Loop Knots
Part of Knots and Cordage
Loop knots create a fixed or adjustable eye in the rope. They are the foundation of rescue systems, anchor points, and load-bearing connections.
Why Loop Knots Matter
A loop in a rope turns a passive length of cordage into an active tool. You can lasso a branch to pull it down for shelter building. You can clip a loop to a carabiner or toggle for load hauling. You can drop a loop around a drowning person. You can create anchor points for tarp shelters, fishing lines, snares, or climbing systems.
Not all loops are equal. Some tighten under load and crush whatever they encircle (dangerous around a person’s chest). Others hold their shape no matter the force. Some are easy to untie after loading; others jam permanently. Choosing the right loop knot for the job is the difference between a reliable system and a catastrophic failure.
The Three Essential Loop Knots
1. The Bowline
The bowline creates a fixed loop that will not slip or tighten under load, yet unties easily after being loaded. It is widely considered the single most important knot in ropework.
When to use it:
- Tying a rescue loop around a person’s torso
- Creating a fixed anchor point on a tree or post
- Any situation where the loop must not constrict
Step-by-step:
Step 1. Hold the rope with the working end (free end) in your dominant hand. The standing part (the long side going to your anchor or load) runs to your other hand.
Step 2. Form a small overhand loop in the standing part about 30 cm (12 inches) from the working end. The working end should cross over the standing part. This small loop is the “rabbit hole.”
Step 3. Pass the working end up through the loop from underneath. The “rabbit comes out of the hole.”
Step 4. Route the working end behind the standing part. The “rabbit goes around the tree.”
Step 5. Pass the working end back down through the same small loop. The “rabbit goes back in the hole.”
Step 6. Hold the working end and the near side of the large loop together in one hand. Pull the standing part with the other hand to tighten. The loop should remain fixed in size.
Safety Check
After tying, verify that the working end exits inside the loop, running parallel to the near side of the loop. If it exits outside, the knot can capsize under shock loading. Tug hard on the loop before trusting it with a life.
Common mistakes:
- Forming the initial loop backward (working end goes under instead of over) produces a left-handed bowline that is less stable
- Leaving too short a tail on the working end; leave at least 15 cm (6 inches) of tail
2. The Figure-Eight Loop (Figure-Eight on a Bight)
The figure-eight loop is stronger than the bowline and almost impossible to tie incorrectly. It is the standard tie-in knot for climbing and any high-load application.
When to use it:
- Anchor points for hauling systems
- Tying into a climbing harness or improvised harness
- Any application where the knot must not come undone and strength matters more than easy untying
Step-by-step:
Step 1. Take a bight (a U-shaped fold) of rope about 45 cm (18 inches) long. You will work with this doubled section as if it were a single strand.
Step 2. Form a loop by crossing the bight over the standing parts.
Step 3. Bring the bight under and around the standing parts (completing a full wrap).
Step 4. Pass the bight through the original loop from the top, just as you would with a basic figure-eight stopper knot.
Step 5. Dress the knot by pulling the loop and standing parts in opposite directions. The knot should clearly show the figure-eight pattern with parallel strands throughout.
| Property | Bowline | Figure-Eight Loop |
|---|---|---|
| Retained rope strength | ~60-65% | ~75-80% |
| Easy to untie after loading | Yes | Difficult |
| Easy to tie one-handed | Yes | No |
| Visual inspection | Requires knowledge | Obvious if correct |
| Works with stiff rope | Yes | Yes |
| Works with slippery rope | Add a stopper knot | Reliable as-is |
Rope Strength
Every knot weakens the rope at the knot point. The figure-eight retains about 75-80% of rope strength; the bowline retains about 60-65%. For critical loads, always account for this reduction.
3. The Alpine Butterfly Loop (Midline Loop)
The alpine butterfly creates a fixed loop in the middle of a rope without needing access to either end. This makes it indispensable for multi-person rope teams and midline anchor points.
When to use it:
- Creating a clip-in point in the middle of a ridgeline
- Isolating a damaged section of rope (tie a butterfly on each side of the damage)
- Attaching a side line to a main line at any point
Step-by-step:
Step 1. Drape the rope over your open hand with the rope crossing your palm. You need about 60 cm (2 feet) of slack to work with.
Step 2. Wrap the rope around your hand three times, creating three parallel wraps.
Step 3. Take the middle wrap (the second one) and pull it over the wrap closest to your fingertips.
Step 4. Tuck the same strand under the remaining two wraps from the palm side.
Step 5. Slide the whole assembly off your hand and pull the loop and both standing ends to tighten. The knot is symmetrical and loads equally from both directions.
Key advantage: The alpine butterfly can be loaded in three directions (either standing end or the loop) without failing. The bowline and figure-eight can only be loaded in two directions.
Loop Knot Selection Guide
| Scenario | Best Knot | Why |
|---|---|---|
| Rescue loop around a person | Bowline | Won’t tighten; easy to untie |
| Tying into a harness | Figure-eight loop | Strongest; won’t work loose |
| Anchor point at rope’s end | Bowline or figure-eight | Both work; bowline unties easier |
| Midline attachment point | Alpine butterfly | Only option for midline loops |
| Adjustable loop for snares | Running bowline | Slides to tighten, holds under tension |
| Quick temporary loop | Slip knot with stopper | Fast but only for light loads |
The Running Bowline: A Sliding Loop
A running bowline converts the bowline into a sliding noose that tightens under pull but releases easily. Tie a standard bowline, but instead of making the large loop the working loop, pass the standing part of the rope through the bowline loop. The result is a lasso-style noose that grips whatever it encircles.
Use it for:
- Retrieving objects from a distance
- Snares (for medium game)
- Cinching around bundles for hauling
Never Around People
Never use a running bowline as a rescue loop. It will constrict under load and can cause serious injury or death. Always use a standard bowline for rescue.
Practice Drills
- Speed drill: Tie 10 bowlines in a row, aiming for under 10 seconds each. Then do it behind your back.
- Blind drill: Tie each loop knot with your eyes closed. If you can’t tie it blind, you can’t tie it in the dark.
- Material variety: Practice on paracord, natural fiber cordage, shoelaces, and vines. Each material behaves differently.
- Load testing: Tie each knot, hang a heavy rock from the loop, and verify it holds. Then untie it. This builds trust in your knots.
Inspection Checklist
Before trusting any loop knot with a load:
- The knot is dressed neatly with no crossing strands
- The tail (working end) is at least 15 cm (6 inches) long
- The loop is the correct size for the intended use
- A hard tug on the loop does not cause the knot to slip or deform
- For bowlines on slippery cordage, a stopper knot (overhand) is tied in the tail
Key Takeaways
- The bowline is your default loop knot. It is fast to tie, does not constrict, and unties easily. Learn it first and learn it cold.
- Use the figure-eight loop when strength matters most. It retains more rope strength and is nearly foolproof to tie correctly.
- The alpine butterfly is the only reliable midline loop. If you need a loop in the middle of a rope, this is the answer.
- Never use a constricting loop around a person. Running bowlines, slip knots, and similar noose-style loops can kill.
- Practice until it is automatic. You will need these knots when your hands are cold, wet, shaking, or injured. Muscle memory is the only reliable path.