Down vs Synthetic Summer Quilt

[troutalope]

Hey everyone,

I am looking to purchase a 40 or 50 degree quilt and am torn between the Enlightened Equipment Prodigy quilt or an Underground Quilts Flight Jacket. I mainly hike in PA/NJ. I was wondering if anyone had any suggestions or preferences. The Prodigy will be cheaper, the UQ will be lighter. Does anyone know how small the pack size is of the Prodigy is? With the UQ being down I am assuming it will pack smaller as well.

Thanks,
Steven

[egilbe]

For warm weather, I prefer synthetics since there is no weight savings with down at that point. I also wont have to worry as much about keeping a synthetic bag clean. In warm weather, the quilt will need to be more resistant to swear and skn oils.

I have a 30* Prodigy and I just stuff it in the bottom of my trash bag liner in my pack. It doesnt take up much room at all.

[troutalope]

Good points about the summer sweats.

[Typicalsloan]

I have a 40 EE revelation the weight difference is about 5 ounces between the revelation and the prodigy 40. If that plus the comprehensibility of down isn't worth the price difference then synthetic would be the way to go.

[C-shell]

I used an Underground Quilt 20 degree top quilt last year for my hike. Used it for 5 months and it held up great. Because the channels ran horizontal, when it was warmer I was able to shake the down to the sides and it seemed like it was cooler. The quilt still looks like new.

[SWODaddy]

Get a synthetic. I bought an EE 50* prodigy quilt (reg/wide) advertized as being 16.7oz. When it showed up, the tag said 13.98oz which I confirmed on my postage scale. That's only an ounce heavier than the equivalent down quilt. It won't compress as small, but it still gets really small if you need it to.

[SWODaddy]

ETA: My 50* prodigy will compress down to the size of a nalgene, though I never have (nor want) to compress it that much regularly.

[Odd Man Out]

I have a 40 deg Underground Quilts Flight Jacket (wide long) for summer use. Works great. Mine is a couple of years old and has the treated down that is supposed to be less prone to absorbing moisture and losing loft. But they have gone away from that as it may be prone to clumping. I know other makers have also done that. I have not noticed a problem with mine, but then again, loosing a little loft in a 40 degree bag in the summer is not a big problem. Here is the statement from the UGQ web site:

"Their [treated down] benefits are marginal at best in a quilt/sleeping bag, the down will still wet out and you must still take proper precautions to protect your quilt/sleeping bag from the elements. We have also noticed that hydrophobic downs have a tendency to cling and clump causing possible thin spots if the user isn't diligent in lofting their gear. Effective April 11, 2016 hydrophobic down will not longer be offed for sale."

[Just Bill]

Without filling a whole thread...
Roughly 35* is the break point on the down vs synthetic debate on paper. (weights, warmth, value, compression, etc.)

There is also a good technical argument to make that in lower loft (below 1.5") that down is more prone to cold spots versus a good synthetic. A synthetic is a fabric like material, as in it comes in sheets that are a constant thickness. (about 5/8" in 45*) Anyone who has worn a lightweight down jacket versus something like a Patagonia Nano-puff has likely noticed than when you try to use lofts under 1" with down... it gets spread thin to the point of uselessness more often than not.

If you are out in the drier areas out west or in the southwest, humidity is not an issue. But for anyone out for more than a week (or likely to sweat more often in the summer) then synthetic has the better moisture resistance over a week long trip.

As mentioned above- the only real ding (besides a potential few ounces of weight) is compressibility. Over compression damages synthetics. APEX (continuous filament synthetics) tend to be bulky and even more so affected by compression.

So excluding specs...
In a summer bag (35* and up) you will be more likely to encounter moisture, sweat, and a high ambient humidity level that makes it difficult to dry out any bag type- so synthetic has a strong advantage here for most of us.

In summer- overall pack volume is down, so a few liters of pack space lost to lack of compression is not the same issue as in the cooler months when overall colder weather gear is chewing up pack space. So the "drawback" isn't such a big deal.

Much past 30* in an APEX quilt and packed volume and weight becomes an issue.
Even in Primaloft (which can equal or beat a down bag in specs at 45*)- around 20* you face the same issue and down is better.

The exception may be a colder sleeper who might want a 20 or 30* bag even in summer. For them a down summer bag may make sense or at least be a tougher call.

[Just Bill]

I have a 40 deg Underground Quilts Flight Jacket (wide long) for summer use. Works great. Mine is a couple of years old and has the treated down that is supposed to be less prone to absorbing moisture and losing loft. But they have gone away from that as it may be prone to clumping. I know other makers have also done that. I have not noticed a problem with mine, but then again, loosing a little loft in a 40 degree bag in the summer is not a big problem. Here is the statement from the UGQ web site:

"Their [treated down] benefits are marginal at best in a quilt/sleeping bag, the down will still wet out and you must still take proper precautions to protect your quilt/sleeping bag from the elements. We have also noticed that hydrophobic downs have a tendency to cling and clump causing possible thin spots if the user isn't diligent in lofting their gear. Effective April 11, 2016 hydrophobic down will not longer be offed for sale."

Hmm... the list continues to grow.
Can't run them off the top of my head, but the number of good companies either outright discontinuing or no longer automatically filling with treated down is growing. Western Mountaineering never liked it nor adopted it to my knowledge, and Z-packs jumped on and off the wagon a year or two ago as well.

I only bought one batch and made two prototypes with the stuff... but it was very clumpy and turned me off as well. To be fair, some report no issues so it may be an issue with evenly coating each batch rather than a blanket issue. But that said, for a $400 or more bag it's not a chance I'd want to take and unless you used two side by side it'd be hard to find the issue if you weren't making it yourself.

[Venchka]

As always you're on top of things Bill. I read recently that the high end quilt company in Moab (sorry the name escapes me) has resorted to overfilling to get the same temperature rating when using the treated down.
Smoke and mirrors and snake oil. Oh my!
Wayne


Old. Slow. "Smarter than the average bear."

[Wise Old Owl]

Hmm... the list continues to grow.
Can't run them off the top of my head, but the number of good companies either outright discontinuing or no longer automatically filling with treated down is growing. Western Mountaineering never liked it nor adopted it to my knowledge, and Z-packs jumped on and off the wagon a year or two ago as well.

I only bought one batch and made two prototypes with the stuff... but it was very clumpy and turned me off as well. To be fair, some report no issues so it may be an issue with evenly coating each batch rather than a blanket issue. But that said, for a $400 or more bag it's not a chance I'd want to take and unless you used two side by side it'd be hard to find the issue if you weren't making it yourself.

Thanks for the heads up.

[Wise Old Owl]

Hey wait... my "understanding" of what is being done is adding additional electrons that are "sticky" to repel water. So yes they would clump together. The electrons that are added to the surface to the down would attract each other. So I get that part... so if we add more down to reach the the temperature rating, that's fine by me. Why? Down or any insulator will reduce a average air molecule from transferring heat by holding the very air molecules close to the body. By repelling moisture and trapping air overfilling must be a good thing. After that it's a weight issue and real Down wins over synthetic every time...And I take my down in spring and fall, in summer I just sleep on top.

That's my take on the subject.... feel free.

[garlic08]

In my experience, sweat and body oils are not an issue with a quilt, since you don't lie on the quilt. My new quilt stayed clean on its inaugural two-month bike tour, including ten days in a 100F+ heat wave in the humid Midwest, when I'd just pull it over in the cooler pre-dawn hours. A few minutes in the sun once in a while and it even smelled fresh after the trip, and I didn't have to wash it. My wife even said it smelled okay, and that's rare.

I was glad I got the down option for the 30F quilt I got, since I used it down to 30F in the first weeks of the trip, in wet snow in the North Cascades. I like down, have never had a problem with it, and now I kick myself for all the years I used synthetics thinking down would be a problem in wet conditions.

[Vegan Packer]

I just did a few nights at Ricketts Glen (Poconos area) with my Prodigy 50. I tend to be a colder sleeper, so I supplement with a silkweight base layer, and then I add a capilene on top, if needed. Temps got down to 60, and I wore the extra undies and slept comfortably.

The great thing about synthetic is that I wash it (by hand) after every trip, so I always have it like new for the next trip. I would never consider down (I am vegan, after all), but if you are a cold sleeper, you may want to opt to go for the 40 degree version. Other than that, I would absolutely get the Prodigy again.

[Just Bill]

Hey wait... my "understanding" of what is being done is adding additional electrons that are "sticky" to repel water. So yes they would clump together. The electrons that are added to the surface to the down would attract each other. So I get that part... so if we add more down to reach the the temperature rating, that's fine by me. Why? Down or any insulator will reduce a average air molecule from transferring heat by holding the very air molecules close to the body. By repelling moisture and trapping air overfilling must be a good thing. After that it's a weight issue and real Down wins over synthetic every time...And I take my down in spring and fall, in summer I just sleep on top.

That's my take on the subject.... feel free.

That's the part that's not fine by me...
Let's use EE, as they make both synthetic and down so apples to apples is easier-
50* Prodigy (Apex) in regular/regular is 13.94 ounces and $160. http://www.enlightenedequipment.com/prodigy/
50* Revelation(Down) in regular/regular is 10.94 ounces and $225. http://www.enlightenedequipment.com/revelation/

Don't believe that they offer the option as standard, but the bag has 5.2 ounces of fill. Let's buy a spare ounce for $25 for a 20% overstuff to be "safe".
So now you have a $250 UQ at 12oz vs a $160 UQ for 14 oz. Which is a pretty expensive jump to save 2 ounces and a 6x12 packed size vs. a 6.5x12 synthetic.

That's also playing safe with 850 fill versus a more wallet pounding 950 fill.
To be fair, run those numbers at 40* and you are saving about 5 ounces for $100 difference, though saving little pack space.
Run them around 30*... and things look much better for down as Apex in particular adds up fast in weight and bulk.

Now in theory, you have created a 45* down bag with your overstuff, and a 40* would have cost you $245 to start. So you aren't too bad off down to down.

So my take... why pay good money (not necessarily bad money either) for high quality down gear, only to have to compromise what you paid for in weight and dollars by coating the down?

Also... when I can make a Primaloft Gold quilt rated to 45*, weighing under 13.5 ounces, selling for $160 and packing to an easy 5"x12"
That is more water resistant than treated down can ever hope to be.... I do have a slight personal bias against the treated offerings

[Just Bill]

In my experience, sweat and body oils are not an issue with a quilt, since you don't lie on the quilt. My new quilt stayed clean on its inaugural two-month bike tour, including ten days in a 100F+ heat wave in the humid Midwest, when I'd just pull it over in the cooler pre-dawn hours. A few minutes in the sun once in a while and it even smelled fresh after the trip, and I didn't have to wash it. My wife even said it smelled okay, and that's rare.

I was glad I got the down option for the 30F quilt I got, since I used it down to 30F in the first weeks of the trip, in wet snow in the North Cascades. I like down, have never had a problem with it, and now I kick myself for all the years I used synthetics thinking down would be a problem in wet conditions.

Fer me... I tend to agree the down wetting out is not so big an issue overall. Another reason any performance loss in a treated down isn't worth the "benefit".

And fer most... this tends to be a paper issue and not a real world one. Most folks pick up a bag a good 10-20* warmer than they NEED, so there is some real world fluff factor that washes out any lab or paper produced conditions.

If you were chasing specs or limits of gear... the moisture creep is a bigger deal (though mainly below 30*). As you say- a bit of sunshine and highs temps will do wonders for any gear.
In colder temps, over a good week, it is not hard to find a 5-10* loss in warmth in down.
Pepper and Trauma went with a synthetic over down to combat this. Skurka went the VBL route for his cold weather stuff. Even our good pal Tipi Walter notes the issue.
If you are using your 32* bag at 32*...
We've all woken up at 2 am when the temp dipped a few degrees...
and we can tell towards the end of a week that the 32* bag just ain't quite doing it anymore.

All that said...
It's more than a bit of a nerd argument or a gram weenie debate than a real world issue for most.
If you've already followed the standard advice and added 10* to your coldest expected evening, and another 5-10 depending on your "cold sleeping" or ounce counting tendencies or just practical wisdom... you won't notice a 5* loss.

[Odd Man Out]

Now Bill has me thinking I need to replace my quilt. Of course I seem to replace something after every hike. I'm not 100% sure what the specs on my quilt are. I think it is an UG Long Wide 40 deg 800 treated down (may have gotten a little overstuff). But every company's Long and Wide dimensions are different. I think I have used it for about a dozen nights so far without washing (just air out in the sun after each hike). I could weigh and measure it to see how close it might be to a synthetic replacement. If I need a three season quilt I would probably go with the 20 deg untreated down, but for now I am just doing summer hikes. I did a overnight trip last October. The temps unexpectedly plummeted to the 30s and I got rather cold, but I think that was more of a pad issue (Static V) than a quilt problem. I suppose if my current quilt works I should be happy, but dang it's so much fun gear shopping.

[Just Bill]

Now Bill has me thinking I need to replace my quilt. Of course I seem to replace something after every hike. I'm not 100% sure what the specs on my quilt are. I think it is an UG Long Wide 40 deg 800 treated down (may have gotten a little overstuff). But every company's Long and Wide dimensions are different. I think I have used it for about a dozen nights so far without washing (just air out in the sun after each hike). I could weigh and measure it to see how close it might be to a synthetic replacement. If I need a three season quilt I would probably go with the 20 deg untreated down, but for now I am just doing summer hikes. I did a overnight trip last October. The temps unexpectedly plummeted to the 30s and I got rather cold, but I think that was more of a pad issue (Static V) than a quilt problem. I suppose if my current quilt works I should be happy, but dang it's so much fun gear shopping.

I'd blame the pad.
http://thisgearsforyou.com/just-a-quilt-0-1/ There is a temp rating chart on this spec sheet that shows the CLO, Temp, and R-value for the 45* and the 25* bags towards the bottom.
2.5 R is my best mathematical conversion for 45*, and the regular static v is R1.3. The insulated static V is 4.4R, which matches well enough with my calculated 4.86 for 25*.

Granted, one of these days I still have plans to run those number by Yerself and Another Kevin as I'm a carpenter playing at scientist with those formulas.

Though if we look at our good friends at EE. They use a pretty simple system for APEX that bears out in the real world-
CLO of 2,4,6,8 equals temps of 50*,40*,30*,and 20* F respectively.
And Clo to R is a simple conversion of 1CLO= .88R.
So you could say that an R value of- 1.76, 3.52, 5.28 and 7.04 equals 50*, 40*, 30*, and 20* F respectively.
Although the CLO system tends to fumble a bit at the beginning and the end (above 50 and below 20) so it's much messier math when trying to go from carpenter to scientist Specially when you toss in MET's and other factors.

I wouldn't be concerned about currently owning a treated down bag really, especially if it works fine in the field. Some folks report no difference in performance at all. Some observe other issues.

When I make a down bag, it usually takes a few decent pats and a good few shakes to spread and loft all the down after stuffing it.
When I made the two treated samples, I beat the down with a tennis racquet, then put it in the dryer for several hours with tennis balls and still had to break clumps. So call that an extremely bad batch.

Regular down generally gets stuffed in an air-free room or a shower for most MYOG folks- or it ends up everywhere.
The treated down was comically easy to stuff, and was visibly less puffy/wispy in the batch I had.


All that said... we're probably talking 5* difference, maybe 10* on a bad batch. Well within the safety margin for most folks so it's not really an alarming issue. But in future, If I was paying for a premium down (850+) and shooting for the maximum fill power per ounce... it seems counterproductive to add the coating. Although they do say they measure fill power after treatment, so in theory even if a 900 fill coats down to 850 fill- you're still buying the after treated fill weight and paying for an 850 fill.


And while an educated opinion, it's just my opinion and a bit of speculation tainted by a fairly negative experience with one two pound batch of down.
But when a Western Mountaineering never bought in, and other reputable vendors discontinue or recommend against it.
Bottom Line- I'd say there's enough info to skip the treatment on future purchases, but not enough issues to abandon a functioning piece of gear.

[garlic08]

...If you are using your 32* bag at 32*...
We've all woken up at 2 am when the temp dipped a few degrees...
and we can tell towards the end of a week that the 32* bag just ain't quite doing it anymore....

Yeah, I've long noted that down is good for about four nights in those conditions, then you need mechanical (dryer or hotel space heater), chemical (fire), or solar heat to dry things out. Fortunately, for most thru hikers, that four days is about right for town stops, like in the Cascades on the PCT. And more than four days of constant 100% condensing humidity is rare in CONUS hiking. WA state is a notable exception.

Read Ray Jardine's take on synthetic vs down. He's completely in favor of synthetic, as evidenced by what he sells. I've hiked a lot in very similar conditions where he says down failed him, and I remain in favor of down. Go figure.