What is a bivvy bag?
Sometimes called Bivi bags or Bivouac sacks, these are waterproof enclosures which surround your sleeping bag, forming a cocoon of protection against the elements. Originally invented by climbers who needed emergency weather protection for their sleeping bags during multiple-day ascents of mountain peaks – the bags had to be lightweight and easily packable in a small climbing backpack.
Today’s designs have more in common with tents in terms of the materials used:
- A bottom layer typically consisting of urethane-coated nylon to make it waterproof. This is the same rugged material used for the ‘bathtub’ lower section of modern tents
- A top layer usually made of ripstop nylon (a lighter fabric) and treated with a waterproof, breathable textile. On the most expensive bivvy bags, look for Gore-Tex top layers.
Advantages of a bivvy bag
- Cheaper and more lightweight than tents
- Discreet and requires less room than a tent
- Quicker to set up and take down
- Packs down small
Disadvantages of a bivvy bag
- Less protection from the elements
- May leave condensation on your sleeping bag, meaning it will need to dry out.
How is a bivvy bag used?
- Slips over your sleeping bag – can be done before leaving to save time in the field.
- Pull it up over your head when asleep, leaving a small gap for breathing (this will also minimise condensation)
- If you have a large bivvy bag your sleep mat may fit inside it, if not it can go below the bivvy bag on the floor
- Your other kit will need a waterproof bag or cover to protect it from the elements – you could use your rucksack as a pillow.
Which bivvy bag should you buy?
Things to think about when purchasing a bivvy bag:
- Budget
- Weather
- Size
- Weight
- Breathability
Today’s designs have more in common with tents in terms of the materials used:
- A bottom layer typically consisting of urethane-coated nylon to make it waterproof. This is the same rugged material used for the ‘bathtub’ lower section of modern tents
- A top layer usually made of ripstop nylon (a lighter fabric) and treated with a waterproof, breathable textile. On the most expensive bivvy bags, look for Gore-Tex top layers.
Where to buy a bivvy bag
Most military shops will sell bivvy bags, as do outdoor/camping shops. It’s always a good idea to think what the bivvy bag will be used for first and buy accordingly.
Here are some of our favourites:
A great entry level bivi bag which is lightweight, waterproof and compact Designed with a high-quality specification and material, this bivi will keep you dry and comfortable during the night.
A waterproof membrane prevents water from leaking through the fabric while taped seams ensures this product is completely watertight. Ripstop fabric stops rips in their tracks with this heavy duty fabric
Snugpak Special Forces Bivvi Bag
Perfect for UK Weather Conditions & protecting you from evaporative and convection heat loss.
A robust and protective, breathable bivi, providing minimalist refuge from any storm. Featuring waterproof fabric and a spacious design to accommodate bulky clothing or large sleeping bags.
Jay Jay’s was founded in 1993 by our team of former Police and Military personnel. We’ve been manufacturing load-bearing equipment and supplying clothing for the military for thirty years. Our innovative, built-for-life products and industry-leading customer service have earned us an outstanding reputation that we’re incredibly proud of.
Why not try for yourself?
