Open main menu

Down vs Synthetic

I know there are quite a few opinions out there etc and articles on this but I figured I would get opinions from some of you. I am looking for a 3 season bag that is 20 or lower but relatively light since I just found out my brother took my last bag. 

Looking for your opinion and personal experiences with a down or a synthetic and which you would choose. Also any bag recommendations are useful as well I am looking in the gear reviews as well. Mostly just a bag that can withstand summer months or a bit of spring or fall. 

Thanks for the help

I would ho with down personally, i just love its soft lofty goodbess. For 3 season use you have tons of options. Have you thought about a quilt? A quilt is well suited to 3 season use, much lighter than a bag, and cheaper. I personally prefer quilts from

If you want a bag, I would go with the best quality you can afford, whithout a budget set forth i would say WM or FF.

I'll second the down and the quilts.   My three season quilt is only a 40°f but I've used it down to around 20°f while wearing my puffy and been pretty cozy.  It is a discontinued TRest Ventra.  I haven't had my hands on their newer models, but the design of the Ventra was spot on with nice foot box and side curtains.

Hi Mike,

My answer depends entirely on where you go outside and what you do there. For "fast and light" alpine ascents in Colorado, California or other states with relatively infrequent rain and low-humidity, down is an established favorite. AT hikers like me, used to the humid east coast, often prefer synthetic fills because they retain loft when wet, and require less care.

A new generation of water-resistant downs, like Sierra Designs' DriDown, seek to bridge this gap. Check out Ashleigh's review for some more info.

Wow!...this question has to be the question asked most frequently...maybe there should be a link to it (and other FAQ). I have chimed in on this issue before so I'll try to keep it brief (which is can be difficult for me).

As Seth wrote...the choice between down and synthetics mostly comes down to where you live (but this is only one of many considerations when choosing a bag...and probably not the most important...type of baffling...quilt vs. mummy...outer and inner fabric are probably more important choices). As Seth wrote down does not perform as well as synthetics in cold and wet conditions...and though the treated downs are much better there are questions about the durability of these treatments as one of the advantages of down is that it is more durable than synthetics (though being meticulous with your gear can mitigate this advantage significantly).

I personally use down when the temp is above freezing and the weather is dry and/or space and weight are serious concerns. For most of the year I use gear of choice is a DIY synthetic blanket (with little snaps around the edges which allow it to be converted into a traditional rectangle bag)...which I find perfect for late spring through early fall in all but the warmest weather (for the warmest parts of the summer I use a lightweight and compressible polyester "thermal" blanket...I made mine from a piece of fabric for 16.00...but the fabric used is very similar to the Sea-to-Summit thermal bag-liners for around 40.00). In temps below freezing I bring my down bag and my synthetic quilt...together these two pieces compliment each other well...because I use the synthetic quilt as a doing so the vapor from my body freezes in the quilt and not my down bag.

I am not sure where you are located...but where I live (Southwest Indiana) you do not need a 20 degree bag for mostly summers with a little fall and only need something in the 40 degree range (you can use clothing to off-set the temp difference...which is more versatile insulation). If I was forced to have only one bag for the time of year you are suggesting where I live...I would choose a synthetic bag or quilt with sewn-through baffles. The synthetic insulation can handle a wider range of weather conditions than down...and the sewn-through baffling will dramatically lower the cost (since the construction is so much less labor intensive). If you go for the quilt option you will save a lot of weight and space...and if you later decide you want to go into colder temps you can get a down bag and use a two-piece system similar to what I do (for a cheap down bag Walmart has a down bag: have been testing it since last spring [look for upcoming review] and though it is a little heavier and less warm than bags 4-6 times its cost...I have been very impressed with its performance to price ratio!)

I use a down mummy bag for three season solo use, even in august.  I'm a cold sleeper, and I can always just drape it over me. Th bag is a Kelty "Light Year",  20 degree rated, down women's size long. It fits me perfectly, compacts to nothing, weighs little and is very warm. The zipper only goes about half way or 3/4 down the side but that's fine by me.

I used this bag on as two week cycle tour of Iceland and it rained every day but two out of that time, yet had no problem at all keeping the bag dry and toasty.

Now when backpacking with my wife, we use a big Ray Way synthetic quilt.  The synthetic insulation used in this quilt is quite amazing, and I was inspired to made a lighter solo quilt and a sorta 1-1/2 size quilt that can be used solo or double in a pinch. I'm not sure I'll ever buy a sleeping bag again. The Ray Way way of making quilts is so easy and the new insulation is so fantastic.

But I'll use my Kelty down bag for solo use till it wears out, and that is gonna be a lonng time.

If properly cared for down lasts much longer than synthetic insulation!

I've just finished sewing a fleece cover for two side by side thermarest pads, with nylon pockets on the bottom to hold the pads in place. I'm gonna add velcro tabs to connect our big double quilt to this base for a real cozy double sleep system.

Growing up I used wool blankets and a WWII wool mummy bag growing up, not very high quality synthetic sleeping bags and dreamed of a high quality down bag all my life. When I could finally afford that nifty Kelty bag a few years back I was thrilled with it and still am. But synthetic quilts with the latest insulation also work and are very easy to make yerself. 



I think the moisture issue with down bags and the resulting loss of loft is an issue that is largely exhagerated.  Yes, it is true that as down gets wet it will clump and lose its ability to loft resulting in it not providing as much insulating ability.

IMO this is mainly only an issue in the Winter, and shoulder seasons when the temps are dipping below freezing. Aka when the insulating ability is absolutely critical.

So, yes it can happen. But lets look at all the facts here. In order for down to completely lose all ability to insulate it has to literally be drenched, as in soaking wet, as in you decide to submerge it in a river etc. If you take proper precautions and keep your down bag properly protected the likely hood of this actually happening is very very slim. Keep your bag in a waterproof stuff sack, wraped in a garbage bag, etc.

So what's the real threat to this taking place? Its moisture from the air/humidity, and moisture from you. It is true that after a period of a few days the down will begin losing a little loft. This isnt as dramatic as it sounds. We are talking about a degree or two of insulating ability lost about every 2-3 days. So if your out on a week or two long trip it can have a substantial impact over the course of the trip. If your only out for a weekend or a few days, it will make NO difference what so ever that you would be able to detect without some serious scientific testing.

Ok so, what can we do about it? There are a couple of things that all but completely mitigate this from occuring.

1) When you wake up and get out of your bag, immediately ball up your bag and give it a good bear hug and squeeze all of the air out of your bag. Do it a couple times. This literally takes maybe 30 seconds. What this is doing is getting all of that moist air from the night(from your body mainly) out of the bag while its still warm before it has a chance to condense inside of the bag/on the down.

2) If you take a rest break during the day, and or once you get to camp take out your bag and lay it out to let it air out. This works even better in a sunny spot. But anywhere will help, if its windy or sunny or both it works best. I personally rarely lay my bag out during the day on a rest break, unless its a reallly length break. I usually just immediatly hang my hammock as soon as i get to camp and hang my bags on it to get some air.

If you do either of those with any frequency the issue is negligible.

I too live on the East coast where there is frequently high humidity. I do those two steps and have absolutely zero problems with my down bags or quilts.


They dont loose loft due to moisture, so are inherantly warmer in conditions where they would be exposed to it. But if its wet, it will still be cold and uncomfortable, and pretty much useless...despite what anyone says. Try it one time and you'll quickly see what I mean. I spent many a night in the field in the military with a wet or damp synthetic sleeping bag.

Now, if I was going to be backpacking in a rain forest, like the PNW for example. I would use a synthetic bag. But for most of the country its really not as big of an issue as people make it out to be.

To me the benefits of down make up for this potential issue, and with a little preventative measures its really no issue at all/ very minor.

So from all that just remember:

Keep your down bag sealed in some waterproof fashion in your pack, and air out your bag when you get the opportunity and your down bag or quilt will always keep you nice and warm with its lofty goodness.


Thanks for the tips, and Rambler have you ever used Dri Down how well does that work if it does get wet by chance?

And by getting wet how wet are we talking? Like pouring rain or like condensation?

Thanks rambler....

I have some questions though about down bags....

Washing a down bag---that will help bring back loft, right?

And adding a liner (I use one I had my mom make me) help "protect" the bag against the moisture factor you mention? Although it still is a good idea to air the bags out....


I don't want to argue semantics...but I think exaggerated is not the best word to describe the down v. synthetic debate as it suggest a lack of truth. I can tell you that I use both synthetics and down...I do not have a loyalty (because I bought one or the other) or an ideological leaning (because I like the supposed "naturalness" of natural fibers) to either one...I think that both have their place. However...I fully believe that there is a significant difference between the amount of moisture synthetics absorb compared to least where I live and play (Southwest Indiana)...and for the typical outdoor adventure I get into (3-6 days). I also know that a lot of others (who have vastly more experience and knowledge than I have with my 20 years of playing outdoors) agree that there are times when down and wool are just simply not good enough (Andrew Skurka makes it clear in his book that his natural materials were not up to task in the wet-cold on Alaska's coast...similarly Chris Townsend finds wool and down unsuitable at times for a lot of Scotland's wet-cold conditions...still further...Fletcher and Rawlins make clear that natural fibers have their limitations...and that synthetics form the backbone of a backpacker's tool-box). As someone who lives and plays in more wet-cold than cold conditions I am inclined to agree with these I find wool and down unsuitable for the worst conditions that I experience in my adventures (I'm thinking about addressing this in a specific forum thread)...and I believe a lot of the down and wool praise that we are subject to is the result of where the heart of the outdoor+media+industry complex resides (out West!)...where these fibers undoubtedly shine compared to the rest of the US.

Having said all that...the difference between down and synthetic insulation is not the most important consideration (as I said previously) when thinking about what sleeping insulation to purchase...for most folks both will work well in most climates with the right knowledge and care (Ray Jardine uses only down as far as I know...though he also argues that sil-nylon is stronger than Cuben take his opinion with a grain [or shot] of something). Simply put...the difference between down and synthetic insulation in regards to sleeping bags is less significant than it is in regards to clothing...because our sleeping systems do not need to manage the extreme amounts of moisture that our clothing systems must (I would argue till I was blue in the face that synthetic insulation and fibers are far superior in cold-wet climates as part of a clothing system). To sum this point up...most backpackers need not worry about the limitations of natural or synthetic materials when it comes to sleeping systems...because they do not stay out long enough and/or do not use it frequently enough for these differences to matter...which is why I think other considerations far out-weigh your choice of sleeping insulation than down v. synthetic...if you choose appropriately in other regards it is more likely than not that both of these materials will suit your needs well as part of your sleeping system.

To conclude then...what you really should be thinking about is when and where you are going to be using your bag....and what bag best suits your specific needs. You suggested that you only intend to use the bag for a little bit of spring and fall...but primarily in the summer. Your profile says you are from Chicago (a place I lived for 6 years) I do not think you need a bag with a temp rating of anything lower than 40 degrees for the areas around Chicago in the summer unless you find yourself shivering frequently at night. Sure you can always get a bigger bag "just to be sure"...but you will pay considerably for this extra assurance in terms of dollars and weight (which will likely lead to sacrifices elsewhere that will improve your experience multitudes a good carrying bag or a lightweight shelter). is more likely than not that you will have that extra puffy (hot+stuffy) bag unzipped and only partially on you most of the time you are out. As I said previously...I would suggest you get a simple 40 degree bag with sewn-through construction (to save cost and weight) far as down or synthetic...unless you plan on using it a lot for the next 10-15 years (choose down in this case) I would choose which ever is cheaper as long as your choice of synthetic is one of the best available as discount and/or military synthetics are absolutely terrible (I made my synthetic quilt for 60.00 using a few yards of 1.1oz ripstop nylon and Primaloft One a few years ago...I have used it beyond count and it lofts as well as ever and keeps me warm through mid-spring to mid-fall for very little weight and space). IMO...too many people spend too much money+weight+space on their sleeping insulation...unless you do more lounging than walking your sleeping insulation is easily your most inefficient (i.e. weight v. rate) piece of gear you bring (insert sad-face). Personally I emphasize clothing over sleeping insulation...because insulation as clothing is more versatile (it works while I sleep and while I am awake and gives me extra protection against wet clothes). IMO...most folks calculate the value of their sleeping insulation more romantically than logically...the idea of lofty-goodness is a perfect example (I am not picking on Rambler...though we often differ I have a lot of respect for him and his perspective!). These unscientifically verifiable comforts (such as lofty-goodness) do matter (I use them myself). However...I think it is more important to calibrate your judgement based primarily on weight and versatility...a puffy bag is appealing to all of us (my bed at home is very lofty!)...but a more Spartan sleeping-system allows one to carry less weight and a smaller bag...which in turn provides more energy...less aches and pains...and more comfort overall.

What bag to buy is one of the "big three" endless and ongoing gear discussions; what shelter and what stove being the other two. I have read hundreds of posts on bags over the years and that is only on a small handful of sites.

The basic rule is "warm, light, cheap - pick two." The rest is just details. For your use, as I read it, a bag from a reputable company, whether synthetic or down will be fine. Synthetic bags are cheaper and bigger/heavier for a given temp range. If money is an issue, once you figure out what you want, look online for a deal or a used bag. 

The idea that down doesn't hold up well in damp conditions is, in my opinion, overblown. Down bags are often made with Gore-tex or similar breathable fabrics. I use my MacPac down bag in winter in Yosemite and it just has a taffeta or similar shell. I have stuffed it in a water-resistant bivy sack (an old BD winter bivy) and an overbag (older MEC Emperor Penguin) with no worries about it getting wet. In really heavy rain, I might choose synthetic.

Bag ratings are a whole other conversation. I took a TNF Cat's Meow (synthetic) to New Zealand and got rained on a lot, but the bag never got soaked, so that was a non-issue for me. I bought it because it was cheap and seemed like what I needed. The rating on it was overstated, though. I woke up hypothermic in it once at what I estimate to be around 25F, which surprised me a bit. The rating on my MacPac is spot on. I also have a Marmot down bag that I haven't used yet, but I think the rating on it will be accurate based on what I know about Marmot.

I have some questions though about down bags....

Washing a down bag---that will help bring back loft, right?

My Western Mountaineering bag needed washing so I did it in my backyard in a 50 quart cooler and some Nik Down Wash. The bag was rinsed out five times then I rolled it and pressed out as much water as I could, and spun it twice in my washing machine to get out as much moisture as possible. Then I just lay it out on a table for 4 hours. That completely dried it out. When I put it back in its storage bag it filled that bag up much fuller than it had before the wash.

So yes, washing a down bag will restore loft. I wash them both once a year and my WM down jackets too.

A good down bag should last you 20 to 30 years if you take care of it.

Down loosing loft from wetting out is way overblown. Plus the first rule of backpacking is keep your bedroll dry. LOL

A synthetic bag can loose a bunch of loft forever in its first year or two of use. Maybe they have had some advances in synthetic fill but probably not near as good as natural down yet? All of my high end synthetic fill jackets have lost loft that cannot be reversed and they lost it in the first couple years. They still work but not as puffy and warm as they were when new. The down jackets I have loft up just as much as they did 8 years ago. WM even replaced the zippers on all my down jackets for free and didn't charge me for shipping back to me either.

I use both synthetic and down. The difference is in the type of trip. For my canoe trips, I always use synthetic for several reasons. If I flip, I always have my bag in a dry bag, but in the event that it does get wet, the synthetic will dry faster than my down. I have experience with wet, very wet down. It take a long time to dry and IMO absorbs much more water than a synthetic. This of course, depends on the quality and original loft of both. One issue that is barely touched on is durability. A quality eider down or goose down bag will last many, many years with losing little of its loft. Care is the big factor here. Wash it carefully by hand, and carefully dry it. Don't wash too much as it will limit the life of the bag. Synthetics lose their loft over time, no matter how you treat them. All bags should be hung or put in bins for storage, not compressed or packed unless on a trip. My current synthetic bag is an REI Zephyr that has lost a lot of loft in the five or six years I have had it. My down bags are REI McKinley bags, which have nearly the same loft as when new.

There are many different synthetics, with some approaching down. Look online and you will find comparisons of the different types with details of how they are made. Beware of inflated claims, especially temperature ratings. I've seen rave reviews of cheap bags sold at Wal-Mart, but wouldn't recommend buying one for any kind of camping except maybe car camping in warm weather. I don't shop at Wal-Mart for several reasons, but cheap stuff of questionable quality with no customer service is one of them.

A brand name bag is an investment. Not everyone needs or can afford Western Mountaineering or Feathered Friends just as not everyone needs or can afford a Mercedes, but there are many other good choices.

Good customer service is also important on both the retail and manufacturer side. REI has a great return policy. STP (Sierra Trading Post) has good customer service. Marmot is great-I've called them a couple of times trying to identify a product I was buying second hand and they were very helpful. Marmot will wash and re-stuff or overstuff their down bags at a very reasonable cost. I just sent a jacket to TNF for repair so I'm waiting to find out how that turns out.

Good points Erich...I'm not going to argue anymore that there is a difference between the amount of moisture down absorbs compared to synthetics...everyone has their own perspective on the matter...but there is plenty of published evidence from reputable sources (some of which I cited above) suggesting that it does matter in certain conditions. With that the end I believe the type of sleeping insulation one chooses is simply not as important an issue as it is made out to be (that goes for absorption and durability). IMO focusing on other aspects (design) so that you only buy what you need will provide more bang for your buck when it comes to purchasing the right sleeping insulation for your needs.

In my comments above I wrote that if one plans to use the same bag a lot and over a period of many years then he or she should use down in their sleeping insulation...if treated well it will certainly last you a life-time. However...I do not believe one should put a lot of confidence in the belief that the sleeping insulation they choose today will be the what he or she is using frequently many years from now...because most folks who stick with outdoor activities (not just gear-heads) buy a new and/or additional sleeping insulation about every 4-5 years. The reasons for this are multiple...but a lot of it has to do with changing technologies and ways of enjoying the outdoors (you will do things differently outdoors in the future!) emphasizing the long-term value of down can be weighted too heavily in most folk's calculation. Given our often changing needs and choice of technologies...I ask how important is the increased durability of down over synthetics for most folks? This is not to say that a good generic down-bag is not a sound purchase (I have two myself....though the 2nd is an experiment) can be...but I think you should think about it as part of a larger process in which one is replacing and/or enhancing their sleeping insulation about every 4-5 years so that you do not buy too much today.

To summarize my points...if one falls into the every five years category (which many do)...the difference between the durability of down v. synthetic insulation is not necessarily the most important consideration (it matters...but it is not the most important factor). IMO...getting no more bag than you need for your needs today is the best can (and will) upgrade with additional or new sleeping insulation in the future...and for those rare instances that you need additional insulation beyond the baseline you purchase can bring additional clothing (which is simply good practice as it provides greater versatility and redundancy to your total kit for the often minor cost in terms of weight and space). Put can purchase a 32 degree down mummy bag and be done with will likely buy and carry with you more bag than you need 90% of the time...but it is there if you need it I guess (?). On the other-hand...a different approach would be to purchase the least amount of bag you need today with an eye towards future purchases which will either replace or enhance what you purchase today. For example...Mike suggest he only needs a summer a 40 degree quilt with sewn-through baffling is probably the least and cheapest amount of sleeping insulation he can purchase for his needs (saving cash and weight to improve he current kit today). If he believes he will be using this quilt for many years in the future and/or wants additional durability he could go with will cost a lot more...but a quilt is a very versatile piece of sleeping insulation that easily enhances other sleeping insulation as a durability is important if he remains an outdoor enthusiasts. If however...he wants to save money and/or he spends a lot of time (more than a weekender) in damp and/or wet-cold conditions he might purchase the quilt with synthetic is not as durable as down...but treated properly it will last a long time (as a quilt he will not smash the insulation like he would a bag).

Hey Tom...I have been testing a down-bag from Ozark Trails since last March (15 trips with nighttime temps ranging between 40-20 degrees Fahrenheit) is my take on it so far:


1) the temp rating is not at all correct...nearly 10 degrees off for a cold-sleeper like myself

2) the fill is 90% down and 10% feathers...but it is easily the equivalent of a 650 down bag

3) in the construction of the bag they chose to use too heavy of line-locks and zippers which makes the bag unduly heavy

4) the fill is a little light in the torso...but they really pack it in in the foot-box and hood which is nice


1) PRICE!!!.....69.99-79.99!

2) the foot-box and hood are roomy and snug respectively

3) 1.1 oz nylon is used on both the inside and outside of the bag...which help with loft...improves compression...and keeps the weight of the bag within the lightweight bag range

4) the bag uses internal baffling (not yet sure about the kind...but I am going to open it soon)


I am generally blown away by this bag...I have really put it through the its paces this year because I want to stand behind my review. To be sure it is not as good of a bag as one would get if you paid 4-5 times more...but for those cost savings it certainly excels above all bags I know of in the bang-for-your-buck ratio. I am always looking for discounted gear that is of good quality because I hate that having safe fun in the outdoors can be so prohibitively expensive...I think this bag is one of those pieces of gear that makes the outdoors more accessible to all of us...regardless of the socioeconomic class which we are tethered to.

I am a bit surprised by your mostly positive review on the OT bag Joseph.  I typically steer away from anything they make due to bad past experiences with their products.  It is good to know not all their stuff is bad.  Thanks for sharing.

Mike, Tom's comment above about different synthetics is well made. Much of what we have commented on here is to address your original question of down vs. synthetic. However, we should also be talking about types of synthetics and types of down, as well as construction methods, amount of loft, etc. Down can be eider down or goose, or plain duck down. Most low quality down bags today use plain duck. Eider is probably the superior, followed by goose. But any natural material varies depending on where the animal lives and not just the species. And while I like down, I choose it not for any adherence to its natural fiber, but for its effectiveness. I live in the PNW, on the wet side of Cascades, and use my down in conditions that are wet and above freezing, such as the Hoh Rainforest. My down performs well in these conditions where rainfall is well over 100 inches a year and humidity rarely drops below 90 percent. Where down really performs well is the weight to warmth ratio. As others have mentioned, I would also look at temp ratings with a grain of salt. My Mckinley bags never had such a thing. If you are too hot, unzip, too cold, put on a balaclava.

Jason...I was totally surprised myself...everything else by OT is complete garbage (IMO)...but while not a perfect bag the OT bag is surprisingly well done. I have plans to use the down from a jacket I purchased from the Goodwill for 5.00 to overfill the bag...I would guess I could bring the temp rating up another 10 degrees.

Thanks for the opinions, by all means didnt mean to stir up the fire or anything. Haha

But Erich some of those things you mentioned in your last post like different types of down and synthetic etc like Dri Down etc is it worth it? Any information on different types of the fibers etc I dont know a whole lot about the new technology I am looking to upgrade my old bag from like 2000 or so and I mean that was still using like hollofil II I believe so looking to make an upgrade essentially looking for a durable bag that can last at least a few years or so. 

Mike...I don't think you started anything...this is just one of those issues (like tarp v. tent) that is basically unresolvable because there are too many variables in the different practices and environments in which folks use down and synthetic insulation (tarps and tents). As I said before...I really think the type of insulation one chooses is less important than other factors (for the reasons I stated)...but I am only one perspective of many...and I generally tend to lean in the direction of lighter+cheaper+efficient as opposed to durable+redundant+expensive.

To help you with some of your questions here's a few links that I would suggest are from fairly reputable sources...or at least they attempt to be reputable.

Here is a nice primer on how to choose sleeping insulation from the guys at outdoorgearlab: keep in mind that these folks have a Western based perspective with a heavy emphasis on drier climates (though they still agree that synthetic insulation is better at managing moisture).

Here is a little primer on (a few of) the various types of synthetic insulation that are readily available: source is a little dated but I think very relevant for your purposes...where you will want to do more research is in the area of proprietary insulation as this is one of the fastest growing areas. For example...Thermoball is a synthetic insulation developed by Primaloft (my preferred manufacturer of synthetic insulation)...Thermoball is said to be more like goose down than any other insulation (a position which Primaloft already held with Primaloft One) and yet it is still said to  maintain all the advantages of synthetic insulation. It is difficult to track down information on Thermoball...but Philip Werner (AKA SectionHiker) who once wrote for Trailspace (what happened there?) has a little information on his site here:

I have had a lot of trouble tracking down information on polymer treated downs that weren't directly pulled from the marketing materials of manufacturer' for now it seems the appraisal of these materials will necessarily be based on the judgements of others...which typically means a measure of over-enthusiasm of at least 2 standard deviations:-)

Mike Stelz said:

Thanks for the tips, and Rambler have you ever used Dri Down how well does that work if it does get wet by chance?

And by getting wet how wet are we talking? Like pouring rain or like condensation?

 I have not, however there is a good review by Arson here on TS of a  jacket with dri down, but i forget the name of it off the top of my head. I have no first hand experience with dri down, but it seems very promising from i have read and seen online.

kevinumberger said:

Thanks rambler....

I have some questions though about down bags....

Washing a down bag---that will help bring back loft, right?

And adding a liner (I use one I had my mom make me) help "protect" the bag against the moisture factor you mention? Although it still is a good idea to air the bags out....



Washing a down bag PROPERLY will indeed bring back loft. However, this assumes that the bag has been stored properly and treated well otherwise. If its been stored compressed for a long time the loft may not ever be recovered.

Do not be confused by my previous posts, loft lost due to wet or damp down will return when the down dries. You don't need to wash and dry your bag just because it got wet.

Adding a liner just helps keep your bag clean, unless your using a VBL it wont help with moisture. A VBL sleeping bag liner is rather rare, and i would imagine, uncomfortable.

I wouldnt pay any attention to whether a bag is goose down or duck down. As long as its pure down and not feathers, and 650 fill or higher its fine. It is generally thought of that goose down is "better" but this is really just because its bigger and requires less of it to fill the same space as duck down. Many down bags advertised as 650 fill are either all duck or a mix of duck and goose downs. Its really only pure goose from 750 up from my experiences, but not always.

Most items made of 750 or higher down are pure goose down. Duck down works just as good as goose down, but its generally viewed as a budget down. Its smaller, and thus takes more of it to take up the same space as goose down (hence the lower fill numbers). Duck down is typically found in full or part in budget down bags, absolutely nothing wrong with it, its just  a little heavier.

Fill power is the measure in cubic inches of how much air/loft volume an ounce of down will occupy. for 1 ounce of 900fill down will occupy 900 cubic inches, 1 ounce of 650 fill will occupy 650 cubic inches etc.

Fill power does NOT mean warmer. The higher the fill power just means the less down is needed to accompish the same result. Higher fills are lighter and will compress smaller.

Rambler, I have to disagree regarding goose and duck down. Goose is not necessarily bigger, depending on where the goose or duck was raised and how old it was when the down was harvested. Often, we think of goose as superior to duck down, but that is not necessarily so. Goose down can be of lesser quality than duck, if the goose was not mature. As well, "mature" down retains its loft better over time. And I think it is important to point out that warmth of the down is more than just the loft, though the latter does a reasonable job of giving a warmth factor. Eider ducks are a sea coast duck and that down is superior to goose or other ducks. I think that Mike's question doesn't necessarily relate to the performance of the various downs, but I think it important to note the differences. Here is a link to an article about the differences.

Other factors governing the warmth of a down bag, include outer material used, baffle system, and overall design. The latter should be noted by Mike. Close fitting mummy bags will be warmer, all other things being equal, than a looser, roomier bag. Many people don't like a true mummy and few of those are made anymore. Heavier materials may make the bag more durable, but can also reduce loft in down bags. Further, the underside of the bag is often not addressed. Compressed down provides little insulation. Yet the compressed down between you and your sleeping pad is still there, and you still carry it and paid for it.

Erich, you badically said the exact same thing I did just worded a little differently. So we actually agree.

Most reputable manufacturers nowadays use mature down, my post was more of a generally speaking point of view. So if your comparing apples to apples goose down in generally better.

A piece of Down isnt warm at all, its the air it traps that provides warmth aka its loft. A piece of down itself provides a negligible amount of insulation, its the dead air space that provides the warmth, and that is true of most any insulation.

Oh wow!...this thread just got technical (love it!). Since we're splitting hairs I would just add that at the practical (perceptible) level the statement one type of down is not warmer (just heavier) than another is basically true...but at the imperceptible level the material which traps the air does matter...because different materials conduct heat differently (Klymit uses Argon gas instead of air for this reason...which is ridiculously impractical and an imperceptible decrease in conduction)...and is why manufacturer's and others can technically claim one down to be warmer than another.

Going further with Erich's comment about the underside of a bag...the lack of insulation that compressed insulation provides on the underside is one of the reasons that quilts have become increasingly popular. The weight savings (not always a cash savings due to small number of manufacturer's) can be significant in that z-packs offers a 30 degree down quilt at 14oz which is comparable to the 32 degree Western Mountaineering Summerlite at 19oz. To put that weight savings into context...that's the weight of my cook-set! I should add...that while I prefer to use my quilt for nighttime temps between 70-40 (most of the year for me)...when the temp drops near freezing I prefer to use my mummy-bag (my mummy and quilt together if the temp drops below freezing) because it offers two advantages...the mummy-bag fits more snug around my whole body...and it moves with me better inside my bivy. I should also add...that because I am compressing a bag with my body more than I would with a quilt...I prefer down-bags over synthetics...though as I said...if I could only choose one piece of sleeping insulation it would be my synthetic quilt hands-down because it is more practical for more of the year (and I would argue is the more practical and economic choice for folks who are only going to be backpacking between late spring and early fall).

Finally...I also want to add that the poor reputation of feathers is sad...because for the majority of people who use sleeping-bags and quilts...a bag or quilt with a light feather mix (no more than 10%) would be an excellent choice (for most folks a 900 fill bag is just showing off). That is...if you don't mind the marginal weight and compression differences (sadly most budget-bag makers shy away from lightweight fabrics that would minimize the weight and compression differences between budget and professional bags) a bag or quilt with a light feather mix offers some advantages beyond the HUGE!!! savings in cash (savings which could be used to purchase a lighter shelter or better pack...which would increase the happiness and comfort of these folks on the trail magnitudes more than having a slightly puffier bag that they only use while sleeping and which they find too warm for most of their outings)...because a light feather mix performs better in wet-cold conditions and resist compression due to the use of heavier fabrics (900 fill-power is great...but without ultralight down-proof fabrics and really dry conditions you are wasting a lot of money).

Crap...I just realized that the link a pasted to the primer on the types of synthetic insulation available was the wrong is the correct one:

Also...I recently learned (from Mr. Werner) that he was only writing as a guest...and that he is good friends with the folks here at Trailspace. To be clear I wasn't being snarky or negative when I asked...just inquisitive...because I have a lot of respect for Mr. Werner's knowledge+perspective+love of the I thought I'd write a little something for the sake of clarity.

Joseph, I think the real issue with cheap bags is quality control. I read reviews on Wal-Mart's own site by bag owners who had them start to come apart almost right out of the box, while others thought they were great for the price. As I said before, not everyone needs a top of the line bag and in many cases, would be better served spending their money on a better shelter. My theory is that you can survive with a cheap bag in a good shelter better than in a good bag in a shelter that leaks or starts to come apart in a storm.

That said, I have spent a few days in relatively heavy snow in my winter tent (bought used in eBay) and my down bag and am quite happy with both. I camp alone so have no interest in having to wonder if my gear will come apart if the weather turns on me.

There is somewhat of an "arms race" on fill power. My Marmot bag, a 1993 vintage Alba, is rated -10F/-23C and is 650; my MacPac from the mid 80's is rated +23F/-5C and probably the same fill. My TNF Baltoro down parka is newer and 700. The latest version is 800. Higher fill power means higher price and less weight, assuming the shells are the same, for the same temp rating. It is easy to confuse fill power with how warm a bag or jacket will be. The best way to compare is the EIN standard test, but not all manufacturers in the US test their bags that way. Almost bags sold in the EU are EIN rated and even that test requires an understanding of the test results.

If interested, here are the links to four Review Core reviews of products using newer down technology.





Note: Concerning the two sleeping bag reviews, both me and Gonzan experienced a clamminess (humid skin feeling) with these products.

Hey Tom...since my response to you (and many of my replies on this thread) was/were reading like a product review I have decided to start one. I plan address the issue of quality control there (which is a good point...but not one I would suggest is reason to avoid this bag for those I believe it is most appropriate for).

Good idea. I think reviews may get more looks than any one particular thread.

Tom D said:

Good idea. I think reviews may get more looks than any one particular thread.

 I agree, good idea.

December 1, 2020
Quick Reply

Please sign in to reply