What size tarp should I carry?

For one person, roughly 8x10 feet is the sweet spot; for two people with gear, 10x12 feet. Bigger tarps weigh more and take longer to pitch in wind — pick the size for the shelter you will actually build.

How do I pitch a tarp with no trees?

Use trekking poles or cut poles with a knife, and stake them out with guy lines. In open ground, tie off to a pack, a bike or heavy rocks and use low angles for wind resistance.

Do I need a bivvy as well as a tarp?

A bivvy adds wind protection and keeps splash off, and can be used alone in emergencies. A tarp alone is lighter and more flexible — most people carry a tarp first, then add a bivvy for cold, windy seasons.

How do I stop condensation under a tarp?

Leave one side open for airflow, keep fabric off your bag, and avoid cooking under the tarp in cold weather. Ventilation solves most condensation, and it matters more than the fabric you choose.

Field Article // Shelter Building

Emergency Shelter: The 20-Minute Tarp System

A tarp is the fastest route to real shelter. Pick the site first, then the shape — the difference between a dry night and a wet one is usually the ground, not the knot.

Survival Video Hacks Field DeskSep 30, 2026 6 min read

Key takeaways // 30-second read

Choose the site before the shape: high ground, no overhead hazards, a natural windbreak, and insulation underneath you.
A taut A-frame with one end closed beats a loose, elaborate pitch — taut fabric does not flap or leak.
Two knots cover almost every tarp job: the bowline for corner loops and the taut-line hitch for adjustable lines.
Build an insulating layer under you — leaf litter, boughs or a pad — because ground contact drains body heat far faster than air.
Keep ventilation at the high end of the shelter or condensation will wet your sleeping bag from the inside.

Site selection beats shelter design

Ten minutes spent choosing ground is worth more than an hour spent tying knots. Look for:

High ground with a slight slope, never the bottom of a gully where water collects.
No dead or leaning trees overhead. Widow-makers kill campers more often than exposure.
Natural windbreak — the lee side of a rock, bank or dense trees, not the ridge line.
Dry, insulating ground. A thick layer of leaf litter, pine boughs or a foam pad underneath matters as much as the roof above you.

The 20-minute A-frame

Ridge line. Run a line between two trees at roughly waist height, or use a trekking pole and stakes when there are no trees.
Secure the centre. Drape the tarp over the line so equal fabric hangs on both sides. Fix the ridgeline grommets with a bowline or a simple overhand on a bight.
Stake the corners. Pull the four corners out and down at 45 degrees. Taut fabric does not flap and does not leak.
Close one end. Fold one end inward and weight it with a pack or a rock. This is the difference between a roof and a shelter.
Raise the other end. Prop the open end up with a pole for ventilation — condensation soaks a sleeping bag overnight.

Two knots that cover almost everything

The bowline makes a loop that never jams and takes load without slipping: perfect for tarp corners. The taut-line hitch lets you tighten a line that has stretched. Add a few figure-eight-on-a-bight loops pre-tied in your guy lines, and pitching gets much faster in cold hands and in the dark.

Shapes for conditions

Plow point: one lifted corner, three staked — the fastest shelter and excellent in wind.
A-frame: best all-round rain protection.
Lean-to: a reflector for a fire on a clear cold night, but poor rain cover.
Diamond fly: broad coverage for two people with gear, and sheds heavy rain well.

Insulation and ventilation

Never lie directly on the ground: it conducts heat away roughly twenty times faster than air. Build a bed of dry boughs, leaves or cardboard, then a foam pad on top. Keep the tarp off your face — fabric that touches a sleeping bag collects condensation and wets the bag from the inside. Leave ventilation at the high end, and tighten the low end against the wind.

Gear & Equipment // Tested