British Army Bivy and Groundsheet, Yes or No?

[Jaan]

Good evening,

Many bivy bag choice topics here and I've read through most of them, but haven't found one which discusses groundsheets exclusively.

Having bought a brand new British Army bivy which I received today I have two very simple questions:

1. Do you use a groundsheet with your army bivy?
2. Is it good for extra protection or is it just unrequired extra weight?

All opinions welcome! Thanks!

[Twodogs]

I just use a roll mat under mine when I use a bivi bag
protects the bag and give insulation
Twodogs

[matty573]

I put my Therma rest inside my army bivi and get inside and sleep on top of that. That way you wont slide off it in the night and it will also stay dry. You definitley need some sort of sleeping mat to insulate you from the ground. A ground 'sheet' would be pointless as this will not offer you any insulation and the bivi stops any moisture from the ground getting to you anyway.
The british army bivi is not the lightest but it is very good at what it is designed for and is very robust. Definitley worth carrying!
In my opinion.

[Jaan]

I should have specified a bit that I will be using the mat regardless of using the groundsheet or not. I will do as said - put the mat inside the bivy.

I was just worried about the underside of the bivy and the hydrostatic head. Then again it should be possible to wake up in a puddle and still be dry, from posts I've read. A groundsheet would not help in that case anyway.

[Scots_Charles_River]

Only use a grndsheet to protect the bag. If midges are out, i use my ex army bivvy and my dd travel hammock. The hammock has a midge net.

You can take a cheap karimat for the ground, then bivvy on top.

[ged]

I carry a groundsheet in case the ground is muddy, but I don't always use it. More often than not I do use it, but it's just more stuff to carry, set up, clean and pack away. I like having a sheet of some sort to spread stuff out on if I'm cooking, sorting out my kit, or lounging about, but it's often just a sheet of polythene that wrapped a pallet that was delivered at work.

[Badger74]

I carry either an IPK sheet or a plastic orange survival bag to put under mine.

[bilmo-p5]

I carry either an IPK sheet or one of the poundshop 2mx1m polytarps and a ¾-length inflatable mat in addition to the army bivibag. I move about a lot when I'm asleep and find that it is easier (for me) to roll back onto the mat than it is to sort out the mat/sleeping bag arrangement inside the bivi - it always seems to end up a higgledy-piggledy mess if I put the mat inside the bivibag.

[woof]

When using my hooped bivvi, i put a cheap foam mat underneath, to protect the mat, & then my thermarest inside. The pound shop have some cheap lightweight tarps in which should be good for this, they also have some space blankets(which i got)that should do the same job.

Rob

[sasquatch]

IPK for me as well...

[John Fenna]

I use some sort of ground sheet with the bivvy just to keep it clean and protect everything from ground debris and give me a clean dry surface to store other kit, kneel on to get into bed etc.
IPK, home made mini tarp, survival bag bin liners etc all do a fair job.
As I rarely walk far with my kit these days weight is not a major issue ....

[The Lord Poncho]

Generally I'm not a fan of groundsheets at all- when I used them I always seemed to get wetter than without from the channeling of rain water and the puddeling. A roll mat or thermarest straight on the ground, and the bivibag on top has always worked well for me.

I also have a hooped bivi bag, with a non breathable floor. The first time i used it with the roll mat on the outside i got horrendous condensation on the base. So in that instance i was forced to move the roll mat inside. Never ever had a condensation problem with the issue bag though.

If you opt to put a mat/thermarest on the inside, be careful that the mat isn't wide enough to tighten the fabric of the bivibag across the top- thus compressing the loft (and effectiveness) of your sleeping bag.

[Bushwhacker]

I use some sort of ground sheet with the bivvy just to keep it clean and protect everything from ground debris and give me a clean dry surface to store other kit, kneel on to get into bed etc

Ditto to that.

[R3XXY]

I use some sort of ground sheet with the bivvy just to keep it clean and protect everything from ground debris and give me a clean dry surface to store other kit, kneel on to get into bed etc.
.

Me too, no point in wrecking your bivi bag and getting soil in your sleeping bag.

[greenwood]

Me too, no point in wrecking your bivi bag and getting soil in your sleeping bag.

me three, always better to get a hole in a cheap ground sheet or roll mat than your more expensive bivi bag, pound land had some in last week and 2 pack space blankets

[Greek1983]

I always carry a second Army pocho just in case the area is terribly muddy.

[copper_head]

I dont carry a groundsheet in addition to my bivvi bag, trying to get my kit as light as possible at the minute and its a luxury I dont need. However if I wasn't hiking it seems like a logical idea,

[11binf]

hi ...most of the time just use a roll mat and space blanket as a ground sheet...vince g. 11b Inf...

[Native Nathan]

I converted to a Hammocker

But when I was a ground dweller I always but my rollmat under my Bivvy bag
I didn't want my bivvy bag ripped.

Rollmat £10- £20
Bivvy Bag £45 - £60

A no brainer really

[Jaan]

I converted to a Hammocker

But when I was a ground dweller I always but my rollmat under my Bivvy bag
I didn't want my bivvy bag ripped.

Rollmat £10- £20
Bivvy Bag £45 - £60

A no brainer really

I was thinking hammocks at first too, but it's much-much colder here than it is in the UK. I need to be warm and I don't want to carry over 17-18kg of stuff around. I calculated that a hammock + tarp with all it's stuff is heavier than a 1-man tent, while an army bivi with tarp is about the same, but simpler and less stuff to go wrong.

For me carrying a rollmat is not a no brainer, since I hate how big the things are. I will probably opt for a space blanket or some other small groundhseet. I want everything on the inside of my pack as I walk.

[The Lord Poncho]

For me carrying a rollmat is not a no brainer, since I hate how big the things are. I will probably opt for a space blanket or some other small groundhseet. I want everything on the inside of my pack as I walk.

A space blanket or ground sheet will not insulate you from the ground in the cold though. A roll mat will, and if it is on the outside of your pack and gets wet, you can still stick it outside of your bivi bag to keep your sleeping bag dry. They don't tend to absorb much water.

If you want something that fits inside your pack, a thermarest or similar tends to be a little more compact.

[Jaan]

A space blanket or ground sheet will not insulate you from the ground in the cold though. A roll mat will, and if it is on the outside of your pack and gets wet, you can still stick it outside of your bivi bag to keep your sleeping bag dry. They don't tend to absorb much water.

If you want something that fits inside your pack, a thermarest or similar tends to be a little more compact.

Yes I'm well aware of that and will be bringing a thermarest regardless. I also said this above. I'll be putting the thermarest inside the bivi as to not roll off of it.

However, a rollmat on the outside in addition to all of this seems a bit excessive. My question was about protection, not insulation.

[southey]

just a 3\4 length foam mat, warm and snuggy with out creating a pool of water

[PREPER]

Cut down IPK and mats various depending on season and how lightweight/low volume I want to go,

PREPER........

[Itzal]

Issue Bivvy bags are actually quite good despite how old they are, they can get a bit sweaty I find but I can't really say I have ever had a problem, they are pretty durable too, I have had mine nearly 10 years and its still going strong. Def use a roll mat or a thermarest but you can comfortably sleep with nothing else. Good alternative to carrying a group shelter when on the hills if there are only two of you too.

[Scots_Charles_River]

Issue Bivvy bags are actually quite good despite how old they are, they can get a bit sweaty I find but I can't really say I have ever had a problem, they are pretty durable too, I have had mine nearly 10 years and its still going strong. Def use a roll mat or a thermarest but you can comfortably sleep with nothing else. Good alternative to carrying a group shelter when on the hills if there are only two of you too.

But if you are only two, you can;t treat he casualty below head height. With a bothy bag you have access to all the body of the casualty and you are dry too.

[Itzal]

But if you are only two, you can;t treat he casualty below head height. With a bothy bag you have access to all the body of the casualty and you are dry too.

Lets be honest, you are never that far from help in the UK and you can that before you put them in the divvy bag. I don't find bothy bags that good for keeping the heat in personally, and the chances of cold injures are higher up high. I suppose its preference and experience, I do have a bothy bag but only take it for bigger groups.

[Jaan]

Stop digging up old threads!

[Scots_Charles_River]

Lets be honest, you are never that far from help in the UK and you can that before you put them in the divvy bag. I don't find bothy bags that good for keeping the heat in personally, and the chances of cold injures are higher up high. I suppose its preference and experience, I do have a bothy bag but only take it for bigger groups.

I had a group at a climbing Quarry a few weeks ago and when the sun went behind it got very chilly, east coast HAAR. So the 6 kids jumped into an 18man bothy bag, kept them busy for 5mins while I setup the abseil.

If you put them in a bivvy bag with a - twisted ankle, sprained knee, if they have chilled a bit - you can't assess them properly hence the bothy bag as it's over the head and does restrict access.

[Itzal]

I had a group at a climbing Quarry a few weeks ago and when the sun went behind it got very chilly, east coast HAAR. So the 6 kids jumped into an 18man bothy bag, kept them busy for 5mins while I setup the abseil.

If you put them in a bivvy bag with a - twisted ankle, sprained knee, if they have chilled a bit - you can't assess them properly hence the bothy bag as it's over the head and does restrict access.

I can't disagree with you on the fact they are useful, and I do use mine for groups, but if there is just me or only 2 of us I tend to take my divvy bag, I suppose its just what I am used to, I have had to sit out the weather in mine and I prefer it.