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Insulation under Alpha SV


Original Post
Will Bland · · Halifax, NS · Joined Jun 2017 · Points: 315

I live east coast canada. It's cold and wet. 

I use this for hiking in the cold of winter, walking to and from work early am / in blizzards (I'm a nurse, no snow days).

Typically I wore my Cerium LT + Alpha SV, with a fleece under the Cerium when it got really cold.

The cerium didn't fit well / comfortably, it was too small, so I just sold it. I'm looking for something a bit beefier to replace it. My alpha sv fits with lots of room for layering.

I was thinking of getting a RAB Electron to wear under my Alpha SV /  to replace my Cerium. Does this sound okay? If not - any other suggestions? Possibly a Thorium SV? Although I'd like to stay away from arc teryx puffies after how I found the cerium to fit.


Brian Stewart · · Unknown Hometown · Joined Jun 2017 · Points: 0

Really, that's your call on how the RAB fits. Keep in mind DeadBird's fit is pretty hard to match across brands because of the way they construct the arms of their jackets. OR has a sick puffy called the Incandescent, though they tend to have a long torso cut that might peak out under the Alpha which has the shortest torso cut out of their hardshell collection.

Good luck out there

Will Bland · · Halifax, NS · Joined Jun 2017 · Points: 315
Brian Stewart wrote:

Really, that's your call on how the RAB fits. Keep in mind DeadBird's fit is pretty hard to match across brands because of the way they construct the arms of their jackets. OR has a sick puffy called the Incandescent, though they tend to have a long torso cut that might peak out under the Alpha which has the shortest torso cut out of their hardshell collection.

Good luck out there

Very true. I don't think I'll be able to find a RAB Electron to try on out here. I wonder how the medium fits compared to arc teryx cerium. :(

Kevin Mcbride · · Canmore AB · Joined Jan 2017 · Points: 160

Layer with synthetic, your shell will compress down which causes it to trap less air and be colder. Consider the bd first light, I've climbed ice in -15 just wearing it over a baselayer with no shell and I was warm enough. The electron would work too but as I mentioned down kind of sucks for layering, and the thorium sv would be weird for layering because it's quite a bit longer than the alpha sv.

Will Bland · · Halifax, NS · Joined Jun 2017 · Points: 315
Kevin Mcbride wrote:

Layer with synthetic, your shell will compress down which causes it to trap less air and be colder. Consider the bd first light, I've climbed ice in -15 just wearing it over a baselayer with no shell and I was warm enough. The electron would work too but as I mentioned down kind of sucks for layering, and the thorium sv would be weird for layering because it's quite a bit longer than the alpha sv.


Interesting! Would the Electron be longer as well than my Alpha? Will look into Sythetic!


I think the Electron would definitely be longer in length than my Alpha, unfortunately. Damnit.

Looking into synthetic, the Atom AR is an option. Wish they still made the SV.


GearGuy 316 · · Unknown Hometown · Joined Mar 2017 · Points: 0
Kevin Mcbride wrote:

 the thorium sv would be weird for layering because it's quite a bit longer than the alpha sv.

Agree. 

Thorium AR would be a much better choice and is designed to be a mid layer as oppose to the SV.

GearGuy 316 · · Unknown Hometown · Joined Mar 2017 · Points: 0
Will B wrote:


The cerium didn't fit well / comfortably, it was too small, so I just sold it. I'm looking for something a bit beefier to replace it. My alpha sv fits with lots of room for layering.

Although I'd like to stay away from arc teryx puffies after how I found the cerium to fit.


Why don't you try the Cerium SV?

It is a Regular Fit mid layer, where the LT is Trim Fit, hence feeling too small. 

Since the Cerium SV (and Atom AR) are midlayers, they will fit well under an Alpha SV, without feeling too small since they are both Regular Fit.

I have a few Rab jackets and they layer well under Arc shells except they run longer at the front of Arc shells. But if you don't mind a bit of fabric sticking out at the front of the Alpha SV, then most Rab, OR, Mountain Hardware, BD, Patagonia midlayers are all fine.

Beean · · Canmore, AB · Joined Feb 2014 · Points: 0

You could buy a big puffy non mountain branded jacket for winter oot east. There's knockoff Canada Goose type affairs usually on sale at Winners. Save some bucks. 

Aaron Richardson · · Strathmore AB · Joined Oct 2017 · Points: 0

The or uberlayer Is a great insulation piece, I use mine for everything 

GearGuy 316 · · Unknown Hometown · Joined Mar 2017 · Points: 0
Atvr Atvr wrote:

The or uberlayer Is a great insulation piece, I use mine for everything 

That is one OR piece I have yet to try simply because I have competing Rab Strata Series jackets, and don't need more Polartec Alpha Insulation jackets!

Does your Uberlayer front stick out the bottom front of your Arc hardshell jackets?

Aaron Richardson · · Strathmore AB · Joined Oct 2017 · Points: 0
GearGuy 316 wrote:

That is one OR piece I have yet to try simply because I have competing Rab Strata Series jackets, and don't need more Polartec Alpha Insulation jackets!

Does your Uberlayer front stick out the bottom front of your Arc hardshell jackets?

No mine fits under my alpha ar perfectly 

Jon Frisby · · Colorado Springs, CO · Joined Feb 2013 · Points: 120

I agree that Arc layers fit better under their shells. My nano air is awkward under my Alpha FL, but I suspect this is less an issue since the SV is roomier-cut. I'd avoid Patagonia

Will Bland · · Halifax, NS · Joined Jun 2017 · Points: 315
GearGuy 316 wrote:

Why don't you try the Cerium SV?

It is a Regular Fit mid layer, where the LT is Trim Fit, hence feeling too small. 

Since the Cerium SV (and Atom AR) are midlayers, they will fit well under an Alpha SV, without feeling too small since they are both Regular Fit.

I have a few Rab jackets and they layer well under Arc shells except they run longer at the front of Arc shells. But if you don't mind a bit of fabric sticking out at the front of the Alpha SV, then most Rab, OR, Mountain Hardware, BD, Patagonia midlayers are all fine.

Will check out the cerium SV! 

Thank you! This sounds like the warmest option compared to the atom ar / synthetic.




Guideline #1: Don't be a jerk.

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