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Established Since 1986

Yachtfend Tips

10 Yacht Mooring
Mistakes That Cost
Real Money

And how to fix every one of them

After nearly 40 years in the mooring products business, we’ve seen every mistake in the book. Some of them we’ve made ourselves. None of them are complicated to fix — and every single one costs far less to prevent than to repair.

Here are the ten most common.

40 yrs
In the mooring products business. We’ve seen these mistakes more times than we can count.
€100+
Per gelcoat repair spot. A full respray runs €300–500 per metre.
10
Fixable mistakes that account for the vast majority of avoidable dock damage.

The 10 Mistakes

1

Undersized Fenders

This is number one for a reason. We see it constantly: a 60-foot motor yacht with fenders that belong on a 30-footer. The fender compresses to nothing on contact, and the hull hits the dock anyway. The fenders are present but doing nothing useful.

The Fix

One inch of fender diameter per 4–5 feet of yacht length. When in doubt, go one size bigger — a larger fender never caused a hull repair. Fender Size Guide →

2

Not Enough Fenders

Three fenders might be fine for a small sailing yacht in a calm marina. It is not enough for a 50-footer in an exposed berth, or for any yacht doing a Med stern-to alongside close neighbours. Gaps in coverage mean gaps in protection.

The Fix

One fender per 10 feet of waterline, minimum. For Med stern-to berthing, carry at least six regardless of yacht size. Always keep one or two spares aboard.

3

Fenders Set Too High

If the bottom of your fender is two feet above the waterline, the bottom two feet of your hull are completely unprotected. That’s exactly where the dock edge tends to sit — and where the contact happens. This mistake is easy to miss because the fenders look deployed and everything seems fine.

The Fix

Hang fenders so the bottom is just above the water surface. Check height after tidal changes on floating docks, and whenever you move to a new berth with different freeboard neighbours.

4

No Fender Covers

Bare PVC fenders leave scuff marks on gelcoat. It might not show the first time, but after a month in a marina berth with regular wake wash, you’ll see black marks running along the waterline. Over time, that marking becomes permanent discolouration and surface damage.

The Fix

Neoprene fender covers on every fender. Non-marking, UV resistant, easy to clean, and they extend the life of the fender itself. Shop Fender Covers →

Mistakes 1–4 are all about fender selection and setup — the foundation. Get these right and you’ve eliminated the most common causes of dock-related hull damage before the lines are even tied.

5

Using the Wrong Line Material

Nylon stretches 15–25% under working load. If you’re using nylon breast lines in a marina berth, your yacht is bouncing around more than it should be, putting repeated dynamic loads on cleats and dock hardware. Nylon also degrades significantly faster in UV exposure — relevant when lines stay deployed for weeks at a time.

The Fix

Use polyester for all marina mooring lines — low stretch, UV resistant, maintains strength when wet. Save nylon for anchor rodes and mooring balls where shock absorption is the point. Shop Mooring Lines →

6

Lines Too Tight

Mooring lines that are bar-tight put enormous static load on cleats, chocks, and dock hardware. When a wake or gust adds dynamic load on top of that, something gives — either the cleat pulls out, the chock bends, or the line itself parts. We’ve seen all three.

The Fix

Leave enough slack for the yacht to move naturally without slamming. Floating docks need less slack. Fixed docks with significant tidal range need more — check that lines won’t go bar-tight at low water.

7

Lines Too Loose

The opposite problem. Excessively slack lines let the yacht drift far enough that fenders lose contact with the dock entirely, and the hull hits unprotected. You can have perfectly sized fenders in perfect position and still sustain hull damage if the lines are slack enough to let the boat drift past them.

The Fix

Find the middle ground. The yacht should move gently with swell and wake, but fenders should stay engaged with the dock surface at all times. Check tension after any significant wind shift or change in conditions.

8

No Chafe Protection on Lines

A mooring line passing over an unprotected fairlead or chock will eventually chafe through. We’ve seen 20mm lines worn to half their diameter in a single season because nobody fitted a rope cover at the chafe point. The line looks fine at the cleat — the damage is hidden inside the fairlead where you can’t see it.

The Fix

Neoprene rope covers on every line where it contacts metal or fibreglass — fairleads, chocks, rail edges. Protects both the line and the gelcoat beneath it. Shop Rope Covers →

9

Leaving Fenders Deployed While Underway

We know — you’re just going to the fuel dock and back. But UV exposure degrades fenders faster than anything else, trailing fenders create drag and can snag on buoys or debris, and it simply doesn’t look good. It’s also a signal to other mariners that you’re not paying full attention.

The Fix

Stow fenders every time you leave the berth, no exceptions. With fender hooks it takes 30 seconds to pull them all in. Deploy again on approach — it’s a habit that costs nothing and protects both your fenders and your reputation on the water.

10

No Spring Lines

Bow and stern lines hold the yacht in place laterally. But without spring lines, the yacht surges forward and back with every wave, wake, and gust. This puts repeated shock loads on all your lines and fenders, accelerates chafe at every contact point, and — if the surge is large enough — lets the hull slam against the dock.

The Fix

Always rig at least one forward spring and one aft spring line whenever leaving your yacht in a berth. In any kind of swell or tidal harbour, springs are not optional — they’re what keeps everything else working correctly.

The Cheap Insurance Principle

Every item on this list is a low-cost fix. Bigger fenders, neoprene covers, polyester lines, rope covers — none of these are expensive relative to the hull repairs, gelcoat resprays, or structural damage they prevent.

One good set of properly sized fenders with covers costs less than a single professional gelcoat repair. Rope covers cost less than a chafe-damaged mooring line. The maths is straightforward — the only question is whether you act before or after the damage happens.

After 40 years of watching yachts come and go in marinas across Europe, we’ve never once seen an owner regret spending money on proper mooring gear. We’ve seen plenty regret not doing so.

Fix Every Mistake on This List

Fenders, covers, polyester mooring lines, rope covers, and fender hooks — everything you need, from Yachtfend.

Frequently Asked Questions

Which of these mistakes causes the most expensive damage?
Undersized fenders and missing chafe protection are responsible for the most costly repairs we see. Undersized fenders lead to direct hull-to-dock contact — gelcoat damage, fibreglass damage, and in bad cases structural damage to stanchion bases and rails. Chafe-damaged lines fail without warning, which can mean the yacht breaking free entirely.
How do I know if my current fenders are the right size?
The guideline is one inch of fender diameter per 4–5 feet of yacht length. So a 45-foot yacht needs fenders with at least a 9–11 inch diameter. If your fenders compress significantly when the yacht presses against the dock, they’re too small. If you can push your thumb into the fender and feel it bottom out easily, the same applies.
Is it worth replacing lines that look fine but are several years old?
Inspect rather than assume. Look for stiffness, discolouration, chafe spots, and any sign of the outer braid wearing through. Polyester mooring lines in normal marina use last 3–5 years. If lines are approaching that age and showing any of those signs, replace them — a line failure at 2am in a rising wind is not the time to discover they were overdue.
Do these mistakes apply equally to sailing yachts and motor yachts?
Yes, though motor yachts are typically heavier at the same length, which makes undersized fenders and incorrect line tension more consequential. Sailing yachts with limited deck hardware sometimes have fewer cleat options, making spring line rigging trickier — but no less important. The principles are the same across all vessel types.