Poncho + Insulating Liner System

I have had a love hate relationship with ponchos. Theoretically they make great sense, but I have tried rain ponchos five times for six month or longer. After each poncho experiment I switched back to a rain jacket and a dedicated shelter. This post is about my current re-evaluation of ponchos as rain gear. For a two year period of time I used one of Brawney’s ponchos for both rain gear and as my shelter. I don’t think I will ever return to a poncho as both rain gear and shelter: there are just too many compromises required for little or no weight savings.

Related… I have always thought the US Army Poncho + Liner was an extremely versatile system, but seemed too heavy. I recently realized there are new materials such as Polartec Alpha Direct which could be used to make poncho liner than is significantly lighter while providing a useful amount of insulation. I tested this system at home and used it for walking the Camino Frances with good results.

Why a Poncho?

Drew Smith‘s  The Backpacking Poncho makes a good case for using ponchos.

On the plus side a poncho can be an extremely light and compact item which can provide rain protection for the body, backpack, and can function as a shelter if it is large enough. A poncho made from good material can be a “buy it once for life” item, lasting decades without any maintenance. Another nice feature of a poncho is that it can be put on and then taken off without removing a backpack. You don’t even need to stop walking.

Downsides of ponchos are they can flap in high wind, get snagged when climbing or going cross country, and don’t protect arms when using poles (which I am not), and doesn’t “fit in” (e.g. looks odd) in many urban settings.

The biggest downside for me is that most ponchos are made from non-breathable materials which has no air permeability and zero vapor transmission so moisture often condensates in the chest area. I know people say that ponchos can provide good ventilation but this hasn’t prevent me from overheating and getting wet from condensation even when I hold the poncho up to maximize ventilation. I find ponchos too warm above 55F.

When active in >55F conditions (dry or light rain) I am more comfortable wearing a Shakedry rain shell, or just getting wet provided I have a way to dry myself when either the temperature or my activity level drops.

Motivation for a New Experiment

I realize the conditions I was like the face on the Camino: daytime lows around 40F and nighttime lows sleeping in alburgues around 60F required about the same insulation. This would be a perfect situation to use a poncho liner or wearable quilt for insulation during the day and to sleep at night. The other option would be to sleep in my warmest clothing at night. I discarded the idea of just using clothing because the pants I wear do not provide enough warmth to sleep in.

I considered using ultralight synthetic quilt or a traditional poncho liner, but both options were heavier and more expensive than I desired. Then I thought about using Alpha Direct for the insulation. Unlike many synthetics or down, it doesn’t require a fabric to contain it which reduces weight and allows it to be useful in a wider range of temperatures depending on how much you prevented air circulation. Combining an alpha direct “blanket” with a light weight poncho and sleep sack could provide an extremely light (10.8oz) and versatile system:

Originally I was going to purchase a larger piece of Alpha Direct so it could be the same dimensions as a poncho with a slit to pass my head though.  I ended up using a smaller, unfinished piece of alpha direct because I hadn’t settled on how to attach it to the poncho, and the fabric for a shaped liner would have doubled to cost. Rather, I decided to “make do” with a simple blanket, and if the experiment went well, to make a real poncho liner in the future.

Experience Walking

I ran some simple experiments around the SF Bay Area, slept in our unheated garage and backyard to validate the idea. The first true “field” use was for 31 days walking Camino Santiago – Frances in May 2003. Daytime temperatures were 38F-72F (not counting windchill), sitting outdoors in cafes (~45F-55F), and nighttime sleeping temperatures ranged from 55F-70F. We had several days of rain with the temperature during the rain varying between 45-65F. Right after this trip we were in Taiwan with torrential rains in 65-85F. Winds varied from completely calm to 35mph.

My “base” clothing were Luna sandals, Xoskin toesocks, Patagonia Terrebonne jogging pants, a ArcTeryx Cormac Sun hoody, a PolarBuff, and a Montbell Umbrelo Hat.

When highly active, just my base clothing kept me comfortable when it was >55F (factoring in wind chill), >60F when it was raining. I was wet (except for my head due to my hat), but my movement kept me warm enough, and when the rain stopped my clothing dried in around a hour.

When it was cooler than that some combination of my rain poncho and Alpha Direct blanket gave me just the right amount of insulation. On the coldest mornings (38F air temp, wind, sun not out yet), the combination of my base clothing, my backpack, a Polar Buff, Alpha Direct wrapped over my shoulder and across my front torso, and the Gnu poncho on and snapped shut kept me quite comfortable even when I was just standing around. I particularly enjoyed my arms and hands being comfortably under the poncho without needing mittens.

As it warmed up I would gather the Alpha Direct into a scarf configuration continuing to use the poncho to protect against the wind. Eventually I would remove the poncho and use the Alpha Direct as a shawl, over my shoulders or around my body as a vest which was kept together using magnets made to hold racing bibs on shirts. In modest wind conditions the alpha direct configured as a vest kept me comfortable down to around 40F.

FIXME: Pictures of blanket going from Shawl to Vest using magnets, to Scarf.

A real plus of this system is I could adjust it as I walked. I didn’t have to stop walking and never had to take my backpack off.

One challenge was when the temperature was between 40-50F and the wind was going from 0 to 30mph and the sun was playing hide and seek with the clouds. With no wind and sun strong I wrapped the Alpha Direct blanket around my waist. When the wind was blowing and the sun was blocked by clouds using the Alpha Direct blanket when carefully doubled over my sides and chest was comfortable. The constant reconfiguration was bothersome. In these conditions I tried using the poncho rather than the Alpha Direct blanket. That mostly worked, but sometimes was too warm.

After a couple of weeks I pulled out a Shakedry shell which I brought in case the poncho just didn’t work, and used it as a wind shirt. I continued to use the poncho on especially cold mornings, or when it rained. The next pilgrimage we take I will bring something like the Montbell Ex Wind Shell for those days that are very windy but moderate temperatures.

Experience Sleeping

Night time sleeping condition were primarily indoors with temperatures between 55-75F. When nights were cool, I slept in a pair of shorts and a tee shirt with the alpha direct as a blanket, inside a nylon sleep sack. This was warm enough to sleep well to around 55F. As it warmed up I shifted the alpha direct on top of the sleep sack resulted it less insulation allowing me to sleep in warmer condition. Above 72F I would just use just the sleep sack or no sack with the alpha direct blanket draped over my legs. The sleep sack was a perfect size for colder nights using my relatively small blanket, but I sometimes felt a bit constrained. In the future I think a larger blanket and a larger sleep sack would be more comfortable.

The Gnu Cape

Amazingly light and compact. Could put on / take off over my 23l pack without removing or unsnapping the cape. The cape claims to fit up to a 30l pack. They make a larger version reportedly good for larger packs. I found the shape worked well.

Alpha Direct “Blanket”

The piece of fabric I purchased was listed as 120gsm, model 4004 which doesn’t make sense. 4004 is 90gsm and 4008 is 120gsm. Given the weight & dimensions of my piece, I think I have 90gsm but I am not 100% sure. What I know is that it is an amazing material to use as a poncho liner. Absorbed very little water so would dry amazingly quickly. Didn’t pick up odor after a month of daily use. When air movement was blocked by sleep sack or poncho was quite warm. When doubled up it provided some warmth without wind blocking. (A single layer of 90gsm Alpha Direct seems to hold no warmth in strong winds)

The piece of Alpha Direct I brought was a bit too short. This experiment was successful enough that I will purchase a larger piece of Alpha Direct and actually make a poncho liner rather than just a rectangular piece of fabric. Having a small foot pocket would make it work better in sleeping mode. Open question if the race bib magnets would be strong enough to create a foot pocket.

There was a thread on backpackinglight.com about making a summer sleeping system using alpha direct.

Future Improvements

Make a hoodless poncho which can easily ventilate around my neck. My Montbell Umbrero Rain Hat will keep by head dry and prevent rain from getting in through an open neck area.

Other Options

Ponchos

  • MLD Pro Poncho
  • Sgt Rock  hammock friendly poncho/tarp 
  • No experience, but the  Aricxi Poncho  from AliExpresss looks like a good deal. 
  • The cheapest are typically fragile “emergency” ponchos made from plastic weighing just a couple of ounces. These can be effective in moderate conditions, but they are very easy to tear.
  • The  DriDucks Poncho  is slightly more durable that plastics but is still fragile. It has the benefit of being somewhat breathable. 
  • Vinyl / PVC ponchos which can typically be found as hardware stores. These ponchos are inexpensive and typically weight 8-16oz. They are durable enough to wear, but I won’t recommend using them as a shelter.
  • SaphiRose ponchos with a zipper  have been positively reviewed in the BP gear forum.
  • SMD Gatewood Cape and Liteway Pyraomm which provides rain gear and highly protective shelter. I found them a bit too big to wear, and too small to be ideal shelter but many people love them.

Liners and Wearable Quilts

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