If you do add a linner.
Make sure you have four ties across the sholder area (one each side of where your neck would be) to ensure the linner does not slide down into the bag. Place ties going down the zip length at about 6 inch intervals all the way to the bottom. You need only do about two thirds of the linners length as you dont need to have a slit all the way to your feet. Make sure you have four ties at the bottom of the bag so the foot area stays still, this allows you to get in and out easily.
Tried this out in the garden under the apple tree during the weekend when it was minus 5. Snug as a bug in a an issue bivvy bag and base layers.
Sandsnakes
Make sure you have four ties across the sholder area (one each side of where your neck would be) to ensure the linner does not slide down into the bag. Place ties going down the zip length at about 6 inch intervals all the way to the bottom. You need only do about two thirds of the linners length as you dont need to have a slit all the way to your feet. Make sure you have four ties at the bottom of the bag so the foot area stays still, this allows you to get in and out easily.
Tried this out in the garden under the apple tree during the weekend when it was minus 5. Snug as a bug in a an issue bivvy bag and base layers.
Sandsnakes