How to sleep warm
- 1Set your ground insulation — an insulated pad (in winter, foam plus an inflatable) so no part of you sleeps directly on the ground.
- 2Change into dry clothes — swap sweaty day clothes for dry base layers and dry socks before you get cold; put a hat on.
- 3Eat a snack and drink water — fuel and hydration let your body produce heat through the night.
- 4Fill a hot water bottle (if cold) — a leakproof bottle at the feet or core; tuck tomorrow's clothes around it to pre-warm them.
- 5Get in warm — do a few jumping jacks first if you're already cold, so you enter the bag warm rather than trying to warm a cold bag.
- 6Keep your face out and vent — sleep with mouth and nose outside the bag and a tent vent cracked so moisture leaves.
- 7Prep for morning — boots inside or under the bag (bagged if wet) so they don't freeze; next-day layers pre-warmed at the foot of the bag.
When to use it
- Every cold-season or high-elevation campout, where a bad night can become a real cold-injury risk.
- Shoulder-season trips where nights drop much colder than the day suggested.
- Teaching newer scouts why they were cold last time — usually the ground, damp clothes, or going to bed chilled, not "a bad bag."
Common mistakes & safety
- Being cold at night is a hypothermia pathway. Persistent overnight cold, especially when damp, can progress — warm up, add insulation, and get help if someone shows confusion or shivering that won't stop.
- Ground insulation is a safety item, not comfort. Without an insulated pad, even a good bag sleeps cold because the ground pulls heat out of you.
- Keep insulation dry. Damp insulation loses much of its warmth — dry clothes, face-out sleeping, and venting keep it dry.
- No open flame or unvented heaters in a tent. Never use stoves, catalytic heaters, or charcoal to warm a closed tent — fire and carbon-monoxide risk. Warm with insulation, clothing, and a hot water bottle.
- Don't over-bundle to the point of sweating — sweat dampens insulation and makes you colder later; aim for warm-but-dry.
- Watch the whole patrol. The youngest and smallest, and anyone who got wet during the day, chill fastest — check on them before lights out.
Going deeper
- "Warm the bag, don't let the bag warm you." A sleeping bag only traps the heat you bring into it — go in already warm (snack, movement, dry clothes) instead of waiting to warm a cold bag.
- The three-question cold check. Off the ground? Dry? Went to bed warm? Almost every cold night fails one of these.
- Pre-warming trick. The same hot water bottle that warms your feet can be tucked into your stuff sack of tomorrow's clothes so you dress into warm layers in the morning.
Official source
Eight essentials for staying warm cold-weather camping — Scouting Magazine →Never heat a closed tent with any flame or fuel-burning device — carbon monoxide is deadly.