Foam To "Upgrade" My Bivy Bag

[DayTrip]

I've become absolutely hooked on bivy camping the past few years and want to "beef up" my set up to be more durable on rough ground and be comfortable in lower temperatures (like down to maybe 10 deg F at worst). I've been using my OR Gore Tex bivy but it was really intended for emergency use and is pretty cramped inside. It only zips through the top too so it is quite awkward to get inside and slide down in it with a z-fold, quilt, etc. without everything getting bunched up. Then you have to toss and turn and yank on stuff to adjust, all while generally on rough ground (generally bare rock or rocks and gravel). I've endured some pretty awesome nights in it but I need to up the comfort and convenience factor.

So I want to start using my Sierra Designs bivy because it zips to the waist on both sides and has a screen window in the face. It is roomier but much thinner than the burly Gore Tex of the OR bivy. The whole bag is the same thickness and material. The traditional z-fold pad slides around because it is smaller than the bag dimensions and in a bivy is quite annoying bunching up and closing on itself. So I'm looking for a material to make a "floor" out of in the exact shape of the bag so there aren't "dead areas" exposed to the ground and more importantly my inflatable pad. I thought it would be pretty easy to find a roll of foam to use but that has proven not to be the case. I wanted a 36in width product (the maximum width of my bag) and at least 90 inches long (for the length). Seems like 25 in is the maximum width for such things and 72 in for a length.

Anyone have thoughts on a floor material that would make sense for this application? Main goal is fully covering the entire floor for puncture protection and some modest padding, not insulative value. Everything I've come across so far is either not available in the dimensions I need, would absorb water and/or is far too heavy to be practical. For any tinkerers out there with some ideas let me know. Thanks in advance.

 

[NHChris]

RidgeRest pads 72 X 20 are available on Amazon. R-2.

 

[Ear Drum]

I've heard good things about the Gossamer Gear thin pads. They were out of stock for a while, but I think you can order one at the moment from Garage Grown Gear, a site specializing in the hiking cottage industry.

https://www.garagegrowngear.com/products/thinlight-foam-pad-1-8-by-gossamer-gear

It's only $22, and you can choose rolled or folded. It looks a bit like a thin yoga mat, but is much lighter weight.

If I may ask, do you also use a tarp over your bivy? What make / model? Thanks. For myself, I like a 1P tent, it's small but roomy enough to move around a bit. Weighs very little and packs down small. I use the REI Quarter Dome 1P - I'd call it semi-free-standing, it's pretty stable with just the poles but does best staked. Works great on a tent platform too.

 

[TEO]

I second the RidgeRest if you want padding. If you get the large, it's 77" x 25". That said, if you have a good pad and it's not winter, a second pad is overkill. Just get a sheet of Tyvek and cut it to size. You can get small pieces sold for tent footprints on Ebay. (When I picked up a Big Agnes tent several years ago from Outdoor Gear Exchange, I learned that OGE doesn't sell tent footprints. They believe that footprints cost too much, and that Tyvek is not only less expensive, but a superior option.)

P.s. Like @Ear Drum, I'm a fan of one-person tents. A good one is marginally heavier than a bivy sack and is still small enough to fit just about anywhere. The extra room is especially nice when you're trying to escape rain or bugs.

 

[DayTrip]

RidgeRest pads 72 X 20 are available on Amazon. R-2.

Looking for 36x90. Was hoping to find a rolled good in a 36 in width but no luck so far. Pads like you reference are readily available but do not meet my needs.

 

[DayTrip]

I've heard good things about the Gossamer Gear thin pads. They were out of stock for a while, but I think you can order one at the moment from Garage Grown Gear, a site specializing in the hiking cottage industry.

https://www.garagegrowngear.com/products/thinlight-foam-pad-1-8-by-gossamer-gear

It's only $22, and you can choose rolled or folded. It looks a bit like a thin yoga mat, but is much lighter weight.

If I may ask, do you also use a tarp over your bivy? What make / model? Thanks. For myself, I like a 1P tent, it's small but roomy enough to move around a bit. Weighs very little and packs down small. I use the REI Quarter Dome 1P - I'd call it semi-free-standing, it's pretty stable with just the poles but does best staked. Works great on a tent platform too.

So for purposes of this post I'm talking above tree line on ledge and/or rocks in the open. Not conventional camping. I've done a ton of experimenting with this and honestly go back and forth with it constantly depending on exactly where I am bivying and what I am expecting for wind. Full disclosure: not all of the places I do this would be considered "legal" camping spots, although I am adamantly LNT so I'm basically sleeping on ledges or rock piles free of vegetation. Judge me how you wish. I've become pretty addicted to the above tree line sunset/moonrise/stars/sunrise experience and choose places to maximize this. I usually have a camera/tripod at the ready and frequently get up to take photos. An example:


For set ups, I have an OR Gore Tex Bivy sack, the Sierra Designs bivy sack mentioned, a cheap bivy shelter I got on Amazon, and a 1P tent I bring without the fly. The cheap bivy shelter I got on Amazon was an awesome and convenient design for a lot of places but the cheap fabric did not breathe at all and when I needed to close the flap for cold or wind and I got soaked and after only a few trips I could see rips already forming. So that one is out. The 1P tent without a fly I really enjoy and it is the most convenient as TEO mentions for bug avoidance, stashing some gear inside of it and an unobstructed view. But it is not very practical for the rugged and uneven terrain I typically set up on. In the right spot though it's my preferred set up. The OR Gore Tex bivy fits the bill for durability and weather protection but it is a huge pain in the ass to get in and out of on rough terrain (on any terrain really). It only zips at the neck line so keeping a z-fold open, sliding inside without disturbing it, etc without messing it all up is near impossible. Then you have to shift and fidget on sharp rocks to get everything situated. It is quite snug. I'm not sure how I haven't popped my inflatable pad yet doing this but I'm sure that won't last.

So....what I want to do is start using the Sierra Designs bivy bag because it has easier in/out access and is roomier for everything but still pretty contained. It is also much thinner. So I want to construct some sort of protective floor to slip in it to replace the z-pad and get much better abrasion and puncture protection). Or alternatively, I'm thinking about making a "reverse quilt" type sleeve of some sort that the bivy and all my stuff would go in (imagine an underquilt for a hammock or the way a quilt attaches to a pad with little straps only upside down so getting into the bivy and sleeping bag is still easy). A padded hammock I threw down like a ground cloth and put my stuff in would be a good visual. Patio furniture covers?? I don't know. I'm currently doing this with a 20 deg quilt but would like to start using a 0 deg sleeping bag for added comfort and to take this set up a little deeper into the off season. In the OR Gore Tex bivy with a 20 deg quilt I've gone into the high 20's very comfortably but stuff like getting up to pee or accessing stuff you put in the bag to stay warm is a most unpleasant process. Pulling a hamstring or other muscle is quite the experience in such a set up....

It's a pretty specific use case I'm trying to tinker with, not a generalized camping set up for all my trips.

 

[Ear Drum]

Thanks for the deets!

 

[DayTrip]

I second the RidgeRest if you want padding. If you get the large, it's 77" x 25".

That name was ringing a bell with me so I Googled. It wasn't what I was thinking. Turns out I own one of these! (My gear buying process is generally buy first and ask questions later). This might be better suited to this application than I realized and it's already paid for so.....

 

[TEO]

Full disclosure: not all of the places I do this would be considered "legal" camping spots, although I am adamantly LNT so I'm basically sleeping on ledges or rock piles free of vegetation. Judge me how you wish.

TMI. There are good reasons why you should only be camping in legal sites and the rules are made for everyone including you, not everyone but you. Second, you compound your infraction by bragging about it online, which only encourages others to feel "special" too and break the rules.

 

[DayTrip]

TMI. There are good reasons why you should only be camping in legal sites and the rules are made for everyone including you, not everyone but you. Second, you compound your infraction by bragging about it online, which only encourages others to feel "special" too and break the rules.

Special? Bragging?? A couple of times a year I like to lay on a pile of rocks, take some pictures and try to get comfortable and rest for 5-6 hours. Not exactly the stuff of legend. I'm not even sure what I'm doing is considered camping. If I did the exact same thing during the day it would be called a nap. Just trying to honestly describe what I was doing for context because initial replies were related to normal camping. But whatever....