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Alpine Houdini
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Sean Passanisi
(passanis) - MLife
Alpine Houdini on 01/03/2014 09:57:06 MST Print View

I see that Patagonia now shows availability of the new Alpine Houdini featuring a "highly water-resistant woven nylon shell, with laminate membrane and DWR finish [that] holds a 10,000 mm water column."

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Spring 2014 Alpine Houdini & An Easy Way to Find Good Alternatives on 01/03/2014 12:28:21 MST Print View


Thank you for your post. After reading it, I chatted with Patagonia CS (Lupe) in an attempt to understand how Patagonia is positioning this 2014 Houdini Alpine which they call a "jacket". He said the Spring 2014 Houdini was using the same material and coating as they used in the Spring 2013 Houdini version. The Spring 2014 Houdini Alpine is a different product type.

Their latest (Spring 2014) Alpine Houdini description defines the construction as having a laminate membrane with a 10,000 mm H2O HH. I tested their only prior Spring 2013 Houdini version and it did not have laminate membrane. It further differed from the 2014 Spring Alpine Houdini version in that I tested 474 mm H2O HH with an associated air permeability of 3.73 CFM. I have previously tested the Houdini versions for all prior years and they average a HH of 141 mm H2O with an associated 35.8 CFM air permeability. The 2013 and 2014 Houdini versions are both the same with 3.73 CFM air permeability. The 2014 Alpine Houdini is another different class of product.

35 CFM is the optimal windshirt air permeability for sustained average 7 MET (UL backpacking) activities when sometimes you skin temp is too warm and sometimes too cold. 7 MET is the highest average exertion rate that can be sustained indefinitely.

The scientific explanation for this 35 CFM optimal value has to do with the measurement of the individual fabric layer resistances and air gap resistances in a base layer plus windshirt combination. The combined moisture vapor transport resistances are reduced as the windshirt breathability progressively goes up to ~35 CFM and then it plateaus. Contrary to intuition, a 70CFM windshirt provides about the same clothing system internal water vapor moisture resistance as a 35 CFM windshirt.

I invented a $.01 windshirt tester (paper coffee filter air permeability reference) that is MUCH more accurate than just blowing through fabric to determine if it is easy or hard. For those who believe in science, a double layer paper coffee filter will provide the near optimal 35 CFM air permeability to compare windshirt fabrics. For those who prefer intuition (more breathability is always a good thing), a single layer paper coffee filter will provide ~70 CFM.

Edited by richard295 on 01/03/2014 18:56:20 MST.

Stephen Komae
(skomae) - MLife

Locale: northeastern US
Houdini vs. Alpine Houdini on 01/03/2014 12:37:38 MST Print View

To my knowledge the Alpine Houdini (2014) does not replace the Houdini. It is simply a divergent line.

The Alpine Houdini is meant to be ultralight rain and wind protection for climbers.

The Houdini is meant to be ultralight wind protection for runners, with the side effect that it deals with rain pretty well temporarily.

I do wish the Houdini went back to its 2012 iteration, but I have been using the 2013 version with plenty satisfaction.

That said, the Westcomb Crest Hoody is a pretty suitable alternative with Pertex Equilibrium, which is quite water resistant, very breathable and has mild stretch. It loses out on the Houdini with abrasion resistance, but for backpacking it is not a big deal.

I could see the Alpine Houdini as being a rain jacket replacement for those who want good protection when it is necessary but rarely encounter heavy downpours.

Dale Wambaugh
(dwambaugh) - MLife

Locale: Pacific Northwest
Re: Houdini vs. Alpine Houdini on 01/03/2014 13:07:28 MST Print View

The Alpine Houdini is a rain jacket in my estimation: taped seam and a laminate membrane = rain jacket.

The Light and Variable Hoody looks like a tougher Houdini with hand pockets and 7.2oz weight.

Woubeir (from Europe)
(Woubeir) - F - MLife
Re: Houdini vs. Alpine Houdini on 01/03/2014 13:08:28 MST Print View

Well, I thought that too, but now I notice there's no 'regular' Houdini for Spring 14.

Adam Kramer
(rbeard) - F

Locale: ATL, Southern Appalachia
thanks richard on 01/03/2014 13:23:22 MST Print View

good stuff as always

Paul Hatfield
(clear_blue_skies) - F
35 CFM on 01/03/2014 14:17:46 MST Print View

Which brand/models of windshirts have 35 CFM or greater air permeability?

(What is the permeability of Pertex Equilibrium? It's not listed on the Pertex web site.)

I know the topic of breathable windshirts keeps coming up in the forums. Perhaps this kind of information could be consolidated into a wiki so people who are looking for a breathable windwshirt could just refer to the wiki and know exactly which windshirts have high permeability.

Woubeir (from Europe)
(Woubeir) - F - MLife
Re: Re: Houdini vs. Alpine Houdini on 01/03/2014 14:18:04 MST Print View

Wait, here it is:

eric chan
(bearbreeder) - F
helium on 01/03/2014 14:33:23 MST Print View

sounds just like an OR helium

now the real question is whether its much more "breathable" than one


Brian Johns

Locale: NorCal
Houdini vs. Alpine Houdini on 01/03/2014 14:34:20 MST Print View

These look totally different. On the patty site, they have the Alpine Houdini at 6.6 oz. and $200, the traditional Houdini is still listed at $99 and 4.0 oz. Seems like a confusing naming convention to me. And products with a more similar name than use or construction, not to mention weight.

Delmar O'Donnell

Locale: Between Jacinto & Gorgonio
Spirometer Calibration on 01/03/2014 17:44:05 MST Print View

> I invented a $.01 windshirt tester (paper coffee filter air permeability reference) that is MUCH more accurate than just blowing through fabric to determine if it is easy or hard....a double layer paper coffee filter will provide the near optimal 35 CFM air permeability...a single layer paper coffee filter will provide ~70 CFM.

Thank goodness...never liked the Vader test, too much variability for my taste. (Not to mention the *actual* taste of new jackets, and the withering looks I get from staff as I breath-test jackets at REI).

Someone here at BPL had the idea of using a spirometer (lung capacity tester) as the dependent variable for a home permeability tester. I already own one, along with an air compressor that can yield a constant, repeatable amount of air-- so would like to try it. But I don't have swatches of fabric of known permeability, so my ability to calibrate has always been missing.

If I'm reading Richard correctly, he just solved my calibration problem. One coffee filter 70 CFM, two 35, and by extrapolation three 18, and four, 9 CFM. Yes?

EDIT: Sorry for the thread derail, I'll open a new thread for this. Please carry on re Patagonia.

Edited by Bolster on 01/03/2014 18:03:30 MST.

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Spirometer Calibration Using NisCofFil? on 01/03/2014 18:36:51 MST Print View



I did a Google Shopping search to determine what brand of coffee filter was most commonly listed; it was Bunn. I ordered some Bunn filters to test in addition to the Trader Joe house brand filters I normally use to make coffee. My lab test results were as follows:

Bunn single layer = 72.85 CFM
Bunn double layer = 38.37 CFM
Trader Joe single layer = 64.68 CFM
Trader Joe double layer = 27.47 CFM
Average double layer = 32.92 CFM

From my limited testing, I concluded that any coffee filter should be adequate for the BPL forum members to APPROXIMATE mouth-air-pressure-air-permeability as: 1-Sub 35 CFM, 2-Approximately 35 CFM, 3-Between 35 and 75 CFM, 4-Approximately 75 CFM, and 5-Greather than 75 CFM.

I will leave it to someone with a spirometer to determine if they find a coffee filter useful for its CRUDE calibration.

Delmar O'Donnell

Locale: Between Jacinto & Gorgonio
Estimating CFM on 01/03/2014 19:20:28 MST Print View

Excellent Richard! Thanks!

I've started a new thread on this topic, so as not to swipe this thread from the Houdinites: "Estimating CFM Breathability with a Spirometer in the Store."

Delmar O'Donnell

Locale: Between Jacinto & Gorgonio
Interesting from Patagonia re CFM: "No Higher than 15 CFM for Shells." on 01/04/2014 20:19:01 MST Print View

From "Patagonia's response to some questions about materials and testing."

"We've found that fabrics that measure as much as 5 CFM are still functionally windproof: that is, you don't feel the breeze come through. And they afford much greater comfort on the uphill. So we use 1-5 CFM as our standard for weather-protective soft shells (Mixmaster, Dimension, Dragonfly, etc.)

Shells for higher exertion activities (e.g. Slingshot, Super Guide Pants, Talus Pants) must be even more breathable. For these products we hold to a comfortably wind-resistant, but not windproof, standard of 10-15 CFM.

Beyond this, we don't go. We don't produce shell fabrics with a higher CFM (say, 15-20) because our field test shows that further gains in breathability don't offset the heat loss from wind penetration. "

Ryan Smith
(ViolentGreen) - F

Locale: Southeast
Re: Interesting from Patagonia re CFM: "No Higher than 15 CFM for Shells." on 01/04/2014 20:29:44 MST Print View

Interesting. I suppose hikers are OK with a little more heat loss created by higher CFM apparel since we are generating a lot of heat while moving. I would agree with their claim if 1-5 CFM being completely windproof. I know those CFM's don't pass the Darth Vader test.


Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: Interesting from Patagonia re CFM: "No Higher than 15 CFM for Shells." on 01/04/2014 20:50:34 MST Print View


It could have been FUD and obfuscation to thwart competition or a change in plans. That marketing presentation is more than 8 years old and their competitors were marketing Polartec Wind Pro (since 1999) while touting the benefits of its 60 CFM air permeability. Prior to adding coating to the 2008 and later Arcteryx Squamish wind shirts they were approximately 100 CFM.

That Patagonia marketing presentation is probably new to you but, it was created sometime BEFORE it was originally posted to these forums on 02/03/2005 by Colin Thomas. Mark Verber subsequently added the information to his Web site.

The BPL staff editor which has focused the most on field testing windshirts is Dave Chenault; his most recently rated number one windshirt has 80 CFM (Rab Boreas). Do you think that he agrees with that old marketing presentation? Do you?

Edited by richard295 on 01/04/2014 21:20:58 MST.

Delmar O'Donnell

Locale: Between Jacinto & Gorgonio
Freshman on 01/04/2014 22:08:52 MST Print View

By analogy, Richard, you are a professor, and I am a freshman. I don't even have an opinion. But I am one of those freshmen who sits in the front of the class, takes copious notes, and would be very interested to hear what Dave says.

It didn't escape my attention that the pre-2013 Houdini was considered to be quite breathable at 35, which in itself contradicts the Patagonia quote.

Edited by Bolster on 01/04/2014 22:25:53 MST.

Oliver Nissen
(olivernissen) - MLife

Locale: Yorkshire Dales
Re: 35 CFM on 01/19/2014 07:10:19 MST Print View

"What is the permeability of Pertex Equilibrium?"

Which one?

There are many different variants (and thus save confusion, none get listed on Pertex's website.) Years ago I worked at Equip Outdoor Tech' (Rab) and vaguely recall the manufacturer's stated ratings varying across the product line between something like 5CFM and around 20CFM - but I can't recall under which test standard/protocol. Pertex is something of a "walled garden" nowadays, so I don't get a look in at their fabric range at trade shows nowadays.

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: Re: Interesting from Patagonia re CFM: "No Higher than 15 CFM for Shells." on 01/31/2014 09:49:13 MST Print View

Patagonia's Nano-Air Jacket and hoody alternative to Polartec Alpha information was reported by Will R. here:

If you zoom on the Patagonia Nano-Air Jacket and Hoody chart performance chart, they list its CFM value as 45.

They state, "..The Patagonia Nano-Air Jacket and Hoody combine a Toray synthetic insulation and Patagonia 4-way stretch shell to yield exceptional softness, stretchiness and breathability unmatched by competitor’s products, which presumably includes Polartec Alpha insulation. The chart to the right provides results from Patagonia’s lab tests, which are certainly attention-getting. This is a garment intended for active cold weather pursuits, WHERE YOU WANT MOISTURE TO BE READILY EXHASUTED rather than trapped inside...


Will R. also reported, "Patagonia will also update their popular Houdini Pullover windshirt for fall 2014 with a great new fabric with DWR. Weight is 3.1 ounces and MSRP is $89." It will be interesting to see WHAT AIR PERMEABILITY they provide.

Edited by richard295 on 01/31/2014 10:04:15 MST.

Babak Sakaki
(persianpunisher) - F
^new houdini is like the older one on 01/31/2014 15:35:43 MST Print View

Newer houdini will be more breathable, from what I was told.