Has anyone had any success with wearing synthetics while moving, and at what temperature? I've been considering getting something with synthetic insulation for some winter mountaineering but from personal experiance the breathability and heat may be too great.

Until it's near freezing, I am typically wearing either a base, or a base + windshirt. As it gets colder I will switch the windshirt with something like the rab vapor trail (e.g. softshellism with modest insulation and reasonable breathability). Somewhere between 10-25F I will add a thermawrap vest depending on how hard I am working, how much sun, and how hard the wind is blowing. I find the vest works quite well for me, and lets me dump heat through my arms by pushing up the sleeves. Somewhere below 10F will will layer a thermawrap jacket on depending on conditions and activity level,

As you know, the trick is not to add so much insulation that cases you to sweat. The nice think about fleece is that it's very air permitable, so when combined with an unlined windshirt it makes it easy to tailor warmth. How much insulation people needs varies. My clothing page has a brief charge about how much insulation is required given various activity levels http:/www.verber.com/mark/outdoors/gear/clothing.html#InsulationTorso

--Mark

Edited by verber on 05/07/2008 00:35:03 MDT.

For "regular" hiking: 100 wt fleece over my short sleeved coolmax T-shirt and under my microfiber windshirt works well in temperatures around 40 degrees. At 30 degrees, I add a 200 wt fleece vest, at 20 degrees I use a 200 wt fleece jacket instead of the vest, and at 10 degrees I use both.

When hiking fast or in rugged terrain where I'm generating extra heat, each item generally starts getting used at a temperature about 10 degrees lower than those listed above.

I considered switching to 1.8 osy primaloft sport instead of 200 wt fleece to get a lower pack volume, but someone on this forum said that the nylon inner / outer fabric trapped heat like a sauna compared to fleece. Someone else said that the weight from the pack straps damages primaloft too.

Typically I pretty much do the same as the above: a fleece zip t-neck pullover paired with a Patagonia Hodini windshirt when needed. If I feel I need more insulation then I'll add a Smartwool T, and if it really gets cold then I'll put on my MB thermawrap. The thing to note about this post and the above is that all the layers are thin and light. I avoid the heavier weights of fleece because it then becomes to hard to regulate body heat.

The neat thing about hiking the PNW in fleece I've discovered is that when it's drizzeling and I'm moving at a pretty good clip, the rain seems to evaporate from just body heat, so I seldom resort to rain gear unless it's a downpour.

Too hot for me. I generate a lot of heat once I start walking, so the main insulating top (either a down vest or synthetic jacket) goes into the pack at that point, even in Arctic conditions unless I'm moving around very slowly. When the mercury drops and I need something warmer to wear whilst hiking I'll generally switch to a Buffalo "Pile and Pertex" Mountain Shirt: very warm, wicking, easy to ventilate and exceptionally tough.

Considering how some people ski practically naked... there's no way you can totally prevent overheating when wearing insulation and engaging in high activity at the same time.

I tend to wear my layers when I start off a hike in cold mornings. But I am always careful to start unzipping and eventually peeling the layer off as soon as I stop feeling cold. Sometimes, if you wait till you are "nicely warmed up" -- and/or you keep wanting to hike on "just a bit more" before dealing with the hassle of stopping to take off your pack and peeling off your insulation layer -- you run a real risk of actually soaking your insulation layer before fully realizing!

I am careful about keeping the above from happening, but still prefer synthetic over down insulation "just in case". Synthetics are more forgiving in this sense. But any insulation that provides meaningful warmth when needed will have the potential of overheating you.

Edited by ben2world on 05/07/2008 00:25:18 MDT.

Hi Jonathan,
I use a Patagonia R1 Hoody paired with a Mountain Hardwear Transition vest for snowshoeing in temps down to low 20's. It's easy to vent by unzipping the vest, then the R1 chest zip and pushing the hood off the head. All without removing anything. And snowshoeing generates a lot of heat on our steep Cascades slopes. I also have a windshirt stashed in a hipbelt pocket in case I need to layer up one at rest stops or upon encountering windy conditions(typically when cresting a ridge). For my legs, I use a pair of MH Transition tights with Gore Windstopper over a Patagonia Capilene 1 base layer. I've never overheated or needed to layer up with this combo. Sounds like a fairly close fit with winter mountaineering requirements, which some snowshoeing trips come pretty close to mimicing. Lots of other options out there with similar capabilities, as well.
On the other hand, for temps above ~35 degrees, I switch to a Capilene 1 base under the Transition vest, with the windshirt in reserve for upper body and at around 40 degrees, the Cap 1 base comes off the legs, replaced by Cap 1 boxer shorts. Anything ~50 and above and I'm into 3 season clothing.

Edited by ouzel on 05/06/2008 18:02:17 MDT.

All layers below assume some kind of wind shell over them. I prefer Gore-Tex or eVent when it's very windy or wet or both.

1.BASE LAYER> I like Cabela's Thermastat polyester long johns but others make good stuff, if pricier.

2.LIGHT INSULATING LAYER> light insulating layer (fleece or lighter Thinsulate garments)

3.MIDWEIGHT INSULATING LAYER> for VERY COLD days either add a midweight layer or replace the light insulating layer with this. A vest on top is often enough. A windshell over mid layer or base layer on bottom is usually sufficient. Legs usually don't require as much insulation as the torso & head.
I like my Thermastat jacket and pants for a medium weight insulating layer. (Amazingly warm for all day sedentary treestand sitting for deer hunting when worn over a light insulating layer.)

Keeping the torso MORE insulated than the arms, as with a vest, is often best when moving.

Eric

Edited by Danepacker on 05/06/2008 23:58:46 MDT.

synthetic fill jackets and sweaters are too warm and a do a poor job of moving moisture away from the body, especially while moving. The extra warmth and the shell material of most of the synthetic fill jackets are makes them feel like sweat bucket if used while hiking and backpacking. For mountaineering (depending on what mountain and which time of the year) and for extreme cold weather synthetic or down fill jackets may be more effective.

This is why fleece and wool base and mid layers are much more preferable.

Same basic solution as above. A fleece jacket alone, or that jacket with a wind shell when moving. When stationary I switch to my Montbell Thermawrap.
I have 100 weight and 200 weight to choose from depending on ambient temperature.
The fleece fits under the Thermawrap; but I consider having to use all my layers the sad result of mis-forcasting the low temperature. If I think in advance I would need two synthetic layers I would bring my down jacket instead of the Thermawrap.
Bottom line, I always carry a fleece.
A side effect of having two insulation layers is being able to help out a hiking group member who didn't have enough for the current conditions.

I basically have two systems, one for day hiking and one for backpacking. For day hiking, I carry a fleece sweater and maybe an O2 rain jacket (if there is a chance of rain), a wind shirt (if I think it will be windy on top of a peak) or neither (if it is a really nice day). I find the fleece can handle a very wide range of temperatures and still be comfortable (it breathes well).

For backpacking, I carry a wind shirt, 02 jacket and a puffy jacket. The wind shirt doubles as a bug shirt and is worn when it is too cold to wear nothing over my T-Shirt, but too warm for the puffy jacket. This system doesn't weigh much less than my day hike system, but it can keep me warmer. That allows me to carry a lighter sleeping bag (since I sleep with my jacket on).

I suspected the conclusions reached in this thread 8 years ago, but back then there was a lot of emphasis on "puff" clothing, whether down or synthetic. Assuming hiking and not mountaineering (no peak assaults!), these are the conclusions I've reached:

* You generate a lot of heat while hiking.

* It's easier to regulate heat by regulating hiking pace than constantly taking off/putting on clothing.

* Consider whatever you'd wear in the city, just commuting, in similar temperatures and cut it way back. If you are wearing 100 weight fleece, on the trail you'll just need a midweight base layer. Or, considering the heat trapped by the back of a pack, just a silkweight or lighweight long sleeve crew neck.

* The increments on the trail are almost mico in level. It's often not base layer to 100 wt to 200 wt, sometimes its silkweight short sleeve to long sleeve to zip neck long sleeve to midweight/heavy weight in those categories.

* Once you are dialed into the base layer to wear on that particular day at that particular time, an unlined windshirt is the first "upgrade." One with a full length zipper and hood offers the most flexibility, and the Patagonia Houdini seems to the be gold standard (although the Marmot Ion is a lot cheaper). For example, on an early morning hike out of camp, I'll have on a long sleeve silkweight crewneck for my summer/shoulder hikes, and put on the Houdini zipped up. With the hood up for the first part, then hood down, then unzipped, then off comes the Houdini.

* It's not that much different for a winter hike on a trail (no snow shoes), if I am climbing. Except I'll start with glove liners (real simple, light ones) and a mid-weight zip neck.

* Hiking downhill in winter in the shade, I might add a light "watch cap", which is easy to take on and off.

* Most rain evaporates off from body heat.

* Everything changes in camp. Out comes the Patagonia Micro Pull Pullover (don't need the zipper because I don't hike in it). For sleeping, every extra layer goes on. I carry some fleece layers (vests and/or long sleeve) just in case I have to limp out (not much hiking heat) and could get chilled, and it doubles as way to stay warm in camp and select a lighter sleeping bag.

* I'm not a snow-shoe hiker. I hike open trails in the winter at Yosemite elevations, not slogging through snow at Tuolumne elevations. But everything the posters above said makes sense to me.

* Puff jackets are for mountaineers and base camp, not hiking.

Hi Ben

> Considering how some people ski practically naked... there's no way you can totally prevent overheating when wearing insulation and engaging in high activity at the same time.

Ahem!

LOL!!! :)

Edited by ben2world on 05/07/2008 18:43:19 MDT.

I find them too warm until it gets below well below freezing. The mountaineering "belay jacket" is called that because they accel at keeping you warm while you're standing around.

I carry a Micropuff vest most of the year, but only as a layer for when I stop to rest or for extra insulation at night.

Edited by jbrinkmanboi on 05/08/2008 13:49:02 MDT.