Seeking guidance on 2 person bivy purchase

Well, I mentioned I’m a first time poster. Let’s try that again w/o those HTML tags…

I’m considering the purchase of a 2 person bivy.

Context:

• The primary goal w/ the bivy is cowboy camping in areas where rain at night is rare.
• Reasons for going bivy
  • Keep critters out
  • Keep sleeping bags dry
  • Block some wind
  • Splash protection under tarp (when tarp is needed)
• Conditions/Locale: Joshua Tree, Anza Borrego, Grand Canyon, and Zion, but I could also see us taking this out in the Sierras or San Gabriels as well. Point though, rain at night is very low risk where we go. No snow.
• I’ll pitch a tarp when rain threatens (likely an 8.6 x 10 flat) but again, the goal is definitely to avoid setting up the tarp whenever possible.
• When conditions favor a tent, we’ll leave the bivy and take the Duplex.
• I’m 5’8″, 180lbs, and I toss-n-turn.
• Little Lady is 5′, 105lbs, and sleeps like a sack of potatoes, even when I don’t.
• Neither of us have ever spent a night in a bivy, much less a 2 person one.
• Looking at the MLD Superlight Duo Bivy, or something like it.

Pics/Videos
I couldn’t find any pictures of the MLD duo bivy (product page shows the single person bivy), and the only pics of other 2 person bivies I found were empty/unoccupied.  If you have any pics or vids, I’d love to see them!

Size
I pinned a blanket to match the dimensions of the MLD duo bivy (105″ girth), and it seemed a little snug, especially w/ our poofy quilts. Any anecdotal sizing feedback on this from folks who have actually spent some nights in a 2 person bivy?

Condensation
Given our target conditions, how bad should we expect this to get?

Temp Control / Overheating
How does one deal w/ getting too hot in a bivy? Seems like ability to control the temp is limited.

All input appreciated. If you spent a night in a 2 person bivy then I’d love to hear about it :)

I know this was a lot… Thanks in advance!
Bob

Quoting myself from another thread:

I used the SOL Escape Bivvy, 8.4 ounces, as my primary shelter on Adak this July.  48F and blowing at night, low cloud ceilings (so very high %RH), and it drizzled a little bit at night.  For one night out, with a 30F down quilt on a 48″ pad, it was fine.  I was warm enough with a fleece beanie hat on and could have tucked the bivy tighter around my face.  But my down quilt was definitely wetted out a bit after one night.  Maybe okay for another such night, but it would have only been viable for multi-night trips if you had a chance to air out your quilt/bag in the sun, during the day.

It gave me a lot of peace of mind knowing that I could bivouac almost anywhere should the weather turn, my ankle turn, or the visibility disappear.  Now that I’ve successfully used it overnight, it will give me even more peace of mind.

Almost anywhere else, I could have camped under a tree for more protection from rain and radiant heat loss, but Adak is treeless and usually windy.  So we were completely in the open (and because we wanted to notice if any caribou walked anywhere nearby).  In most places, “48F, blowing, and high RH” could have mitigated more with good site selection.

There was enough room inside for me (6’0″, 185 lbs), an inflatable sleeping pad and my down quilt.  I couldn’t bring my knees up very much, but I could turn over and around and it surprised me how well my down quilt stayed in place, above me, where it belongs.

Given the locations and expected weather, I would expect most of the time you would be using the bivy as a ground cloth and just sleeping on top of it. I see no benefit of a 2P bivy. In fact, a 2P bivy seems to mitigate many of the benefits of a bivy. Namely, when on a warm night with no bugs you just sleep on top of it. When it gets colder, you slip inside the bivy, etc etc

I see no benefit of a 2P bivy. In fact, a 2P bivy seems to mitigate many of the benefits of a bivy.

I agree. I’d get a light 2 person shelter, not a bivy.

I see no benefit of a 2P bivy. In fact, a 2P bivy seems to mitigate many of the benefits of a bivy.

I also agree. I used a (heavy duty) bivy for many years, and I always appreciated the flexibility of sleeping anywhere coupled with its durability and weather-proofness.

But I’d never consider using it with my spouse.

If bugs are the only issue, then I’d use a 2p mosquito net under a tarp. And mosquito netting still offers a little bit of splash protection when under a tarp, in my experience.

I 100% get why you’d want a bivy over a shelter. The ease of use and bug protection is great. That said, I have no experience with 2P models. I own both MLD and Borah splash bivies and they are both very nice. My recommendation is decide what you want and contact Borah to see if they will make it for you.

Temp control: if I get to warm I push my quilt to the side.

Condesnation: this has not been a problem in AZ or the Sierra for me except once when I burrowed far down into my bivy. I try not to do that now. I wish the all mesh hood of my MLD Superlight Bivy came down an inch or two farther. I do end up with my nose near the ripstop if I don’t pay close attention. The mesh goes a little farther down on my son’s Borah.

I made a 2P bivy to go with our 2P quilt, and my wife and I are very happy with it (see my myog post), although so far we haven’t used it that much.

To avoid condensation I made the top mostly of netting, with a full bathtub floor (need four small skewer stakes to erect the bathtub, we don’t do that very often) and a top perimeter of uncoated nylon to  enhance draft protection.  We’ve used it in 15 degF in an ADK leanto up to around 60 degF, no condensation.  Haven’t used it on snow yet, though.

I think it’s a tad too large at (finished) 60″ wide x 94″ long with 5.5″ bathtub sides, if I made another I’d likely decrease the width and possibly the length by 5″ or possibly as much as 10″.  But the large width allows us to store lots of stuff inside the bivy…unused clothes, packs (if dry), etc.

Thanks for the posts so far everybody.

It seems like most folks view bivies as a compromise of some sort, but our motivation is to have full view of the night sky with minimal setup and full critter protection while still being able to cuddle.

We have a Duplex as our goto shelter so I get why folks are recommending the tent (we love our duplex), but the bivy is all about the critter-free stargazing cuddle fest :)

I’m curious about why folks are recommending against a 2 person bivy specifically. Is it weight, functionality, do 2 person bivies have down sides that single person bivies do not, something else?

Still hoping someone can share pics of their MLD Duo Bivy or Oware 2p w/ them in it. I’d love to see those suckers in action.

As an old [ and Ex]climber I see huge advantages in a 2-P bivvy but for me a bivvy means a full coverage WPB sack which is weatherproof/storm proof and I think you are after something a little less specialised but I can see no problems with using a sleeping bag cover that is that big, a good way to keep the sleeping gear clean and the breeze off.

Have you considered something like the Fly Creek 2, using just the inner for critter protection?  I love star watching with my Fly Creek, and the fly is very easy to toss over the inner if a small amount of rain comes in the night.  As someone who spent a fair number of nights in a bivy, I appreciate that the Fly Creek inner offers so much more comfort than my single bivy, at about the same weight as my OR bivy.

Renais

Thanks for the info everybody.

> Have you considered something like the Fly Creek 2

Yup. We own that tent – it’s our “guest tent”, but we’re looking for something more open for desert stargazing.

I just placed an order for a borah bivy w/ a full mesh hood. Time to just get out there and see how it goes :)

1. Borah gear 2 person bug bivy. Bring a tarp in case it rains.