When people talk about using a bivvy bag as their sole means of shelter, I'm often the one that'll pipe up and say how miserable an experience it can be if you're already wet or if it starts to rain. Recently, I've been thinking about what would be required to make a 'bivvy only' approach more practical. Obviously the answer is a tarp but how much or little would be required?

I figured that it needed to be light and to pack small. There had to be enough coverage to enable you to get in and out of your bag under cover. Ideally it would allow you to 'cook' and provide shelter for your gear if required. I also wanted something that was very fast to set up, didn't require any faffing about with bikes / wheels to hold it up and could be set-up by anyone, even those 'tarp phobic' amongst us.

Anyway, this is it. As a complete shelter inc' Spinnaker tarp, Dymeena lines, carbon pole and pegs it weighs just a whisker under 180g and I reckon I can possibly reduce that a little more yet. It sets up with just 4 pegs and takes about 30 seconds. It'll cover one person from the thighs up and allow room to cook or cover the top half of two good friends. The entire thing inc' the pole fits in the palm of your hand.

That's basically how I use my Siltarp 1. I've looked at smaller versions as much of the length of mine is wasted when in use and I also need to use a lifter to get the required height above my head.

I guess longer/more coverage has advantages when it's very wet as less of the bivvy bag wets out and it remains more breathable.

Very interested in this though. Can you do it in olive?

I guess longer/more coverage has advantages when it's very wet as less of the bivvy bag wets out and it remains more breathable.

Absolutely, this is an exercise in 'what can I get away with' and is intended to bridge the gap between larger tarp and bivvy only.

Can you do it in olive?

Spinnaker of this weight isn't available in many colours and nothing overly stealth. I had figured that blue would hopefully blend into the night quite well ... I won't say no but it's reasonably unlikely Colin.

Interesting... Been toying with a few ideas for shelter on the TA next year. The Rab Ascent should be waterproof enough and will keep the sandflies out, but as you mentioned, could be a bit grim by itself for 10-30 nights.

Bob from backpackinglight.co.uk used to sell a very similar tarp for just this purpose

This one.

http://www.backpackinglight.co.uk/tarps ... WE102.html

Yep, that's the one

Reminds me of mine (and Sean's). Just updated the thread here: http://bearbonesbikepacking.co.uk/phpBB ... =13&t=8089

I wondered what you were going to make with that material. I guess there's the answer. What's the HH on it? Or is it fully waterproof? I figured you were going to make a gilet from it.

Greetz

S.

I've no HH figures for it Scott but it appears to behave like cuben with regard to water but also seems more abrasion resistant too but is easier to sew although it won't 'hold a fold' like cuben.