less money. Gore branding, the pterodactl logo, and sexy styling is going make the Sirrus SL a winner for some. However, if you climb, or do a lot of bushwacking in foul conditions and need a durable shell, the Sirrus SL gives you the ventilation and durability you need as great weight.
Recommendations for Improvement
We’d love to see dual, mesh-backed torso pockets on the Arc’Teryx Sirrus SL. It would put the jacket’s ventilation and breathability performance among the top of its class.