Bivys and tarps

Alright let me try to answer:
"if i buy a bivy would i need a tarp? wouldn't a bivy protect you from the elements to a degree."
There are waterproof bivys and then threre are water resistent bivys. A water proof bivy will allow you skip the tarp but you will have no room to cook and sit up because you will need to be zipped up in your bag during a storm. I think most waterproof bivy users are alpinist who need a small shelter most likly to be used in a snow shelter or somthing like that as is the origin of the bivy.

"Also if i buy a tarp do i need a bivy? A tarp protects you from rain, so couldn't i just buy a small mosquito net for the head of the sleeping bag?"

In the begining people used larger tarps with good coverage something like 8×10 was standard tarper size. You didnt need a bivy as the margin around you was large enough to keep splashback and windblown rain away from you and your bag and yes, all you needed was a headnet or just hang some netting from underneath. As people tried to go with smaller sized tarps to reduce weight, reduce the space requierments for camp, and to reduce the amount of surface for wind to catch ( i.e. more storm worthieness) they found the need to protect themselves from splashback and wind blown rain as now there is less of a margin around them. The breathable/water resistent bivy was the answer. It protects from accational rain blown under the tarp, it adds warmth, it adds bug protection, it has as small of a footprint as can be had on the ground, and the small tarp gives room to cook, sit up a bit and do other things during a storm while in your bivy. It also allows you to skip the tarp set-up if you are confident it will not rain during the night making camp set-up and break-down a breeze. I have tried a lot of different tarp-tents and tents and I still preffer the bivy/tarp setup over all others.

Depends on mood, weather, taste, and what one is comfortable with.

Bivy only is great for most conditions (including storms, but it really sucks to be stuck in the bivy for long storms…)Great for no fuss and go trips!

Tarp only is great for most conditions (really pretty awesome, the mosquito net is a sanity-saver)

A tarp + water-resistant bivy is great in situations where the moisture /condensation in the air might be present (eg fog, foggy rain). Also the bivy can add that needed protection from the wind and side spray.

I would say try all 3 set-ups and see which works best for you!

Note: In general I prefer tarp only for most of my
backpacking trips.
Bivy only for climbing trips or high mileage trips
Tarp + Bivy for trips where I 'know' the weather will
be temperamental.

Well i can see the benefits of using just one , but i see why u could need both. My trip this summer is going to be in august and we are hiking from Tuolume meadows, to mammoth on the pct, and than a loop back into Yosemite. All in all it is going to be about 10 days and for the most part high elevation. So in high elevation that means just a tarp would probably be fine right?

Ya, Nat is right- the set up needs to match the enviroment. If I undersatand correctly in the Sierras it dosnt rain that much and when it does it is usually a passing storm? Im planning a JMT hike this aug/sept as well.
My point of view comes from living in New England where it can rain most anytime and it can rain hard for days if not weeks without letting up.

August 2008 Tuolumne Meadows to Mammoth (Reds Meadow). Always major mosquitoes that time of year (even more with all this snow/rain we’ve had).

Might I suggest a two person tarp such as the Gossamer Gear SpinnTwin tarp or the MLD Grace Duo Spinntex ( both large enough so you wouldn’t need a bivy) and also the BPL Simblissity Inner Peace Noseeum Bug Tent to keep the pest at bay.

Or you might consider the Gossamer Gear Squall Classic Tarptent at a 1.5lbs it includes a floor and bug netting.

Or if going solo the Gossamer Gear "The One" includes a floor and bug netting at 1lb.

I have been thinking about the combination of the two of a bivy + tarp. I have been looking at a tarp that ties all the way down to the bottom so that would stop any rain from splashing in for the most part. The top and bottom though would still be vulnerable. Anyways though how would a tarp + synthetic water resistant sleeping bag do? has anyone tried this combination? thanks again

andrew

I use that combination quite often. No bivy, just a 1.5 oz. polycryo ground sheet from Gossamer Gear. A head net works OK for me when the mosquitoes are few. When mosquitoes are heavy, I add an A-16 bug bivy. What kind of tarp are you considering?

thats what i always use and its great. I often use a 5×9 tarp with it, although I have been switching back to my 7×10 in the colder months because of the increased wind resistance of staking it to the ground. I may stick with it until early summer before I switch back. I have never had any issues at all with the big tarp which is why I consider a bivy unnecessary out of heavy bug country (which im never in!!!) and just another gadgety expense that adds a half pound to my pack.

For a while i was mainly looking into quilts and down sleeping bags. It was not until recent i thought of just going with synthetic and a tarp. So i have not thought much yet about that. I have only looked at one which was the Atom 40. It got some good reviews but i will have to do a lot more research still. If you guys have any suggestions i will greatly appreciate them. thanks

andrew

I don't tend to use a bivy with a tarp. I just use a groundsheet. Sometimes I don't even bother with a tarp.

Yesterday I was camping out in the garden – a Snowline 750 bag on a foam mat and groundsheet. Night temperatures were close to freezing and it was a clear still night. When I woke up there was some condensation/dew on the outside of the bag near the feet but the bag was warm and dry for me.

A little bit of sunshine and the bag was good to go.

A bivy is used under a tarp because the sleeping bag used cannot cope with the conditions. That's all.

A synthetic bag with a DWR or pertex outer will cope very well with most under-tarp conditions and most outdoor dry conditions.

There's no point in buying an ultralight bag if you then have to gift-wrap it in a 'heavy' bivy bag just to use it…

In 2006/7 most of my tarp camping was done with a synthetic bag under just a tarp in all sorts of wet conditions. It was just fine.

This year I've moved over to ultralight down and it does seem to need a little more protection. The DWR-only coating doesn't seem to be quite enough for use under just a tarp – but I'm still testing. I'm trying a number of different scenarios – eg tarp, tarp+bivy and so on and seeing just how much moisture a bag absorbs.

It's not very scientific but I'm jus trying to work out what goes on. The base-line for me was a down bag inside a twin-skin tent where the weight-gain overnight was 50g on a night that was moist but not warm with the chosen bag.

At the other extreme, a fully waterproof bivy bag used with a down sleeping bag had a weight gain of around 100g for one night.

I've yet to get numbers for use with a pertex or DWR bivy bags or a bag under just a tarp – I have a day job…

What I'm trying to do is work out what setup is going to be most resilient for the cold-damp conditions that are typical. I'm interested in the total weight of everything together that provides warmth and shelter at night.

There is no greater pleasure than sleeping under nothing but a tarp in the summer. But, Conditions dont always allow for it.
People are making good points about a synthetics ability to withstand some wind blown rain. But, that is not the only reason you should consider wether to use a bivy or not.
1. How are the bugs in the area you are planning to camp?
Are they flying, crawling, or both ( mosquitos and fire ants?). This will answer whether you need a fully or parially enclosed bug shelter. Or none at all.
a). What is your tolorance for bugs?
If you can sleep like a baby while a mosquito munches on your forehead- good for you! Grab a head net and go to town! If you lose sleep, you need protection.
2. Do you use a mummy bag or a quilt?
A bivy works well with a quilt for a few resons:
a) It eliminates chilling drafts. It adds a bit of warmth especialy in the shoulder seasons.
b) It helps keep the quilt in place especialy if you tend to shift around at night. This one is admittedly not that big a problem, but quilts go great paired with one.
3. Momentum is .9 oz. a square yard – nanoseeum is .7 oz.
so you arnt saving a lot of weight going with a fully enclosed bug-net shelter over a vapour bivy,and a vapour bivy gives more bang for the buck (see 1. and 2. )
4. Then there is personal preference and it cant be qualified. Mabey you just hate being in a bivy or mabey you feel like its a protective coocoon. Only experience will tell.

Headed out to Tuolumne, Yos high country and the likes in August?! Good choice!

A tarp will be fine for August, the storms, though intense, are pretty short.

A tarp and synthetic bag works great too.

I usually head out to that area every August, and most of the time the tarp stays in my pack, but not my bug net!!!

Tarp wise a 6 x 8 Integral Designs tarp has worked wonderfully.

If I go with a friend then we use her Kelty Noah 10 x 10 tarp (i think?) and that has held out fine.

Have fun, and bring a bear bucket.

I have never been up there in august, or let alone ever walked from tuolo to reds meadow. So from all the responses i am going to have to guess all the high elevation lakes are mosquito infested that late? Do you guys think i will have any water problems or will they be plentiful? Do you guys think i will need to bring bug spray even for the day? Thanks again

andrew

nice, nice stretch

lots of water, but it will be hot in day & depending on the strategery of your water refueling, there could be some stretches that seem long without (i'm thinking 3/4 way up donahughe to bottom of canyon afterwards & from there to 1000 island lake

i would assume mosquitoes & be thrilled if they weren't a factor

Andrew that section of the PCT from Tuolmne Meadows down to Mammoth is awesome. One thing you might want to change if you can. Once you get to 1000 Island Lake, you can go around the lake at the base of Banner/Ritter. Head south over the pass to Garnett lake, following cross country you can go over the next pass to Ediza and to Reds Meadow on trail. This makes the hike very interesting and fun. You can touch the mountains as you hike by. Great views of the Minarets are there for the taking too. Both passes are easy, class two.

Thanks again and yeah i am really excited about the trip. I actually will be coming from reds meadow from the other way. We will be hiking down the JMT to merced lake from tuolo meadows. Than from merced lake we will be hiking up to Joe Crane lake at the peak of Yosemite mountain border. Than hike down the isberg trail, to the stevenson and last of all we will take iron creek to reds meadow. than hike from reds back up to tuolo. This is the map i have been using to map out what i have done. if you guys know a better map thanks. I have found this one useful though because it shows all bear canister requirements.

http://www.nps.gov/seki/planyourvisit/upload/SierraNevadaFoodStorage.pdf

p.s. we mainly added on more because from tuolo to reds was not enough mileage. We were wanting about 100 miles and the loop i made on that map is about 100 or a little more.