MB Stretch Wind Jacket: H2O-resistance and breathability

Hey Ian,

How is the noise factor with the Stretch Ballistic fabric? Quiet? Compares to…?

Also, how's the sizing for layers?

Thanks for the breathability and water-resistance info. MB couldn't or wouldn't give a CFM number for Stretch Ballistic. In a suck through test, how does the fabric compare to the Houdini's?

Josh,

Noise:
Not a whole lot in my closet to compare it to. It's definitely less noisy than my WT Epic jacket. Maybe on par or a tiny bit quieter than the Houdini. If I had gotten a small instead of a medium, the noise factor wouldn't really be a question. But since I sized for comfort and ventilation and (some) suitability for wearing in public . . . there's room for the wind to whip it around a bit. Haven't really been in the wind yet, so I can't really say for sure.

Sizing:
Seems true to other MB jackets I've owned (only Down Inner stuff), which strikes me as just a bit snug compared to other outdoor gear. I wish I knew my chest measurements, but I'll say that usually I seem to be somewhere between a small and a medium. If outdoor gear base layers are "slim fit," usually a small is too form-fitting for me, and a medium is good; if it's "regular fit" then a small is just fine. Help you out?

So, back to this jacket. I could probably get away with wearing a small but I wouldn't be able to fit much underneath it and it probably wouldn't ventilate too well. So I have a medium, which still gives a pleasing athletic shape due to the (slight) elasticity of the whole piece, but I feel would easily accommodate whichever layers I might be likely to throw under it–probably a base layer and something like the R1, at most.

For comparison, I'll reference a few other pieces people are probably familiar with that I've tried. In general, I would say the MB Stretch Wind Jacket is sized:
– slightly smaller than the Houdini
– slightly smaller than the OR Ion
– maybe equal to the SD Neutron / Isotope (I've tried the Neutron)
– noticeably smaller than the WT Epic Hooded

A lot of this is guesswork, however, because those first three were all items that I've owned in size small, not medium. In a small size, all of those pieces were pretty slim on me, but could at times maybe accommodate a base+powerstretch layer underneath; my guess is that the MB Stretch in size small might not be able to do that . . . at least not on me, comfortably.

My WT Epic Hooded that I currently own is a size medium, so that comparison is easy.

That was a lot, hope I cleared things up rather than muddied them . . .

Breathability
A suck-thru test between the Houdini and MB Stretch are almost equal, with the Houdini possibly having a slight edge. But the point is I can definitely breathe in through the MB without too much difficulty.

I mentioned I haven't tested this piece with exertion in any relevant field conditions. This is still true, but yesterday I did have a helpful experience. I went out to throw the frisbee with some friends and purposefully wore the MB to test how it worked out. Temp was in the 70s with cloud cover and very high humidity–I figured these were basically the top-end conditions that any windshirt would be able to deal with (and while BPing I'd probably not even bother with more than a base in those conditions).

Got to say, the MB performed surprisingly well, given the givens. I am definitely a hot-blooded person, and I expected to need to remove the piece almost immediately once I started throwing . . . but by rolling the sleeves up and unzipping to ventilate, it was a good half-hour before I really needed to take it off to avoid sweating into it. Mind you, I wasn't playing ultimate, but just throwing, which is mild and not strenuous exertion–possibly similar to hiking with a light pack on level ground, I would say.

So the breathability seems promising. Somewhere on here I did note that Don Wilson compared this jacket with the Houdini in terms of breathability–or at least in saying that they are on the same end of the continuum when compared to the whole class.

Ian,
I see you own both the WT Epic hooded and the Houdini. I also own the WT Epic, though the 1/2 zip pullover and not hooded model, and the Houdini. How would you compare the two in regard to wind protection, moisture protection, fit and durability?
I would rate the WT higher all around and better for hiking but prefer the Houdini for trail running (less protection but more breathable). They each will remain a part of my gear closet for now.

I would like to use that Montbell top and bottom as a winter soft shell in place of cloudveil inertia fabric. Thoughts?

Thom,
Actually I got the MB Stretch because I was disappointed with the hood and pocket of the Houdini, disappointed enough that I'm going to get rid of it. That is to say, to answer your questions about the Houdini's field performance . . . I have no idea. Didn't want to muck it up before I tried to return/resell it.

However, from everything that I know through reading, eyeballing and feeling the fabrics, and walking around in a rainstorm with the Epic, I would say you're about right about the characteristics for both.

I'm hopeful that the WT Epic can become my only shell layer for trips that I expect real rain, but I'm not yet sure if it will be breathable enough for that. And then, it might be too baggy. I got a medium instead of a small, and then found that the sizing runs larger than I would have suspected . . . but hey, that could be a good thing. I've found this Epic piece to be nearly as good as a membraned rainshell in terms of water resistance (and of course much better with breathability), so with this sizing, I could throw the Epic on top of whatever else I might be wearing in the event of some really nasty weather.

But eh, anyway Thom, yeah I think you're right on with what you said.

John, good idea. I'm also a big fan of Inertia and very familiar with it as a primary layer (never used it in winter though).

I would say this stuff would do pretty well. If anything, at first glance I would say the MB stretch fabric could be almost as durable, is definitely more wind-resistant, and likely a little more water-resistant. Those last two come at the expense of some breathability, of course, but I've sometimes thought Inertia is, at times, too breathable. The durability thing is just a wild guess on my part since I haven't gotten a chance to use my pieces yet. I'll say–the weave on the MB is definitely tighter than Inertia, but it is also a much lighter fabric. I can't find any weights of the fabric right now but I know that the now-defunct "good" generation of Inertia was lighter than 5oz/yd^2; I'm guessing the MB Stretch Ballistic could be lighter than half that.

So I think it's definitely a viable choice, and possibly a really good one considering that the MB pieces are so stinkin' light.

*Interestingly, it looks like MB might have changed their fabric for this year's Stretch Wind stuff. I have last year's version, which I believe is 50-denier Stretch Ballistic. But on their site, the current version lists "40-denier stretch ripstop nylon." Hmm, interesting. The MB site often doesn't have the right stuff on it . . . I wonder if this is a mistake?

I believe Patagonia designs all their jacket hoods to fit over a climbing helmet which results in a not great fit for a bare head or over a light beanie style cap. I prefer a wind shell for hiking to have a looser fit for layering, like the WT, but for running I prefer a sleeker/trimmer cut.

I typically use a wind shell for its intended application, wind protection, and so I actually prefer a hoodless design (I will just pull on a light beanie for head coverage). I still prefer light rain gear for true protection, something like the Arcteryx Alpha SL at 12 oz., but that's just me.

Thanks a lot for the detailed info about the Stretch Wind. Good to hear that it is quiet.

From your suck tests I guess we can assume it has air permeability in the range of CFM 5-10, which would give it about the best wind-resistance of any stretch woven fabric I'm aware of. I wonder how MB achieved this: it's been my impression that due to the size of stretch-woven threads CFM below 15 was pretty hard to achieve. The 40-50 denier threads in the MB Stretch Wind fabric are fairly robust, no?

One concern I'd have with the fabric, as it was described somewhere as a "twill weave", is that it will be vulnerable to snagging. I was told by a stretch-woven fabric manufacturer that "plain weaves" like schoeller dynamic and tweave durastretch are most resistant to snagging.

But in sum it sounds great: light, stretchy, good balance of breathability and wind resistance, quiet, pretty durable and well cut.