Sleeping pad systems for bivy sacks

Using a small pad to fit into a bivy is one approach, but isn’t the cause of the problem that bivies are too small?

Wouldn’t a more direct solution be to insist on a bivy that is large enough for a modern sleep system?

I went for an overnight this past weekend and used the following setup: An old Duomid tent (which is basically size of a solomid xl), with a 1/8 pad under a Bristlecone 6′ wide bivy, with my 25″ wide regular length Nemo all season and 68″ wide Tanager inside it. The tent tarp was soaked with condensation and the footbox of my bivy and bag were both wet. I can’t tell if that was because I pressed against the tarp or if the airflow was limited between bag and bivy or both.

I didn’t really have to set up the tent because conditions were good, I was just practicing the combined setup. Now I wonder how wet the bag and/or bivy would have been if outside and exposed.

I guess I just need to just use my 20″ Nemo trail or Therm-a-rest Z-Sol pad for my bivy system and use my 25″ pad for my comfort system with my double wall tent.

Bill – yes, that seems obvious to me as well. We are putting together a market survey of bivy sacks, and it’s shocking to me how few of them accommodate air-inflatable pads that are 3+ inches thick without loft compression of the bag. Or maybe it’s not shocking, and the bivy sack market is just slow to catch up to current trends in pad use.

Looking at bivies, few gave actual widths. Rather they gave the circumference. I think I can understand why, but it does make it a little hard to vision, at least for the novice. I settled on the HMG Splash, partly because they gave me the figures that I wanted. The large is 27″ wide at the head end, tapering down to 20″  and it’s 78″ long. About the same size and taper as my Thermarest mummy pad. With 9″ sidewalls and 28″ high at the head, 21″ at the foot, I still  have the full width while lying on a 3″ pad with room to move my arms and legs. The pad helps the Splash keep its shape. A little more effort I think than a minimalist bivy like the Samaya.

Moving up in size would be the S to S Escapist, though I’m not sure how it’s actually categorized.

Pad(s) outside the bivy is the way I go.  Not a quilt user so the integration with the pad is not an issue.  CCF on the bottom, self inflating on top.

Im heading out in the Adirondack Mountains this week for 2 nights. Will be using my MLD eVent Soul bivy with Nemo Switchback pad.  The pad will be on the ground and my bivy on top of it. I sleep with a quilt. Overnight temps will dip to 30°F,  possibly a few degrees less since will be camping near lakes in the mountains.  Probably will use MLD Spirit 28° quilt.. but contemplating bringing the 20° EE synthetic quilt instead. It will be a last minute decision for me.. but the pad and bivy are no brainer.. or should I use my air pad???

I think at 30F I would start to feel cold if my CCF pad was outside my bivy sack, and right on the edge if it was inside…but wind and ground temp probably play a role as well.

just get a big enough bivy

just get a big enough bivy

Therein lies the heart of the problem – there just aren’t that many out there that can accommodate thick inflatables without compressing the loft of a 3-season bag.

Maybe Dave is thinking of something like this?:

https://bivysack.com/shop/ols/products/bivysack-two-person

EDIT: That should be big enough. Now we just need a WPB top to fit the rest of Ryan’s recent posts on the topic of alpine bivies.

There are larger bivies. They’re called tents.😁

27- 30°f overnight temps. Daytime temps sunny and hi 50s.. these 2 low overnight temps are first time for this fall.. so ground will not really be that cold yet.  I think

Plans changed. Going to the  Catskills for 2 nights, heading up there tomorrow morning.   Overnight Frost warning in affect for Wednesday and Thursday with a low of  28°F..  Winds 6 – 10 mph with gusts to 21 mph.

So 20° quilt its.  “Winter is coming”