Waterproofing Sleeping Bag

[Cotton Terry]

Keeping a sleeping bag dry is very important to performance, particularly down filled bags. I have never heard of anyone applying silicon waterproofing to their bag like we do with our tent rain fly. Why wouldn't this work?

[mudsocks]

You'd trap moisture from your body inside the bag causing the down to clump/loose it's loft which would drastically reduce it's ability to insulate.

[Damn Yankee]

zip up bag, do all Velcro, use large front load washer at laundry mat(home front loads aren't large enough)you need to wash the bag inside out with DWR, run an extra spin cycle to get the excess water out. After pulling from washer, turn right side to and apply spray on waterproofing, throw in large capacity front load dryer and dry on low heat. Check periodically and make sure the bag is dropping from top of dryer barrel as this will make the down puff(or use new tennis balls. Continue to check periodically until bag is dry, could take a couple of hours, be patient.

[HooKooDooKu]

Seems to me if you are that worried about your down getting wet you need to switch to synthetic.

I personally love the Mountain Hardware Ultralamina series of sleeping bags. While these bags do weigh a little bit more than down bags costing $$$ more, it seems to stuff down better.

As an example:
Marmot Plasma 15 v Mountain Hardware Ultralamina 15
Weight: 1lb 14oz v 2lb 13oz (avg total weight regular size)
EN Rating: 29 v 24 (comfort level)
Price: $500 v $275 (full retail)
Stuff Sack: 7.5 x 15 v 7 x 13
Fill: 875 Goose Down v Synthetic
Size: 83x30 v 78x30

[Trailweaver]

Have you ever spent the night inside a large plastic garbage bag, say maybe, in July? Think about this for a minute before you waterproof your sleeping bag.

[squeezebox]

What about a bivisack? or a 1 person tent?

[PD230SOI]

I would not treat a bag. If it was a good idea wouldn't it be an option from the larger companies?

[Toolshed]

You want the moisture to freely flow through your bag and then evap outside your bag. Treating it will hold all in your sweat keeping down clumpy and reducing performance.. Most references to keeping your down dry are from the inside of the bag, not so much the outside. Especially in winter. If you don't take care your bag and expose it to the sun or a breeze during breaks and meals, will get heavier and heavier each day and you will sleep colder and colder.
I agree with your thoughts, though, a mild DWR treatment would at least keep dew at bay. The trick is making it work...
FWIW, I had heard of tests years ago with eVENT and GTX, but the materials were too heavy (and not breathable enough) and compressed the down, severely reducing performance.

[Cotton Terry]

Thanks for the feedback. It's not a big deal, just wondering. However, if evaporation of moisture is the issue, I wonder why they don't use a Goretex-like material.

[Hikes in Rain]

I'd guess we produce it faster than it could pass through the Gortex. I've got it on my trail runner shoes, and my socks get damp with perspiration despite it. There is a treatment for the down itself that helps it repel water. Look for Dri-Down in the descriptions.

[kayak karl]

Thanks for the feedback. It's not a big deal, just wondering. However, if evaporation of moisture is the issue, I wonder why they don't use a Goretex-like material. probably weight

[Connie]

If you are concerned, treat with DWR.

If still concerned, purchase or DIY/MYOG a bivy.

[Kerosene]

Another, simpler option that will handle most situations is to use DWR spray only on the foot-end of the sleeping bag. Assuming you are reasonably careful, in most cases your bag will contact water blown in from the shelter opening (assuming you are sleeping head-in) or the foot of your bag brushes up against the condensation at the end of your tent (or it even slipped outside for a bit if you're sleeping on a slight incline!). Of course, the full DWR wash will work as well and retain breathability.

I haven't experienced severe enough conditions to move me to a synthetic bag weighing almost a pound more. Just not worth it in my opinion. The new DryDown treatment (where each down puff is waterproofed) is a bit more promising to me.

[shelterbuilder]

I believe that they did try to use Goretex on sleeping bags when Goretex first made its debut, but it never did work properly. Problems with the insulation retarding the passage of the water vapor to the outside layer of the fabric. Just keep your sleeping bag dry during the day, and you'll be fine.

[Sailing_Faith]

You could try a low cost experenment with a bivy sack made from tyvek or even cheap harbor freight tarp material... See how it sleeps and works for you.

I suspect that like countless others you will find a bivy sack type arrangement (like you would have with a waterproof sleeping bag) will prove less then satisfactory to you... But you can try it.

good luck,

[Franco]

Feathered Friends used Gore-Tex for their sleeping bags, they now use the water resistant Pertex.
The type of Pertex I had on another brand of SB was somewhat heavy compared to the fabric used by Western Mountaineering and the like.

[Connie]

I had the foot of a sleeping bag wet one time only, from sitting in a puddle on the tent floor. I was still warm. No more tent floors for me. It was Long Beach, Washington State coastline, near Oregon, after days of steady rain downpour.

One time, in 50+ years of using down sleeping bags.

I would say, get over your fears and work on getting skills that will keep you and your gear as dry as you need to be.

[MuddyWaters]

Good down bags are dwr treated, tight weave fabrics.

This makes washing them difficult
And especially rinsing them. The tight fabric prevents much water movement thru bag
It is really not easy to wet out a good down bag, even floating it in a tub of water. Its a slow process.

Cheap bags with poor fabrics may wet much easier

Condensation of body moisture is much bigger worry usually.

[CalebJ]

Gore Tex was definitely tried as a shell material in the 70's or 80's, not sure exactly. It's just not breathable enough. They started using DryLoft as an alternative, and some companies (like Feathered Friends) had PTFE generic equivalents to it. Since then, the other shell fabric alternatives have improved immensely as well. I'd rather spend the time making sure the bag doesn't get wet in its stuff sack and that your shelter keeps the water off of it. No real worries past that.

[Cotton Terry]

No fears, Connie. I was just wondering why.

[Connie]

I won't use a tent floor, because I can't see if the ground is saturated and pooling water. Other people use a waterproof cuben bathtub inner net tent floor, or, bathtub cuben bivy. I choose well-drained soil and Gossamer Gear translucent polycryo ground cloth so I can see for myself, or, pick up an edge. However, I hike where there is well-drained soil available. If not, I would have a cuben bathtub floor.

I have been thinking a great deal about this, because I want to section hike the PNT Pacific Northwest Trail. The Pacific Northwest can be wet, wetter, and wettest of any hikes I have experience.

[rnpastor]

I'd be concerned about: 1. Moisture retention. 2.Degradation of the down filling. 3.What would happen w/ the bonding of the bag material and the silicon. An aside: I like my SOL Escape Bivvy; size: 84" x 31” and 8.5 oz. It’s all I’ve needed for late Spring, Summer, and early Fall. During Spring or Fall, if the weather predictions look like I may need more protection - I use my military poncho-liner; size 62" x 82” and about 20 oz. For shelter I have a Wilderness Innovations tarp (10’ X 10’). They just came out w/ a ‘blanket’ that may be an all round option, I’ve not tried it but it looks interesting and they report all season: size 84” x 72” and 3 lbs 4 oz. ( http://wildernessinnovation.com/shelter/personal-survival-blanket/#sthash.CivvEJO2.dpuf). Stay well, david

[Powder River]

I once put the foot of my sleeping bag inside a plastic bag to keep the moisture of the tent roof off. I woke up and my legs and sleeping bag were soaked through with sweat. It wasn't a good idea

[shakey_snake]

Thanks for the feedback. It's not a big deal, just wondering. However, if evaporation of moisture is the issue, I wonder why they don't use a Goretex-like material.

Because a gortex-like material that works well enough doesn't exist. Gortex may permeate more vapor than a completely impermeable material, but it still isn't quite good enough to replace non-waterproof materials that have to pass a lot of vapor.

That said, some custom quilt manufacturers will let you use a material with a Durable Water Resistant (DWR) finish at the head and foot area (the most likely areas to be wet with morning condensation.

[shakey_snake]

Sorry, Durable Water Repellant

[handlebar]

I once put the foot of my sleeping bag inside a plastic bag to keep the moisture of the tent roof off. I woke up and my legs and sleeping bag were soaked through with sweat. It wasn't a good idea

I've zipped up my rain jacket (eVent) and slipped the bottom of my sleeping bag into it to keep from getting moisture from condensate near the foot of the tarp. I figured the eVent should let the water vapor go thru and the dwr coating on the rain jacket should keep the condensate out.