How High Should a Zip Wire Start?

The short answer

Higher than you think… but not by loads.

Most people underestimate how much height you lose through sag, so they start too low and then try to fix it by over-tightening the cable.

That’s the wrong way round.

Height should be doing most of the work — not tension.

What you’re aiming for

As a rough guide, most domestic zip wires work well with a start height of around 8–12% of the total run.

So on a 30m line, you’re typically looking at somewhere between 2.4m and 3.6m at the start point.

That gives you enough drop for a smooth ride without turning it into a rocket.

Why height matters more than tension

This is where a lot of setups go wrong.

If the start point is too low, people crank the cable tighter to try and “force” the rider across.

What that actually does is:

• Put unnecessary load into your anchors
• Increase wear on your cable and components
• Make the ride feel fast and harsh

A good zip wire should work because of the height difference, not because it’s been pulled tight.

What happens if it’s too high?

Too much height isn’t ideal either.

You’ll end up with:

• Excessive speed
• A sharper drop at the start
• A less controlled ride, especially for kids

It might feel exciting the first couple of runs, but it’s not something most families enjoy long term.

What happens if it’s too low?

This is far more common.

If your start point is too low:

• Riders lose momentum halfway along
• Heavier users get close to the ground
• You’re tempted to overtighten the system

And that’s where problems start creeping in.

Getting it right in practice

The easiest way to approach it:

1. Set your end height first (making sure there’s safe ground clearance)
2. Build your start platform higher than you think you need
3. Run the cable with a natural sag
4. Test with a real rider and adjust in small steps

It’s much easier to come down slightly than it is to fix a setup that’s too low.

Don’t forget rider weight

A 30kg child and a 100kg adult behave very differently on the same line.

Heavier riders will:

• Create more sag
• Travel faster
• Sit lower in the middle

So your setup should always account for the heaviest likely user, not the lightest.

A simple check

Once it’s set up, you’re looking for:

• A smooth start — not a sudden drop
• Enough speed to reach the end comfortably
• Good ground clearance at the lowest point

If the rider struggles to reach the end → too low or too loose
If it feels overly fast → too high or too tight

How we approach it

We always design around real use in real gardens.

That means sensible start heights, controlled sag, and setups that work for both kids and adults — without needing everything cranked to the limit.

Final thought

If you get the height right, everything else becomes easier.

You won’t need to overtension the cable, the ride will feel smoother, and the whole system will last longer.

Start with height. Fine-tune with tension.