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A New Paradigm for Understanding Garment Warmth
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Dustin Short
(upalachango) - MLife
Re: Chart Vs. Stated CLO Values on 09/07/2011 14:57:03 MDT Print View

Look at the dates. Those charts are nearly 2 and half years old. You'll notice the Patagonia uses Polarguard (PGD) and not primaloft. A lot has changed.

Primaloft recently (within the past year) updated the clo of all their products. Some new manufacturing process is my guess. They actually were rather generous and simply replaced all their old products with the improved products instead of differentiating lines and charging more...

Anyway PL1 used to be rated lower (0.89 if memory serves me). Also remember these are MEASURED clo values. The MB and Patagonia both use sewn through construction which decreases clo. Also manufacturer specs aren't always most accurate, with testing conditions usually being optimized to max out the clo value...

Hope this helps.

hm.. on 10/19/2011 19:51:14 MDT Print View

I don't quite understand... if you look at Richard's other chart and the chart on top, it appears that I will be more than warm if I wear the Fugu jacket and nothing else on a 0 degree while sitting still. Something seems odd... Am I misinterpreting something?

James Klein

Locale: Southeast
Re: hm.. on 10/19/2011 20:17:44 MDT Print View

I didn't dig up the other graph but I am pretty sure I remember the one you are refering to...

The one at the top of this thread gives Iclo (intrensic clo) for various garments. This is the insulation value nominalized for surface area (a 1"X1" square of the jacket would have the same Iclo but much much smaller clo.

The other graph (if I remember) had clo required vs temperature with MET rate traces. The clo required is the total clo of all clothing. If you had the iclo's of all your garments you would have to multiply each by the %body covered and add them together to get clo.

You would need a fugu bodysuit to stay warm at the temperature and activity level.

Link .
(annapurna) - MLife
Re: Re: hm.. on 10/20/2011 12:04:52 MDT Print View

Re: Re: hm.. on 10/21/2011 11:05:34 MDT Print View

Oh, ok... makes sense. I was adding up clo for some of my clothing and it was not adding up to the required clo for the activity level... I forgot about the legs and head...

Richard James
(newparadigm) - F
Re: Ex Light vs. older UL inner on 11/17/2011 01:24:59 MST Print View

Outstanding jacket and good value. It weighs (and packs to) almost nothing and kept me warm on a trip to the Alps with temps in the 20's. Pair this with a lightweight waterproof shell and you probably won't need anything else for most endeavors.

gao qian
(smgao) - F
Re: A New Paradigm for Understanding Garment Warmth on 11/28/2011 05:58:53 MST Print View

hi richard
do you have same parameter about EB MOUNTAIN GUIDE HOODED DOWN JACKET.

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
EB Mountain Guide Jacket on 11/28/2011 07:27:07 MST Print View

4.35 iclo

gao qian
(smgao) - F
Re: EB Mountain Guide Jacket on 11/28/2011 10:11:45 MST Print View

thanks for your quick replay,
this iclo Below my expectations.
so could you tell me the WM vaper and WM meltdown.
the iclo about meltdown is with hood or not?
thanks again

Edited by smgao on 11/28/2011 10:12:30 MST.

Patrick Young
(lightingboy) - F

Locale: Southwest
CLO of Patagonia ultralight jacket/hoody? on 12/10/2011 05:44:17 MST Print View


According to pata cs this series of garments uses the same amount of down as
the down sweater and hoody. Would the clo be the same give that down density
Also is a contributor to that overall value or have they compressed it too much?

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: CLO of Patagonia ultralight jacket/hoody? on 12/10/2011 16:08:36 MST Print View


They test the same. The key to maximizing the warmth of small down channel garmets, like these, is to always wear them under a windshirt or hardshell. This will capture still air pockets over the seams for significant additional warmth.

Patrick Young
(lightingboy) - F

Locale: Southwest
RE: "A New Paradigm for Understanding Garment Warmth" on 01/06/2012 19:51:47 MST Print View

Do you have the clo for the Patagonia ultralight down shirt? I want to layer it with the ultralight down hoody for colder temps.
At what temp would that combo be thermal neutral?

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: RE: "A New Paradigm for Understanding Garment Warmth" on 01/06/2012 23:16:42 MST Print View


The Patagonia UL down shirt is 1.66 Iclo. That shirt plus a MB UL Down Hoody and doing camp chores, sheltered from the wind, will be thermo-neutral at ~31F.

Ismail Faruqi
(ismailfaruqi) - F
CLO on 01/09/2012 19:43:06 MST Print View

Hi Richard,

Could you tell me the lcl clo of following combination:

1) 100% merino 150gsm
2) Capilene 4 half-zip
3) Rab Alpine Pull-on
4) R3 hi-loft
5) Crux Lava (310grams of down)

1) R1 thights
2) Softshell Pant
3) Feathered Friend -40 pants

What is my thermo-neutral point when belaying and doing camp chores? Thanks!

Patrick Young
(lightingboy) - F

Locale: Southwest
RE "A New Paradigm for Understanding Garment Warmth" on 01/30/2012 07:57:58 MST Print View


Do you have a clo on the Golite Bitterroot?


Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Golite Bitterroot Iclo on 01/30/2012 11:24:09 MST Print View


Erik Hall
(telemonster) - F

Locale: pacific northwest
Help me understand on 01/30/2012 15:26:52 MST Print View

I have an old wild things sweater that I want to replace, that has the 2 layers of 60g primaloft 1 quilted together, and the chart gives it a 1.46 iclo. The Rab Xenon, with one layer of 60g primaloft has an iclo of 1.51, and the Rab generator, with 100g of primaloft 1 has an iclo of 2.27. Shouldnt the wild things be similar to the generator, or higher? Thanks

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: Help me understand - Being Politically Correct on 01/30/2012 19:36:54 MST Print View


I have made multiple prior posts explaining that NO synthetic garments that I lab tested, unlike the down garments, were close to their theoretical Iclo specification. I don’t doubt the value of the synthetic insulation’s specified Iclo at the time of manufacture, BUT after being manufactured into a garment and boxed and unboxed during distribution, they test, on average, 51% of their theoretical values. This chart is a portion of one of my many prior posts on this topic from a couple of years ago:


About the same time that I did these tests, BPL was manufacturing synthetic garments for UL backpacking. They were also recommending that synthetic garments and quilts be used during their courses. So, TO BE POLICTIALLY CORRECT, after first posting multiple times that ALL synthetic garments that I tested averaged about ½ of their theoretical Iclo value, I posted all subsequent synthetic garment’s Iclo values based on their theoretical specs. For my personal sustained-wet-weather use, I select garments based on the -51% of Iclo spec. lab test results. I try to not dissuade others from making their decisions based on the manufacturer’s specifications if they choose to do so.

Brett Peugh
(bpeugh) - F - M

Locale: Midwest
Fugu on 03/18/2012 16:55:27 MDT Print View

I wonder if the Fugu is still king of the hill?

I am still trying to figure out how it is that much warmer than my Montbell Alpine jacket. The Fugu is a sewn through construction with less loft and down while the Alpine is box baffled and very puffy. Is it just the metalized inner? Where can I get a jacket just made out of that stuff?

Edited by bpeugh on 03/18/2012 17:09:29 MDT.

/A .
(biointegra) - MLife

Locale: Puget Sound
Re: Fugu on 03/19/2012 11:58:15 MDT Print View

@ Brett - the Fugu has a reflective barrier (think NeoAir with down fill) and an Epic-like fabric which both aid in mitigation of heat loss via radiation and convection respectively. I know of no other down garment that compares. Especially when combined with a well-designed down hood, I still consider it king of lightweight the down-heap. It is hands down the warmest jacket that I own and I only bring it out for sustained winter weather conditions.

See this thread also: wee bpl thread link with opinions, photos + specs of Fugu

Edited by biointegra on 03/19/2012 12:06:27 MDT.