Emergency Shelters: Survival Bags, Tarps, Bothy Bags & Bivi Bags
Why Carry an Emergency Shelter?
Weather conditions can change quickly outdoors, particularly in exposed or mountainous areas. If you become injured, lost, delayed or simply need to stop for an extended period, protection from wind and rain can make a significant difference to your comfort and safety.
Emergency shelters range from very simple survival bags weighing relatively little to reusable group shelters and bivi bags designed for spending a night outside.
The right option depends on where you're going, the number of people in your group, how much weight and bulk you're prepared to carry, and whether the shelter is intended purely for emergencies or for planned overnight use.
Survival Bags
The traditional plastic survival bag is one of the simplest emergency shelters you can carry.
Essentially a large, tough waterproof bag, it provides a barrier against wind and rain and can help reduce heat loss while you are waiting for assistance or unable to continue your journey.
Their simplicity has several advantages. Survival bags are generally inexpensive, compact and easy to carry, making them particularly useful as a basic emergency item in a walking or hiking pack.
They're intended primarily as emergency protection rather than comfortable overnight accommodation.
A survival bag can be particularly useful when:
- someone in your group becomes injured or unwell
- you have to stop unexpectedly in poor weather
- you're waiting for assistance
- you need additional protection from wind and rain
After use, inspect reusable survival bags carefully for tears or damage before relying on them again.
Tarp Shelters
Tarps are among the simplest and most versatile lightweight shelters.
Usually manufactured from waterproof fabric, outdoor tarps typically incorporate reinforced attachment points that allow them to be configured in different ways using cord, poles, walking poles, trees or other suitable anchor points.
This flexibility allows a tarp to provide anything from a simple overhead rain shelter to a more enclosed sleeping arrangement.
In suitable weather, experienced users may use a tarp as their primary lightweight shelter. In colder or wetter conditions, additional protection such as a suitable bivi bag may be required to protect both the sleeper and sleeping bag.
Tarps are particularly useful when you want:
- a lightweight and adaptable shelter
- protection for cooking or rest stops
- additional covered space around camp
- a minimalist shelter for planned overnight trips
The effectiveness of a tarp depends heavily on how and where it is pitched, so it's worth practising different configurations before depending on one outdoors.
Bothy Bags
A bothy bag is a lightweight, reusable group shelter designed to provide rapid protection from poor weather.
Rather than being pitched like a tent, the group gets inside and normally sits around the edges. The occupants help give the shelter its shape while their combined body heat can create a noticeably warmer and more sheltered environment inside.
Although originally developed as emergency shelters, bothy bags are also extremely useful for planned stops in difficult weather.
They can provide shelter for:
- emergency situations
- rest and meal breaks
- route planning and map reading
- waiting for slower members of a group
- dealing with minor injuries
- group stops in exposed conditions
Different capacities are available, making them particularly useful for walking groups, outdoor organisations and other group activities.
A bothy bag is not the same as a bothy building. In this context, it means the portable fabric group shelter carried in a rucksack.
Bivi Bags
A bivi — or bivvy — bag provides a waterproof or weather-resistant protective cover around a sleeping bag and occupant.
At its simplest, a bivi bag resembles an outer cover for a sleeping bag. More elaborate versions may incorporate hoops or other structures to provide additional space around the head and upper body.
They occupy the ground between basic emergency protection and a conventional tent.
Compared with a tent, a bivi bag can offer advantages in:
- packed size
- weight
- speed of deployment
- use where space is limited
The trade-off is considerably less living space and, depending on the design and conditions, potentially less protection and comfort than a suitable tent.
When choosing a bivi bag, consider waterproofing, breathability, ventilation, packed weight and the amount of internal space you require.
Which Emergency Shelter Should I Choose?
There isn't a single shelter that is best for every situation.
For basic emergency backup:
A survival bag provides simple protection with relatively little cost or complexity.
For a walking group:
A bothy bag provides rapid shelter for several people and can also be useful during planned breaks in poor weather.
For versatile lightweight shelter:
A tarp provides considerably more pitching options but requires more knowledge and preparation to use effectively.
For sleeping outside:
A bivi bag provides a more appropriate individual sleeping shelter and can form part of a lightweight overnight system.
Some people carry more than one option. A lightweight survival bag, for example, may remain in a rucksack as emergency equipment even when a tent, tarp or bivi is being carried for planned accommodation.
Emergency Shelters Are Only Part of Your Safety Equipment
Carrying a shelter shouldn't replace appropriate preparation, clothing, navigation equipment or an understanding of the conditions you are likely to encounter.
For trips into more remote or exposed environments, consider what would happen if you were forced to remain stationary for several hours.
Your clothing, insulation, emergency shelter, food, water, communications and other safety equipment should work together to help you cope with an unexpected delay.
Most importantly, learn how to use your equipment before you need it in an emergency.