Please convince me that a Duomid tarp plus bivy is good!

[Andrew B]

OK, I’m on the verge of purchasing shelter and quilt. Wondering if anyone can at least tell me I’m going in the right direction. First of all, I live in the Pacific NW so rain is a significant issue. I like Plan A (below) but the worrier in me is suggesting Plan B.

Plan A –

• Down Quilt (20 degrees) probably the Enlightened Equipment one
• MLD Superlight Solo Bivy
• MLD Duomid (Silynylon)

I’ve always wanted a bivy sack and love sleeping in the open, so I’m excited about this option. I’m going for the Duomid for that little extra coverage, and also to be able to accommodate another person if needed. My only hesitation is the openness to the elements. I’ve used tarps (or no shelter) in the southwest US and during summers, here. But I’ll be using this set-up in the Spring and Fall in the NW and can expect heavy rain. I have an image of water running under the tarp, or rain spraying under the edge, and soaking my gear in the night. Most of the photos I’ve seen of the pyramid shelters are in clear weather, not in a boggy Olympic rain forest, for example. All this leads me to consider:

Plan B –

• Same Quilt
• No bivy
• TarpTent Notch

This seems safer, water-wise, but also small and not as versatile. And I really want a bivy. Any thoughts? Anyone out there use a pyramid shelter in wet conditions, spring and fall?

Final, bonus aesthetic question: I like the orange Duomid. Is there any practical reason why I should get the darker grey or green? The only think I can imagine is wanting to be unobtrusive or unnoticed, if I’m sleeping somewhere off the beaten path; or trying to survive and avoid detection in a postapocalyptic scenerio, in which case I’d be kicking myself for not getting green.

Thanks in advance for any input!

[Paul S.]

The DuoMid will provide better coverage from the rain since it’s quite a bit larger and you can pitch it all the way down to the ground if necessary.  You don’t really need a bivy for rain when you’re under a mid-style tarp.  I would be worried about condensation in those conditions.

[Link .]

Here are some good articles for you to read

. The Bivy Condensation Conundrum .

. Dew, Frost, Condensation, and Radiation .

. CONDENSATION IN SINGLE-WALLED SHELTERS: CONTRIBUTING FACTORS AND TIPS FOR REDUCTION .

.  STAYING DRY IN A BIVY SACK: TECHNIQUES FOR MANAGING THE MOISTURE BALANCE BETWEEN EXTERNAL PRECIPITATION AND INTERNAL CONDENSATION .

. NIGHT TIME CONDENSATION ON TARP AND TENT FABRICS .

I own the bivy you are looking at and prefer my ENLIGHTENED EQUIPMENT RECON BIVY MLD started making a SIMILAR ONE or even a Sea to Summit Nano Mosquito Pyramid  which is floorless and weighs 2.9oz for the single and is only $49.95 in buggy warm conditions otherwise no bivy, a lot depends on site selection and how many people are going to be inside your Duomid? I live in the NW and would not hesitate using a Duomid in the rain with a polycryo ground sheet or a Bathtub Groundsheet / Tent Floor .

[Brad Rogers]

Perhaps not in the rain but we got plenty of rain at night.   The Duomid is really wide for one so splash shouldn’t be a problem (ends can be pitched to the ground).  On the flip side it is tight for two or at least seems like it would be (never tried it).

I am not sure the bivy is necessary except for bugs but I have never backpacked in th PNW though it rains as much here in the SE and I have done 2- 2 week trips to AK.

The Duomid is a solid shelter and is probably more versatile than the notch.

[Link .]

I prefer stealth colors over bright colors unless you are worried about hunters?

[Alex Wallace]

I like plan A, but possibly add an inner as an option.

I’ve been pretty happy using a TiGoat Bug Net Bivy & DuoMid, but I’m in a much drier area than you (north to central Sierra). I prefer to sleep under the stars so I’m usually just in the bivy, but will setup the DuoMid if winds and/or rain are likely.

I have weathered a few intense rain storms w/ the DuoMid, but they’ve all been over by morning. During those storms the DuoMid offered plenty of protection, but I did deal with serious groundwater pooling once. Even though the bivy has a bathtub design I was too worried to test it out and put away my sleep system and crouched for two hours till the water dissipated. Long night.

Since then I started using the net inner w/ bathtub floor when big rains are expected to give me that extra space and protection from ground level water. Of course since I started doing this it hasn’t been necessary, but I’m sticking with it if the forecast calls for rain since I’m not too worried about the 3 ounce weight penalty over the bivy.

As for color, I previously owned a yellow DuoMid and really liked how it look, but sold it to buy a different color because it seemed like the yellow attracted mosquitoes.

 

[Lester Moore]

June -through mid September in the PNW – you could safely use a Duomid, a 1 ounce piece of polycro and a 3 ounce STS Nano Pyramid Mosquito Net just fine. Cinch down the Mosquito Net draw cord and the edges fit snugly under the perimeter of a full-length air mattress really well. Lighter, more affordable and easier to deal with (no zipper) than a full inner net or bivy sack.

I love my TT Notch, but in the PNW summer I have had no issues with a Deschutes CF tarp and light mosquito net. No plans to use the Notch again any time soon, especially with a bivy under the Deschutes for shoulder season.

In the Fall, add in the Bivy sack and a VBL under that Duomid and you’ll be pretty bombproof during the PNW shoulder season (fog, cold wind, heavy rain, etc).

[Katherine .]

I love my MLD bivy, but I love it more outside the PNW.

I have more gear than actual experience (hammock kit; Locus Gear ‘mid; TarpTent statospire for trips w/kids), but the *one* time I used the bivy + hammock tarp in the PNW, I experienced condensation inside the bivy.

I very much liked using the MLD bivy in Utah and am looking forward to using in the Sierra.

I found I brushed up a lot against a ‘mid. Granted the Locus Gear Khufu is a hair smaller than the Doumid. When I was doing the Wonderland Trail I was wishing I had a Zpacks Duplex instead of ‘mid + inner net. I got the mid cause I thought it would be best above treeline, cause I’m mainly hammocking when there are ample trees.

But at the end of the day I also say: get what you have you’re heart set on. If I were gonna do a redo on my bivy purchase I’d look at one of those new part solid/part mesh topped ones.

 

[Brad P]

A bivy is too confining to me, but you’re not me.  HYOY and do what makes you happy.  I prefer an innernet as my fortress of solitude.  I like being able to sit up and move around in it.  I hope you find the option that makes you happiest.

[Franco Darioli]

Bugs make the difference for me.

We have here, in Australia , a lot of bugs, ants (biting ants) are the most common  but when out horse flies do a better job.

So because at times I like to be out of the bugs and to read I prefer an inner where I can sit up and move around over a bivy.

 

[Chris F]

Just did 9 days in Glacier Bay AK with a MLD solomid and a BPWD inner w/ a cuben floor. Needless to say I had some sort of rain and wind everyday plus tons of bugs when the wind wasn’t blowing. Never had a problem with any leaks at all. My friend even broke my zipper on the mid and I was able to snap it closed with the extra buttons and buckle with no leaks. Only complaint was I wish I had a duo so I could store all the extra paddling gear I had.

[Cameron M]

Slight drift here, but concerning the use of a nano net: I threw together my Deschutes CF with a nano net and found that the single version of the net is both not tall enough for me and is also not a symmetrical pyramid, it is thrown off to one side, making it even less desirable. I swapped it for the double nano version, which is larger in all directions, and it was good enough and still a very light total package.

[Matthew / BPL]

One more data point: I loved my Notch in every way other than the 16″ poles at both ends. I found the shape to be a pain to pack in a small, frameless pack like a Kumo or Burn.

I’m currently using a Superlight bivy which I really like in AZ and Sierra. I pair that with  a Duomid if I’m going with my son. Otherwise I might use my Deschutes or my SLD 5×9 flat tarp. I like the modular approach and the simplicity of just using the bivy sans tarp if it’s not going to rain. I have an MLD Solomid XL inner as well but I haven’t taken that on a trip yet because it starts to get bulky/heavy

I picked up the Duomid on Gearswap in orange and I like the color but I’d probably get it in grey if I was ordering one new.

[Andrew B]

Hey all, thanks so much for the great responses. I just got back into town and read them all carefully. My mind is somewhat blown with regard to bivies – I realize that I should seriously consider a bug bivy plus maybe a ground sheet (bathtub shape), at least for a good portion of the year. That would take care of the bug concern; and allow me to sleep cowboy style when there’s no rain; prevent condensation inside my bag. I think I was holding on to the waterproof bivy concept because I wanted an added layer of psychological security. But I think it would feel too confining and if I have a warm enough bag, I shouldn’t need the extra warmth.  I may still get a full bivy for colder part of the year, but I’m going to start with a bug bivy and see how that goes.

As far as tarps, I’m going with the duomid – thanks for the confirmation that it’s a good one (although Lester’s post made me almost go for the Deschutes, which looks pretty nice.) As far as color, I think I’ll go with grey or green. Thanks again – I’ll report back when I’ve tried out this system in the woods –

• AB

[Brad P]

I hope it works out great for you.

[Matthew / BPL]

Ok, one thought about bug bivies:

I have not had good experiences with my MLD Bug Bivy in my Deschutes. I’ve not tried it in my Duomid. It needs to be pulled up past the top of your head in order to get it to pitch nicely. I’d recommend a Borah Gear bug bivy for use inside a Duomid.

[Andrew B]

Matthew – thanks, I will look into that. You’d think that MLD bug bivy would work with the MLD duomid though, since they are both MLD? Definitely want the mesh to clear my face well. Will check out the Borah one.

[Lester Moore]

+1 on Matthew’s comments about bug bivy sacks and mids. Any bug bivy or net tent that requires upward or outward tension on the head and/or foot of the bivy (i.e. the MLD Bug Bivy) will fit much better under a flat tarp than under a mid style shelter (duomid, deschutes, hexamid, etc). Even the EE Recon, that is less tall than the MLD Bug Bivy, fit’s poorly under a Deschutes if you’re trying to get the netting off your face by using the bivy’s guyline. The ridgeline needs to be taught and under tension for the best fit with a net tent or bug bivy, otherwise, it will sag and droop.

For a taught net or bivy under a mid that has substantial volume inside, the best shape is a pyramid-shaped net tent. Unfortunately, none of the cottage manufacturers seems able to make these for less than 11 ounces. It’s a shame, because something identical to the SMD Serenity Net Tent could be made at 7 ounces using 0.93 oz Silpoly for the bathtub, 0.5 oz NS50 netting and a light 10d DWR material for head, foot and/or side extension panels.

[Matthew / BPL]

fwiw I have an all net hood on my MLD Superlight bivy which is a good option as well. That said, If I had it to do over again, I might ask MLD if they were willing to move the seam between the net and ripstop down towards my feet by a couple inches. I often put a couple things inside my bivy around my head (like a fleece/puffy/pants) which pushes my mouth below the ripstop. Or maybe I just like to nestle down into my bivy more than they expect…

While we are talking about the MLD Bug Bivy, it is a thing of beauty under flat tarp and I suspect I would love it even more in a Grace or Patrol tarp.

[Bob Moulder]

I’ve used the MLD bug bivy under a HMG echo ii (very similar to Grace) for a few nights and it is indeed an excellent combo IMO. I stuck on a couple of the Zpacks loop patches on the underside of the tarp and used some 1.5mm bungee to suspend the head and foot, with a couple of mitten hooks with gates cut off to make things easier.

I don’t have a ton of bivy experience but I’ve had enough to know that I greatly prefer a center zip vs an across-the-chest zip.

[Matthew / BPL]

Yes agreed the center zip is nice although it’s not a deal breaker for me. I might prefer ZPacks bivy over the Superlight but I’m not interested in a Cuben floor.

[Matthew / BPL]

Interesting to note ZPacks is not selling their bivy currently pending a fall design update.

[Andrew B]

For the sake of closure: I ended up ordering the MLD Duomid (grey) plus the EE Recon bug bivy. I decided to go with the Recon over the MLD bug bivy just because it looks like the closed (non-mesh) bottom might offer a bit more warmth. I saw some comments about the Recon not connecting to the Duomid in a convenient way, but I’m hoping that that won’t be too big of a deal. I’m excited to try them out when they arrive in October! Thanks again for all the advice.

[Matthew / BPL]

Please report back about how they fit once you get them in.

[Geoff Caplan]

Late to the party, but I’ve gradually simplified till I’ve ended up with this arrangement in my mid:

1. A robust emergency blanket (SOL) with some DIY tie-outs
2. A DIY floorless, zipless bug net in the Sea-To-Summit nano style.

Advantages:

1. Because it’s not sewn into a complex bivy, you can use a very light ground sheet and not worry about durability – it’s cheap and easy to replace.
2. As a Brit I camp in some very wet places, but I’ve stopped worrying about the need for a bathtub. First, I’m picky about choosing well-drained sites. And secondly, if water does start to flow I simply prop up a side of the groundsheet with pegs, stones, sticks, shoes or whatever’s to hand. Never had an issue even in monsoon conditions.
3. With a floorless bug net, I can pull back the ground sheet and cook inside the shelter while still protected from bugs. Also, you can go for the lightest possible fabric without worrying about durability because like the groundsheet it’s stand-alone and easy to replace.

I don’t cowboy camp much, given where I live. But it would be easy to set up the groundsheet and net for full protection with a walking pole and some pegs and line.

So, very flexible (you can leave the net at home if not needed). Very cheap. Very light, at 150 grams all-in. And so far, has met all my needs.

[Author]

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