Bivy bags

Plan a suitable sleeping bag and insulated mat as well. A thin bivy cover blocks wind and, depending on its construction, rain, but does not provide the filling and ground insulation of a complete sleeping system.

Moisture also comes from your body and breath. Ventilate around the head, breathe outside and dry the cover after use. Even a breathable upper can collect condensation when conditions prevent moisture from escaping quickly enough.

Check the rules for your intended overnight location before the trip. Protected areas and planned overnight stays may have different requirements from a real emergency. Also choose a spot away from rockfall, water channels and other apparent hazards.

Mesh protects against insects. For rain you need a suitable closed cover or additional weather protection. With a modular shelter, check which parts are supplied and which you need to pack separately before leaving home.