The Rab Cirrus Ultra Hoody is a synthetic insulated jacket that brings an excellent warmth-to-weight ratio to the table. I’ve been using it throughout this autumn, including on hikes in the Lake District and the Scottish Highlands, and it’s been a perfect barrier against not only the cold but also a bit of rain too.
Who Is The Rab Cirrus Ultra Best Suited To
This is a jacket that’s designed with alpine climbing in mind, bringing a low weight, loads of warmth (even when wet), packability and functionality to the table. That’s not to say it’s unsuited to hillwalking or even just day-to-day wear. In fact, this has served me well both as an insulator for Highlands hiking and, more recently, for simply standing in the terraces of the Cardiff Arms Park on a Saturday evening.
From what I’ve seen, it’s warm enough for hillwalking in the UK right through the winter, pairing comfortably with a fleece underneath on the coldest of days.
Performance
The uses PrimaLoft’s new Thermoplume+ insulation which basically involves thousands of tiny clumps of fibres that join together to loft and trap warm air in the same way that down feathers do. PrimaLoft say that they’ve developed the shape of their clusters to make the fill 20% lighter overall, without losing any warmth.
Over the years, lots of companies have been trying to create a synthetic insulation that has the same feel and warmth-to-weight as down. This, in my opinion, is the best I’ve come across so far. It’s super comfortable and very light and packable but it’s also got wet weather performance too, because, unlike down, the fill clusters don’t collapse and lose their insulating properties when they get wet. This therefore is really handy for those days where you need both wet weather protection and insulation. OK it’s not a substitute for a rain jacket, but I found it can see off light rain well and it pairs nicely with a shell layer too.
Then there’s the TILT lining too. TILT stands for Thermoionic lining technology. It’s a reflective lining that enhances warmth by reflecting body heat back toward the user, improving thermal efficiency without adding extra weight or bulk. It works in the same way as one of those space blankets that people use at the end of marathons – only it’s much higher spec! Interestingly, you can actually just about see the TILT’s shiny dots through the translucent liner material.
Fit
I’m 5 foot 10, I have an average build and I tried this in a size medium, which is my usual size. For me, the fit was perfect and I wouldn’t want to size up or down. The hem comes down low enough to cover your backside while I found it didn’t ride up and over a climbing harness or my backpack hipbelt. Likewise, the arms are well articulated and don’t lift the hem up when you’re reaching up for a handhold. I liked the cut too. It’s really comfortable to wear just with a t-shirt and I found there’s enough volume that it can be worn over a thick fleece on those extra cold days.
