Against the glamour of the hardshell waterproof or the insulated belay jacket, the humble windshirt sometimes gets forgotten, but it can be a valuable component in the right clothing system. The Cierzo Shirt is TRC Outdoors’ ultralight, windproof top, designed to be worn over or under any number of layers, or simply stuffed into a pocket until needed.

Imagine cresting a hill on a warm day and feeling the wind cut right through your oh-so-breathable base layer; arriving at the grid reference you arranged to meet a mate an hour early, and knowing he’ll be half an hour late; a trail run on a winter’s morning, with the frosty air sharp in your lungs; an evening in the woods, when you haven’t got the fire quite built yet; a sudden shower on a ‘5% chance of rain’ day, that’ll pass in a minute, but not before soaking your flannel shirt – a fleece, softshell or even a raincoat would likely be overkill, too warm, heavy, or not breathable enough. In these cases, the Cierzo shirt is perfect.

The value of this kind of garment is its simplicity, and the TRC Cierzo shines even against others in the category. The design shaves weight and complexity that comes from zips,  draw-cords or pockets, instead forming a simple pullover with elastic around the waist and wrists to keep things in place. It’s remarkably light (TRC list the regular size as 150g) and comes with a minimal stuff sack, compressing the Cierzo down to a size that will fit in any decent pocket. By folding the Cierzo shirt I found I could get it into the slim cargo pockets on my trousers, keeping it on me as an emergency layer.

As a result of this simplicity, the Cierzo’s shape is a bit weird. TRC make two sizes of their shirt: regular and tall. They recommend the latter for people above 6 feet but at that height myself, I found the regular plenty long enough. Slipping it over my head is quick and easy, and there’s nothing to adjust once it’s on.

The elastic waistband will grip under the arms if given the chance – anyone wearing gear across their chest might face snagging here – but there’s lots of room to fit a range of bodies, without restricting movement at all.

Being fairly slim around the chest and arms, I found the Cierzo downright baggy, though strapping it under the harness of a backpack or my Hill People Gear kit bag brought it under control.

Despite its merits, the simplicity of the cut is a double-edged sword. The loose, lightweight fabric catches the wind and flaps noisily. The hood especially is shapeless and has no means of staying in place. I found myself wishing over and over again for something to secure the hood – a drawstring around the brim, or a strip of velcro across the chin, would do the job – this would of course add bulk and weight, but if these are the only priorities of the Cierzo shirt, I have to wonder why the hood was included at all.

The answer of course is that the Cierzo, like any piece of outdoor clothing, is designed to protect the wearer from the elements. The 30D ripstop fabric does exactly what it should: cutting the harshest parts of wind and sun before they hit the body underneath, without overheating or getting lagged in sweat. 

It keeps off light rain but isn’t waterproof by design, so as to breathe effectively. Areas pressed under gear will get wet but dry very quickly when exposed to the air. TRC’s cut complements this by creating space for heat and moisture to escape around the neck, and the loose arms make it easy to pull the sleeves up to the elbow when further venting is required.

I’ve commented on the Cierzo’s small pack size but in testing, I found myself wearing it constantly when active, over a technical baselayer. In most cases the windshirt was enough to keep my body’s temperature stable, though fitting the Cierzo around other layers was very easy.

It practically disappears under a raincoat or slips easily over an insulating layer, working to protect the delicate fabric of my puffy down jacket from abrasive rockface. As an additional bonus, the ‘earth tone’ of my Cierzo makes for a subtle low profile colourway, reducing the dayglo effect of most commercial mountaineering gear, without the statement of wearing outright camouflage on a leisurely stroll through the hills.