Patagonia Knifeblade and Northwall Lines: Winter Clothing made from Polartech Powerstretch Pro Fabric

Patagonia Knifeblade Pullover and Northwall Pants

Patagonia Knifeblade Pullover and Northwall Pants at Ouray

Polartech Powerstretch Pro is a new highly breathable and water resistant fabric from the folks at Malden Mills.   Patagonia incorporated it into two different lines of clothing, the Knifeblade and Northwall lines, which are blurring the lines between softshells and hardshells.   The Knifeblade line is uninsulated, and the Northwall line has a light gridded fleece lining.  Knifeblade options are a full zip jacket, half-zip pullover, and pants.  Northwall line options are  jacket and pants.

Grovelling up a chimney in my Knifeblade Pullover. Bird Brain Boulevard, Ouray, CO

I’ve got a Knifeblade pullover, and Knifeblade pants, along with the Northwall pants.  These have become my all-time favorite winter climbing shells.

Here’s why I love them:

The Powerstretch Pro fabric  breathes really really well. When I am working hard, I am a heat inferno. Any hard shell I’ve ever used has never been able to cope with the amount of heat I put out when climbing. This soft shell fabric has no problem dealing with my prodigious heat output.  I sweat less, and stay dry from the inside.

Unlike traditional softshell garments, these pieces are functionally water proof.  They are billed as water resistant, but I’ve climbed in some very wet conditions and stayed dry, including once where I was pretty much stuck under a small waterfall while belaying. I’ve heard of some folks getting some seepage through the seams eventually, but I haven’t gotten wet yet during the winter.  I have used the pants in an extended period of driving rain.  After an hour, the pants leaked and continued leaking.  These are not rain pants, so don’t expect them to stand up to long bouts of heavy rain.  However, for anything I’m doing in winter, they have more than adequate water resistance.

The fabric has a bit of stretch to it.  Just enough to add significant mobility.

The cut of the Knifeblade Pullover is perfect for ice climbing. The pullover style is very clean. Length is long enough that it stays put under a harness. Cut and material make for a good, body hugging fit that doesn’t blouse up and block my vision of my ice screws on my harness, but it has enough stretch and the cut is good enough that it’s not at all restrictive. Hood works very well over a helmet.   Pockets are high and out of the way of my harness.

The pants have articulated knees, and a high waist, coupled with suspenders to keep them up without needing a belt.  Freedom of movement is excellent.  Seat can be dropped via zippers if you’ve got to poo.   The Northwall pants are lightly insulated, which makes them great for really cold days.  The Knifeblade pants are uninsulated, and better suited for more moderate temperatures.

The fabric is very durable. Long chimneying sessions, sharp ice tools and general abuse have not had much effect at all on the Knifeblade Pullover.  I’ve managed to stab some crampon holes in my pants, but the fabric doesn’t rip easily, and the holes were easily repaired with repair tape and seamgrip.

I’ve heard rumors that Patagonia will be discontinuing both the Knifeblade and Northwall lines and won’t have any Powerstretch Pro fabric clothing to replace them.  I hope this is not true.  Just to be on the safe side, I bought spares to make sure I will still have my favorite winter clothes in the event I ever manage to wear out my current ones.


Knifeblade Pullover and Knifeblade Pants, climbing desert ice.


Rab Boreas Pull-On

Rab Boreas in Snowy Conditions

Rab Boreas in Snowy Conditions

The Rab Boreas Pull-On is a strange soft shell.  It’s not very wind resistant.  It’s not very water resistant.  Currently, outdoor clothing companies all seem to be making their softshell clothing more and more weather resistant, blurring the line between hard and soft shells.  The Boreas goes the other direction.  It’s a softshell that provides maximum breathability and minimum weather resistance.  Just based on this description, it sounds useless.  However, it’s become one of my favorite pieces of clothing.

I put out a lot of heat when I’m active.  I’m one of those people who steams in cold weather.  For winter activities, like skinning uphill when backcountry skiing, or moving quickly when climbing or approaching over easy ground, the only insulation I generally require is a midweight or heavy weight base-layer.  However, I typically need a lightweight weather resistant layer over the base-layer to add a little protection from wind and a bit of extra warmth.  Most softshells and windshirts leave me overheated and sweaty.  They just aren’t breathable enough.  They provide too much protection.

The Boreas is just right when worn over a base layer when I’m exerting myself.  It doesn’t cut the wind entirely, but takes the edge off a cold wind and allows the base-layer underneath to continue to function.  Likewise, it won’t keep me dry in sustained rain, but it will fend off snow and light drizzle.

The hood is comfortable, and fits snugly under a helmet.  The single zipper allows for venting, and a chest pocket is large enough to hold sunglasses or a small pocket camera.

So, the Boreas has become my go-to garment for moving fast in the mountains.  As long as I’m moving, it’s just enough.  I stay cool, comfortable, and don’t end up drenched in sweat.  It’s not a great piece for cold weather belaying, or other activities where I’m stopped and inactive for any length of time.  Stop and go sports like hard climbing are not where I use this.  However, for situations where I’m constantly on the move, like backcountry skiing, or easy routes in the mountains where I’m constantly on the move, its’ perfect.

The Boreas fits close.  If you want to wear more than just a baselayer under it, you may want to go up a size.

Weight:  8.6 ounces (size large)

Boreas Pull-On on the Rab Website 

The Boreas Pullover, my go-to top for backcountry skiing.

The Boreas Pullover, my go-to top for backcountry skiing.