Emergency Shelters: Survival Bags, Tarps, Bothy Bags & Bivi Bags

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, having protection from wind and rain can make a significant difference to your comfort and safety.

Emergency shelters range from simple survival bags to reusable group shelters, lightweight tarps and bivi bags designed for sleeping outdoors.

The right option depends on where you're going, how many people you're travelling with, the weight and bulk you're prepared to carry, and whether the shelter is intended for emergencies or planned overnight use.

This guide explains the main types of emergency shelter, their advantages and limitations, and what to consider before choosing one.

Why Carry an Emergency Shelter?

An unexpected stop in poor weather can quickly become uncomfortable, particularly when you're no longer moving and generating as much body heat.

Wind and rain can increase heat loss, while wet clothing and prolonged exposure may increase the risk of hypothermia.

An emergency shelter helps reduce exposure to the elements and provides a more protected place to rest, assess a situation or wait for assistance.

It can be particularly useful for:

• Hillwalking and mountain hiking.
• Remote backpacking trips.
• Outdoor group activities.
• Unexpected delays or injuries.
• Rest stops during severe weather.
• Emergency overnight situations.

However, a shelter is only one part of an effective emergency kit. It does not replace suitable clothing, insulation, navigation equipment or emergency planning.

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.

Survival bags are generally inexpensive, compact and straightforward to use, making them useful additions to walking and hiking packs.

Advantages of Survival Bags

• Simple to carry and deploy.
• Provide basic wind and rain protection.
• Generally inexpensive.
• Useful when an injured or exhausted person needs to remain stationary.
• Can form part of a wider emergency survival kit.

Limitations of Survival Bags

Most basic plastic survival bags are not breathable, so condensation can accumulate inside them.

They also provide little insulation by themselves. Although they reduce exposure to wind and rain, you still need appropriate insulating clothing and protection from the cold ground.

A survival bag should generally be regarded as emergency protection rather than comfortable overnight accommodation.

Keep breathing openings clear and follow the manufacturer's instructions. Never seal yourself completely inside an airtight bag.

After use, inspect reusable survival bags for tears or punctures 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 have reinforced attachment points that allow them to be pitched in different configurations 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.

Advantages of Tarp Shelters

• Lightweight and adaptable.
• Can provide generous covered space relative to packed size.
• Useful for rest stops and campsite shelter.
• Suitable for a variety of pitching configurations.
• Can form part of a minimalist overnight sleeping system.

Limitations of Tarp Shelters

Unlike a fully enclosed tent, a tarp may leave some sides exposed to wind-driven rain, insects and changing weather conditions.

Its effectiveness depends heavily on how and where it is pitched.

Tarps also require suitable attachment points or supporting equipment, which may not always be available in an emergency.

In colder or wetter conditions, additional protection such as a suitable bivi bag may be needed to keep your sleeping equipment dry.

Practise different pitching configurations before depending on a tarp in remote locations.

Are Tarps Suitable for Emergency Use?

A tarp can provide useful emergency protection, particularly when you have time and suitable conditions to pitch it correctly.

However, it generally requires more preparation than a survival bag or bothy bag.

For this reason, tarps are often better suited to planned lightweight camping, bushcraft and general outdoor shelter than situations requiring immediate protection.

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 conventional 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.

Bothy bags are particularly popular with hillwalking groups and outdoor organisations because they can be deployed relatively quickly during unexpected stops.

When Are Bothy Bags Useful?

• Emergency situations involving walking groups.
• Rest and meal breaks during poor weather.
• Route planning and map reading.
• Waiting for slower members of a group.
• Providing shelter while dealing with minor injuries.
• Group stops in exposed conditions.

Choosing the Right Bothy Bag Size

Bothy bags are available in different capacities, usually described by the number of people they are intended to accommodate.

Choose a size appropriate for your group, taking into account the manufacturer's stated capacity and the amount of space available for equipment.

A shelter designed for several people may be less practical for someone travelling alone because the occupants help support its shape.

Ventilation and Safety

Although bothy bags provide useful protection from wind and rain, moisture and condensation can accumulate inside them.

Use any ventilation features provided and follow the manufacturer's instructions.

Never operate a camping stove or other fuel-burning appliance inside a bothy bag. These appliances present serious fire and carbon monoxide risks.

A bothy bag is not the same as a bothy building. In this context, it refers to the portable fabric group shelter carried in a rucksack.

Bivi Bags

A bivi bag, also commonly called a bivvy bag, provides a protective outer cover around a sleeping bag and its occupant.

At its simplest, a bivi bag resembles a weather-resistant cover for a sleeping bag. More elaborate designs may incorporate hoops or other structures to provide additional space around the head and upper body.

Bivi bags occupy the ground between basic emergency protection and conventional tents.

Advantages of Bivi Bags

• Compact packed size.
• Relatively low weight.
• Quick deployment.
• Useful where pitching space is limited.
• Suitable for certain lightweight overnight trips.

Limitations of Bivi Bags

The main disadvantage is the lack of living space compared with a tent.

There may be little room for changing clothes, organising equipment or sitting upright.

Condensation can also be an issue, particularly in cold and humid conditions.

Some bivi bags are designed primarily for emergency use, while others are intended for repeated overnight camping.

It is important to choose a design appropriate for your intended activity.

Breathable Versus Non-Breathable Bivi Bags

Not all bivi bags are constructed in the same way.

Breathable bivi bags use fabrics designed to allow some water vapour to escape while resisting rainwater penetration. Their performance depends on the material, weather conditions and ventilation.

Non-breathable emergency bivi bags provide a simple protective barrier but can trap considerable condensation.

For planned overnight use, breathability, ventilation and internal space are particularly important considerations.

Always keep breathing openings unobstructed and follow the manufacturer's instructions.

Do You Need a Sleeping Bag Inside a Bivi Bag?

For most planned overnight use, a bivi bag forms part of a sleeping system rather than replacing a sleeping bag.

The bivi provides weather protection, while the sleeping bag and insulated sleeping mat provide warmth.

Basic emergency bivi bags may be used differently, depending on their design, but should not be assumed to provide sufficient insulation on their own.

Which Emergency Shelter Should You 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.

It is particularly useful as a backup item carried in a walking or hiking rucksack.

For Walking Groups

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 a wide range of pitching options and can form part of a lightweight camping system, although it requires more preparation and skill.

For Sleeping Outdoors

A bivi bag provides individual weather protection and can form part of a compact overnight sleeping system.

For repeated overnight use, choose a model designed for that purpose rather than relying on a basic emergency survival bag.

Can You Carry More Than One Type of Shelter?

Yes. Different shelters can serve different purposes.

For example, a backpacker may carry a tent or tarp for planned overnight accommodation while keeping a lightweight survival bag in their emergency kit.

A walking group might carry a bothy bag for unexpected stops even when nobody intends to camp overnight.

The important consideration is whether the equipment provides a useful additional capability without creating unnecessary weight and bulk.

Emergency Shelters and Hypothermia

One of the main reasons for carrying emergency shelter equipment is to reduce exposure to cold, wet and windy conditions.

Hypothermia occurs when the body loses heat faster than it can produce it, causing core body temperature to fall dangerously low.

It can develop in relatively mild conditions, particularly when someone is wet, exhausted, injured or unable to keep moving.

An emergency shelter can help by reducing wind exposure and protecting occupants from rain, but it does not generate heat or necessarily provide meaningful insulation.

Suitable insulating clothing, a sleeping bag or other insulation, and protection from cold ground remain important.

If someone shows signs of hypothermia, seek appropriate emergency assistance. In the UK, call 999 or 112 when urgent help is needed. In mountainous areas, ask for Police and then Mountain Rescue.

How to Use Emergency Shelters Safely

Before relying on any emergency shelter, make sure you understand how it works and what its limitations are.

• Practise deployment: Familiarise yourself with the shelter before taking it into remote areas.
• Choose a safe location: Avoid unstable ground, flood-prone areas and exposure to falling rocks or branches.
• Maintain ventilation: Keep breathing openings clear and use ventilation features as instructed.
• Keep away from flames: Never operate stoves, heaters or other fuel-burning appliances inside enclosed emergency shelters.
• Protect against ground heat loss: Use suitable insulation beneath you where possible.
• Check your equipment: Inspect shelters for tears, damaged seams or missing components before trips.
• Dry before storage: Clean and dry reusable shelters thoroughly after use.

Emergency Shelters Are Only Part of Your Safety Equipment

Carrying an emergency shelter should not replace appropriate preparation, clothing, navigation equipment or an understanding of the conditions you are likely to encounter.

For trips into remote or exposed environments, consider what would happen if you were forced to remain stationary for several hours.

Your clothing, insulation, 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.

Final Advice on Choosing an Emergency Shelter

Survival bags, tarps, bothy bags and bivi bags all provide useful forms of outdoor protection, but each is designed for different circumstances.

For a simple emergency backup, a survival bag may be sufficient. For walking groups, a bothy bag offers rapid communal shelter. Tarps provide versatility, while bivi bags are more suited to individual overnight protection.

Whichever option you choose, consider the conditions you may encounter, the equipment's limitations and how it fits into your wider outdoor safety kit.

Explore our Outdoor Survival and Emergency Equipment department for more information and suitable equipment.