Mesh topped bivy under a 5X8 tarp in cold weather?

http://milesgear.com/EBivy.html

Not sure if it will fit a 20 bag and neoair.

Check out the Borah Bivies. He has both bug bivies as well as regular bivies, and can all be had for well under $100.

http://www.borahgear.com/index.html

A TI Goat raven Omni would work with your pad. My setup for this weekend is exactly that, but with an Exped UL7.

I really like the look of the Borah Bivies. I think I'm going to pick up the M50 side zip. Possibly one of their tarps as well instead of the Integral Designs.

Thanks!

If you're used to small tarps then I recommend a poncho/tarp like the 7oz one from golite that will also let you save the weight of rain gear. First time I ever used a poncho/tarp was in the winter with an unexpected 9" of snow. Fell in love with it and used it almost exclusively for a long time (on my solo trips).

Don't see any reason to use a mesh bivy in cold weather. A dwr bivy can cut some wind and add a little warmth, but the mesh wouldn't do a whole lot for that.

-David

Edit: For the record I don't actually recommend poncho/tarps if expecting much snow, other shelter options are much better suited to those conditions… but it was still fun!

+1 for John's excellent work.

I'm actually not used to small tarps at all, and this will be my first tarp experience.

I was drawn to the 5×8 (or Borah 5×9) because they're cheap and very light, but I've been second guessing myself for a little while now. I'm tempted to do the sensible thing and pick up an Oware 8×10 flat tarp and just enjoy the space, but the added cost and weight is sort of disappointing.

I have very little experience with this, and when it all comes down to it, it's for use on a NE trail with shelters so it'll probably see very little use initially.

"I was drawn to the 5×8 (or Borah 5×9) because they're cheap and very light, but I've been second guessing myself for a little while now."

Get an old sheet, cut it to 5×8 or 9, punch small holes in it where guylines would normally go. Set it up in your yard. Crawl under it and lay down.

This will give you a very good idea on whether or not you think a 5×8 or 9 tarp will work for you before you spend any money.

First, I’ll second Borah Gear bivies. I have one and love it. Second, if you decide on an 8×10 flat tarp, check out Etowah Gear here. Cheapest I’ve found them at $75. I haven’t used mine in the field yet but it looks like it’s constructed well.

I"m with Douglas…
You can also get for a few dollars a drop sheet (painters sheet) .
Any tape works with that . Just re-enforce the corners with it .
Franco

I spent some time under a makeshift 5×9 today and played around with pitches. I can certainly see a decent chance of some rain ingress, but I'll be in a bivy.

I also got a PM from a member here and I have a Borah 5×9 on its way for a great deal, so that's sort of a no-brainer.

I think I'll be pretty satisfied with a 5×9 for now (especially since I'm spending much of my time on AT style trails in shelters), and next season I'm considering picking up or making a cuben 8×10 or 7×9.

This is such a weird thing looking back to not too long ago when I would never EVER even remotely consider tarping. I was a pretty firm tent sort of guy. Skin out weight is sub 10 lbs now, and a month ago I was using an Osprey Aether 70L pack. This has been a fun bit of research and planning.

Thanks guys!

I would want a bigger tarp. A workaround might be to use a very thin cloth layer draped over the bivy, maybe using an internal ridge line. If you had enough ventilation to be safe, you could rig a space blanket that way. With cloth, it would barely need to be self supporting with the outer tarp taking the weight and wind force. Kind of a windshirt for your bivy :)

In using a Hennessy hammock, I have been surprised how much the no-see-um mesh slows down air flow. It is definitely warmer with the net zipped closed. There are hammock designs that offer top covers and there is little difference between the top side of a hammock and a net bivy, except for the ridge line. Of course, the concerns are with ventilation and condensation.

The idea of sleeping under a Tarp in weather where the temperature is going to at or near the rating of your sleeping bag doesn't seem smart to me. A 5 by 9 tarp will provide minimal heat retention, the Bivy will provide some.

Have you slept in a 20 degree bag outside of a tent in 20 degree weather before? That seems like a something I would want to have had experience with before committing to a 25 day trip. If you are legitimately expecting 15-25 degree lows I would think a zero degree bag would be more like it.

I do plan on a couple nights out in the coldest weather I can manage (Ohio is unfortunately not as cold as vermont quite as early). I don't have any experience at all outside of a tent, so I'm in completely new territory here.

The bag is going to be a Zpacks 20 degree (which seem to be quite true to rating), although the 10 degree version (warmest they make) isn't very much more at all and is probably quite a good idea.
I'll also have a good midweight baselayer top and bottom and a primaloft top to help along.

The Long Trail in October supposedly has an overall average low of 31, but I've been told several times to fully expect a couple of 15-20 degree nights. Even then, like I said, the tarp system is mostly for a contingency plan on case a shelter is full or I overstretch/understretch my mileage. Most people seem to finish the trail having only set up their shelter once or twice.

I can't imagine an AT style shelter is much better in terms of trapping heat, though.

I just hiked the LT southbound in July, so here's my experience:

1. For the entire length of the LT, I never used my tent, except the night after I finished in MA. Shelters are plentiful, with the farthest distance being about 8 miles apart. In one place, there are 3 shelters within 6 miles. In October, they will also not be crowded by groups, which was the reason I carried a tent with me (and almost needed it twice).
My point is, you actually don't need a shelter at all–although you might want to carry one for security and flexibility (I liked having the option of camping anywhere, although I didn't ever do so).

2. Bugs will almost certainly not be an issue. They never bothered me in July, so why would they be around in October?

3. Unless you're very careful about where you camp, there'll be some cold nights. I'm talking not only 15 degrees, but also windchill because there are a ton of shelters at high (for VT) elevations. The shelters on Mansfield (Taft and Butler) are 4 walled, but the ridgeline to the North (Sterling Pond and Whiteface) is very exposed and the shelters are 3 walled. The secret here is that the 4 walled ski hut is unlocked, and very warm. I slept in the hut and was much warmer than those who slept in the Sterling Pond shelter, who set up their tents inside the shelter to endure sub-40 degree temperatures chilled further by high winds (this was in the midst of the hottest July on record).

4. Having grown up on the VT/NH border, I will also tell you that we have often had snow days (school closed) before Halloween. Never more than 2-3 inches, but it's something to be prepared for.

I would seriously recommend a lower rated sleeping bag or a liner. When you're out there for that length of time, the warmth is well worth the weight.

If you have any more questions about the trail or general October VT weather, I'm a resource.

Thanks! It's fantastic to get some more insight into the LT. I'd certainly make a lot more mistakes if I didn't get good advice like this.

The more I think about it, a 20 degree bag certainly sounds like it's pushing it inside shelters, but does a true 10 degree bag (in a bivy if necessary to block some wind) sound like a fairly safe bet? I'm not opposed to a silk liner, either.

My main attraction to the zpacks bags is the impressive weight and I like headless bags quite a bit, but their warmest is the 10 degree bag. Price isn't bad at all, too.

I like the bivy+tarp option for a carried backup shelter because it's simply the lightest thing I can find for under $200.

I just went NOBO in August and agree with Nick.

The way to tell what shelters are what is to look at the LT map. the larger icon usually means 4 walls and usually called Lodges or Camps. Except Bear Hollow shelter is also 4 walls. Also the Stark's Nest on Mad River Glen and the ski lodge on top of Bromley will be open.

being able to use the bivy in the shelters to add warmth will help. also you can put the tarp up across the front if you have to stay at 3 sided (more common down south)

have fun.. the foliage should be popping by then.