A built-in VB in a cold-weather quilt – a good idea or not?

If committed to conditions requiring a VBL it sounds intriguingly good.

It is committing the quilt to those conditions however.

Well that’s the thing – Huzefa claims the quilt can be used in any conditions without getting clammy, and a couple of reviewers on his site agree.

I think he uses the VB even on his lighter models.

This does take a bit of believing though. I think I might ping him for clarification.

“Well that’s the thing – Huzefa claims the quilt can be used in any conditions without getting clammy, and a couple of reviewers on his site agree.”

Somehow I don’t think two individuals will ever have the same standards of “clamminess”.

In the building world, if a person installs a vapor barrier on one side of their wall assembly, the LAST thing they should EVER do is install one on the other side. That would lead to deterioration in the wall assembly. Moreover, installing ANY vapor barriers in homes is now subjugated to the coldest of environments.

To me: creating a waterproof outside shell with a built-in VBL on the inside sounds like a recipe for disaster in the long run.

For one of these quilts to compress, air MUST be exchanged inside the Apex insulation. So if I’m sleeping in a tent where the air around me is mostly saturated, please explain to me why the air surrounding the Apex is any different than the air in the tent itself? And when the vapor inside the Apex does condense (which it will), how easy will it be to dry out?

Call me skeptical, but it’ll take a lot more than a few anecdotal reviews to prove to me that there is something novel in this design.

Brining along an inside VBL that I could separately dry out, or wearing a VBL suit just seems like a much safer and more versatile option.

Matt – interesting contribution

The outer shell on the Blue Bolt isn’t advertised as waterproof – I suspect it’s a conventional tight-woven taffeta with some DWR. It must be, or things could get very nasty as you say…

Yes – after I posted it did strike me that a separate VBL might work better. A minimal bag liner would add maybe 80 grams, but according to Ron Bell it would also add around 5F of warmth so it’s far from dead weight. And if you’re in dry and sunny SoCal in the summer, you could leave it at home!

You could still have the option of putting the quilt over your head if you simply lined the top few cms with a VB fabric to prevent the breath getting into the insulation. That idea I do like.

As an additional benefit, he’s claiming that the VB: “Adds 5 to 10℉ to the base temperature rating by minimizing heat loss that happens through evaporation and minimizing convection heat loss through the fabric weave.” I do think this is credible, and helps offset the added weight and bulk of synthetics.

I’m a sucker for innovative little cottage startups and love to see them doing well. But when you see something relatively obvious like this you do have to wonder if there’s a good reason that no-one else is doing it. I suspect HKNewman is right and this is best reserved to genuinely cold conditions, where it might well make sense if it’s well executed.

I’ve been using down in the UK and Alps for 50 years, and in those conditions I’ve never had a significant problem with losing loft, even in torrential weather. Perhaps this is a solution looking for a problem?

Tim Marshall at Enlightened Eqipment, very early in the business when he still did custom work and such, used to make some cuben quilts, so having a built-in VBL isn’t a new innovation. He also made me a ‘normal’ down quilt system which included a cuben VBL quilt liner which snapped into the quilts, it was a great system (I no longer have the quilts, though I still do have the liner).

His first iteration of the cuben quilt, iirc, had a narrow (maybe 8″?) fabric panel down the middle of the outside of the quilt so it could breath. His second iteration, iirc, was all cuben, but had an opening with collar at the foot end (much like attaching one of those inflation bags to your sleeping pad) so you could fluff the down within, and so air could escape to stuff the quilt into a bag.

I owned each of those iterations. I thought they worked quite well – in colder weather. Regardless of what anyone might say, a true VBL in warmer weather would be clammy and sweaty as heck for the vast majority of people, imnsho. I’m a big VBL fan in colder weather though.

“You could still have the option of putting the quilt over your head if you simply lined the top few cms with a VB fabric to prevent the breath getting into the insulation. That idea I do like.”

This has been done as well. I think Javan Dempsey (I hope I’m spelling his name correctly, he made some fabulous stuff quite some time ago, quilts and small knives and such, but hasn’t been around BPL for a long time now. Too bad, he was good people) made a quilt with a VBL lining at the top 8″-12″ for just that purpose.

I believe Gryphon Gear’s Taurus VRB is what you are looking for.

“Gryphon Gear’s Taurus VRB (they’re well known over on reddit)”

Sorry, a bit of drift here, but it’s interesting to me the stuff that’s often recommended on r/ultralight as compared to here. Never heard of Gryphon Gear til I saw it mentioned on reddit. Same with Timmermade stuff, and Cumulus bags (from Poland, I believe).

Thanks Idester – sounds like the quilt-hood with VB lining concept has some legs.

You do get good ideas that don’t make it into the mainstream – I’m thinking of the Pacer Pole, for example. Perhaps this is one of those?

Yup. I’ve heard good things about the company. Sorry for the edit : /

We cross posted. The Cumulus bags are quite well known in the UK and are fantastic value. Quality is fine, by all accounts.

If Gryphon’s ratings are accurate, you do seem to save a few grams as a result of the VBL. It’s not as much as it looks initially because it’s hoodless, so you have to allow extra weight for a head covering. On the downside (pun intended) you get a very specialised bit of gear and a lining that looks a bit uncomfortable.

As a maker they have a 60/40 distribution of the down on the top of the bag. The idea of the hoodless bag is that side sleepers can turn inside the bag without it turning with them. That way the warmer part of the bag stays on top and you aren’t breathing into the hood.

I really do wonder how realistic this is – because if the bag does turn, you’re going to have a cold butt. And in my experience the bag will turn…

. CUBEN QUILT FROM 2009 .

. 10OZ CUBEN FIBER QUILT .

. CUBEN / DOWN QUILT .

. ENLIGHTENED EQUIPMENT CUBEN IS BACK .

Any of you guys ever seen the original version of the Warmlite Stephenson Catalog?

outinunder.com/sites/default/files/Warmlite%20Catalog%201974.pdf

https://www.   goes in front of the above for a complete address

Warning! There’s a lot of nudity. I didn’t make the link active for that reason.

But there’s also a lot of ‘splaining of the whole concept of VBL

I still have one of the bags upstairs in the closet. The “fuzzy-stuff” vbl liners were/are indeed fuzzy and very comfortable. The bags worked GREAT. It’s just that they were/are heavy with all the zippers for the multiple layers and the D.A.M air mat, and bulky. I’ve been thinking, but haven’t gone past that; of whether one could re-configure the system to use something like an X-therm modded to fit in the bottom mat layer but just seems sorta like a tail chasing exercise.

I have seen the original catalog, I owned a Warmlite tent back in the day. Interesting family history.

Thanks for the links Link! What a fun trip down memory lane!

You can also contact this company:  https://www.rbhdesigns.com/

They do custom vapor barrier clothing and could probably make anything you need with their vaprthrm fabric.

VBL clothing is a better option, IMO.

About 10 years ago I was using one of Tim’s early Cuben quilts. Forecast was for temps around 32F, which was the rating for my quilt. A freak storm came in and temps dropped to around 17F.

My only option was to put on my down jacket, knowing it would probably get wet/damp. I put on my Houdini under the jacket hoping to mitigate some of the moisture I expected, but it didn’t help much. With a VBL shirt the down jacket could have been worn over it and would not have gotten wet. Fortunately that night was the last night of my trip.

Of course one wouldn’t normally be wearing VBL clothing in those temps (32F), but what is the strategy with a VBL quilt lining if temps go below the rated temp of a quilt/sleeping bag? Any additional insulation (down or synthetic) is going to get wet. And for temps where people use VBL, wet insulation layers would be a huge problem. In really cold weather, VBL clothing can be an asset if used properly, although very few companies make VBL clothing.

BTW, the Cuben quilt was overall a good piece for me for almost 10 years until the Cuben started to fray and delaminate. Just had to make sure it matched the conditions and not to rely on any insulated clothing to up my sleeping system.

Nick – very instructive as usual!

It’s obvious now you point it out – the built in VB is surely an issue for any additional layers of clothing.

If the Blue Bolt has enough venting to prevent your clothing getting damp, then it must be thermally inefficient. If not, any layers worn under the built-in VB will surely suffer. Neither really works.

This must apply to the Gryphon product as well.

From memory, Stephenson recommended sleeping naked inside the VB liner of his Warmlite sleep system to get around this issue. But as you say, that assumes enough insulation in the quilt or bag to cope with the lowest temperatures you encounter. Not being able to get nighttime use out of your clothing doesn’t make much sense in the UL world.

I really hadn’t thought this through when I posted…

Obx – thanks for the Stephenson link. Brings back memories.

It really is worth reading for anyone who wants to understand vapour barriers. He sure was an original thinker.

What really surprised me, though, was the picture of their pack-raft. In 1974…

(Tickled that you should think it requires a nudity warning though – you Americans can be quite prudish! In Europe, no one would turn a hair – particularly the Scandis, French, Italians…)

Yeah, if you sleep naked in your sleeping bag then you have to have a warmer, heavier sleeping bag

If you’re minimizing weight, better to wear your VBL and wear your warm clothes over that.

I made a shirt and pants from “fuzzy stuff” which worked, but I never felt it was better than lighter weight material so I stopped using it

But, I wasn’t wearing it in really cold for days – I think a VBL base layer may work best in those conditions

I’ve heard about the naked people catalogs but never bothered to look at it.  Yeah, U.S. people are prudes : )

Okay, I looked at the catalog, thanks

The nakedness was very 1970s.  Gratuitous nakedness that had nothing to do with the product.  Some of those women looked very young, like under 16, is that okay?  Or maybe just anatomy we shouldn’t be worried about?

Funny how there’s good technical information in there.  Pictures of clothing made out of “fuzzy stuff”…

They were a very eccentric family with a strong commitment to nudism in the outdoors.

The catalogue was meant to spread the word about what they saw as a movement.

I agree that nowadays we’d be more careful about picturing young people naked. There was far less awareness of the pernicious extent of child abuse back then.

But there’s a rather beguiling innocence about it all, and not the slightest hint of titillation.

The catalogue is a very interesting record of the period, and some of the ideas are still pretty relevant.

yeah, I agree, no titillation, I guess I should quit being such a prude : )