Down vs synthetic sleeping bags

My main question here is:

If a down bag is treated with good proofing (Nikwax? or is there anything better?) will it be as reliable in damp conditions as a synthetic bag?

It’s a general question, but the specific initial requirement is for my 14yo to take on a trip to Vietnam, where (a) it may well be humid and rainy and (b) he will have neither time nor inclination to rigorously dry the bag if it gets wet—it needs to cope with a “very probably lazy” user…

I’m keen to get something as compact and light as possible (without NASA levels of investment) and on paper the best approach looks like an entry/mid level down bag and some proofing; I’m just not sure whether it’ll be up to the job.

All experience and suggestions welcome, thank you 🙂

My only experience is from a 4 day backpacking trip through the Swiss alps with my Alpkit down sleeping bag.

Even in good weather (although actually pretty chilly at night), I woke up with the bag feeling a little damp in the mornings (just from sweat I guess) so left it out to air for an hour whilst we did breakfast and packed up camp each day. I was a bit paranoid though as it was a new bag.

I used a silk sleeping bag liner too, which helps absorb any sweat, and would be a good idea if you go for down.

Personally, I would probably go for a cheaper synthetic one that he doesn’t need to be careful about. But in answer to your question I don’t really know what the limit of a proofed down sleeping bag would be in terms of getting wet. Down doesn’t like being stored/compressed if it’s wet though, that will ruin a lot of it’s loft.

I’m guessing vietnam and it’s humidity won’t be particularly cold? So even with a synthetic bag, he can probably get a smaller/light one?

The kit list advises a comfort rating of zero Celsius, but to me that seems somewhat pessimistic for Vietnam in July (not that I’ve ever actually ever been to the region myself)…

I would go for synthetic in your position as it will be humid and whatever levels of care/ airing/ etc you would expect to do, kids will get nowhere near that. My son has a 2 season Rab something that my parents bought for him one Christmas. It’s been ideal for everything from cold uk camps, dossing on floors, hot summer camps..and is small and light.

Edit – it’s a  Rab Ignition 2.

I’d go with a synthetic bag.

Down is a compromise of faff Vs weight. If it’s really cold then you might accept the added faff in return for not having to carry the weight.

In summer the weight difference is less so the faff is less justified. If you’re looking at

Wet down takes forever to dry, and has zero insulation value.  Whereas synthetic insulation you can wring out the excess water and it will return to about 50% of it’s r-value immediately.

Hydrophobic down bags will shrug off spilling a drink (it’ll run off), air out clammy sweatiness quicker than old down bags, and a bit better at resisting condensation from the tent wall. But they’re not invincible, if your feet are against a wet tent wall they’ll get cold and wet.

That said, my next purchase will be a down quilt for summer use.  But it’s one of those things where I’d buy one thing and recommend another. If he doesn’t understand the compromises then it might end up a shivery 4 day hard way to learn about them if it rains on day 1.

Having been to Vietnam in July – i’d be surprised if you needed a bag that warm unless he’s planning on going into the mountains or similar? It was 40C and 100% humidity when we were there (Saigon, Danang, Hoi An, Cat Ba, Hanoi).

Is he tenting? Could be pretty miserable without AC. I think staying cool would be a bigger problem than staying warm. I slept on the deck of a boat at one point with not even a sheet and was pretty comfortable hah.

I’ve been to Vietnam, sleeping in non hotel environments (shall we say).

You do not any sort of sleeping bag unless you’re in the hills. I had a cotton sarong; I got a silk sarong made in Hoi an.

Packs down ultra small. More than warm enough. If in doubt, just get a silk sleeping bag liner.

Never been but according to this site it’s hot and humid rainy season so I wouldn’t be taking a down bag.
https://www.roughguides.com/vietnam/when-to-go/july/

Maybe a one season synthetic bag, but from the last couple of comments it sounds like even that might be overkill. Also consider pack size – any synthetic sleeping bag will take a decent amount of space, a sarong not so much. Is the boy going to be hiking and carrying his own kit, or just buspacking?

My personal use sleeping bag/quilt approach is all down, although clothing is synthetic

The stuff I use with the kids, and by the kids, is all synthetic. Easier to manage and care for, and cheaper, but bulkier

For Vietnam in July I would get one of these https://amzn.eu/d/6ljgqmT and take a cotton sheet!

For knock-about stuff, I’d definitely go synthetic. Something like a Mountain Hardwear Lamina will give him a good balance of warmth, lightness and water resistance and won’t turn into a soggy mess if it does get soaked. Down is fine, but you need to treat it with a certain level of respect to keep it happy, even water-resistant factory-treated down.

If a down bag is treated with good proofing (Nikwax? or is there anything better?) will it be as reliable in damp conditions as a synthetic bag?

Fwiw, ime, the main plus of water-resistant down isn’t so much that it keeps you warm when it’s damp – synthetic is better – more that it recovers to close to original state when dried out, whereas untreated down will tend to clump unless agitated during drying. But in this case, synthetic sounds like a better choice. If you wanted to be really fussy, PrimaLoft did/does a fill called PrimaLoft Down Blend, which was a mix of hydrophobic down and PrimaLoft synthetic fibres, that was a very good, but niche, mix of the properties of both. Not cheap and not much around.

There are a few versions of the MH Lamina. I’ve got the 45, after recommendations on here for a summer bag. It’s decent for chilly summer nights. Sounds like it might stay in the bag in favour of silk or cotton in Cambodia, but if he’s going up high, maybe a good option to have.  But if he’s going up high and not camping, most places would have blankets to use, wouldn’t they?

The kit list advises a comfort rating of zero Celsius

Gulp – where are they going?

My experience was sleeping outside of an aircon hotel room was an exercise in feeling claustrophobic in your own skin with the temperature and humidity!

Some interesting point about down vs synthetic – I’m also looking for some sort of “summer weight” quilt for damp climates that is really compact (without spending the GDP of a 3rd world country)…

But, frankly, I’d be asking who recommended the kid to take a sleeping bag and, more importantly, why?

But, frankly, I’d be asking who recommended the kid to take a sleeping bag and, more importantly, why?

This. Really. Who is he going with that recommends a 0°C bag (comfort, not even extreme) for a country where the record low in the coldest region is 12.2°C for that month? And what else haven’t they looked at properly?

Found in 1 min on google:

https://en.wikipedia.org/wiki/Climate_of_Vietnam#Central_Highlands And they’re probably not going there.

Record lows probably also available for the areas they are going.

My son went to Borneo with World Challenge, they had a similar recommendation on sleeping bags

We bought a silk liner, rectangle shape for legroom,  grey not white so not to show the grime – he slept in that.

He took a cheap sleeping bag from Aldi, it was £15 and lighter than decent synthetic ones we had. We knew it didn’t need to be v warm. It was there to show willing on the kit list  it came back used just to sleep on.

We were nervous doing this, but a couple of his friends did similar and we figured at the time they were 18 years old and could find out how to buy warner sleeping bags over there if they needed them.

Synthetic. Just cheaper and easier when not looked after.

The only time my down bag comes out is for bike packing as the Synthetic ones we have really are too big and bulky.

Thanks all, useful stuff. Certainly confirmed my suspicions about the recommended bag warmth 😂

My son went to Borneo with World Challenge, they had a similar recommendation on sleeping bags. He took a cheap sleeping bag from Aldi, it was £15 and lighter than decent synthetic ones we had. We knew it didn’t need to be v warm. It was there to show willing on the kit list  it came back used just to sleep on.

This is World Challenge too. I guess they just don’t tailor their standard kit list as much as they should.

I’ve taken the same approach having done some more looking last night: the Ordnance Survey shop (which I never knew sold kit) had the Robens Moraine 1 bag reduced to a bargain £30, and I think I got the last one. It’s 615g, packs small, and is rated at 11 degrees, so on paper it’s as well-suited as anything else I’ve seen. Ticks the box without being too much of a burden, and may even be thin enough to get used.

Certainly not judging anyone else for their choices but I have always struggled with the idea of down. It is the whole live plucking thing, there are places that tout “ethical down” but I read one quote from a boss of Rab I think where he likened down to cocaine, making the point that batches are mixed in the supply chain and no amount of certification can guarantee what you are getting.

I bought a snugpack softie elite 3 about 13 years ago that is going strong. I use it for frosty up to snowy conditions and a mountain hardware lamina for pretty much everything else (I sleep very warm though).

In those 13 years my bikepacking buddies have all suffered with damp issues at some point in their down bags, especially when using a bivi bag, in most cases high spec breathable bivis too. They have all tried treating their bags but to no avail. Despite having down bags rated to lower temps they have all complained of cold/damp.

Not saying they are doing things right, sure countless mountaineers etc can’t be wrong about down, but just what I have seen.

In that time I haven’t done a thing to either of my bags.

The weight penalty doesn’t bother me so much (though it is a big difference) as we don’t usually try very hard to cover distance but the main issue I have with synthetic is the pack size as I struggle for bar/tyre clearance. Apart from that I haven’t seen anything that would tempt me to down.

One pal bought a PHD synthetic bag and that is a pheonomenal piece of kit in terms of quality/pack size/features/weight.

If I get another bag it will be a PHD if funds permit.

Also in addition I forgot to mention the snugpak jungle bag i use in the heights of summer. Built in mozzie net is ace. Not sure on the temps at vietnam but might be worth a shout, they are pretty cheap.

My son went to Borneo with World Challenge, they had a similar recommendation on sleeping bags. He took a cheap sleeping bag from Aldi, it was £15 and lighter than decent synthetic ones we had. We knew it didn’t need to be v warm. It was there to show willing on the kit list  it came back used just to sleep on.

I think I’ve probably got the same one.

It’s just about useable in the UK in summer, I found I’d wake up at ~3am and have to really mumify myself in it to warm up, but could get back to sleep.

Quite heavy material and not hydrophobic though so there’s definitely a benefit to spending a little bit more.

Vietnam you say?

It’s going to be hot and wet. That’s nice if you’re with a lady, ain’t no good in the jungle….

the whole live plucking thing

I confess I did not know about that 😬