How to tie up a boat in a marina, on a mooring buoy or against a harbour wall.
When you use a mooring you want to know that your boat will be safe, whether you’re simply staying for a few hours or leaving the boat over winter. In this guide, we’ll explain which ropes to use and why, and how to keep your boat safe whatever the weather.
Different Types of Rope
Rope, line or warp is made from different materials, like polyester, nylon, HMPE (Dyneema and other brands) or polypropylene. The material strands are spun to make the rope. In the marine world, 3-strand, 8-strand, 12-strand and braided ropes are most common, although there are ropes designed for pretty much every job on every type of boat.
A rope has different properties depending on the material used and how it is made. Mooring warps need the following properties:
- Stretch: absorb snatch loads from waves or wind. The rope needs to extend and recover.
- Strength: handle the strain of securing the boat year-round in a range of conditions.
- Handling: ease and comfort of handling and coiling for storage and general use. For example, braided and multi-plait ropes are more comfortable to handle than 3-strand.
Rope Materials
Nylon
Nylon has excellent elasticity – able to stretch up to 35% of the length before breaking. When wet, nylon loses up to 10% of its break load. It also shrinks and hardens when wet, making it more difficult to handle, but it is still a good choice for mooring lines.
Polyester
Excellent UV resistance and abrasions and does not shrink or lose strength when wet. Not as elastic as nylon, but good stretch recovery. Avoid pre-stretched polyester ropes, such as halyard lines. This is the best all-round rope for mooring and commonly available as 3-strand, 8-strand and braid.
Polypropylene
This is a rope with high stretch properties, but about half the breaking load of nylon and polyester. It is a floating line, and there are circumstances when polyprop can be useful, for example for waterski ropes and rescue lines, although not generally recommended for mooring. Some people like to use floating line for shorelines when rafting.
Dyneema and Similar
These modern low-stretch lines should not be used for mooring. An old halyard or spare spinnaker sheet doesn’t have the elasticity needed to absorb snatch loads and will put strain on cleats.
Tying Up
Mooring in a Marina
In a marina, there is usually limited space between berths, and it is important to keep the boat tied securely to stop it from rubbing against the pontoon or from touching another boat. A badly tied boat will surge and swing in even gentle breezes, and it is surprising how much damage can be done to glass fibre and paintwork in a short period.
See the diagram for the ideal mooring line configuration in a marina (pink ropes). This is the same for power and sailing boats.
In rough weather or if leaving the boat for the season it is a good idea to double-up all the lines. This spreads shock loads from storms, and ensures that if one rope chafes, the boat remains secured.
Fixed Lines or Not?
Some boat owners like to keep a set of made-to-measure lines attached to the pontoon. These have an eye spliced at the right length to be dropped straight over the cleat. The pontoon end can be looped with an eye splice, tied as usual or secured with a metal thimble onto a shackle.
It is easy to have permanently fitted mooring compensators or snubbers fitted to fixed lines.
The main disadvantage of fixed lines is that you’ll need a spare set of long lines onboard if you visit other harbours.
Which Ropes to Use in a Marina
The most popular mooring warps are 3-strand polyester as it is tough, long-lasting and cost-effective. As it is slightly less comfortable to handle and store, this is ideal for fixed mooring lines.
Braided polyester dock line has similar properties to 3-strand. Although it isn’t quite as hard wearing as 3-strand, it is easier to handle and coil for storage and many owners prefer it. You can buy braided lines with a pre-spliced eye loop in various lengths and diameters, or by the metre from the reel.
Mooring Alongside a Harbour Wall
Although more harbours are installing floating pontoons, there are still locations where you may need to moor alongside a fixed structure like a wall. This means considering the rise and fall of the tide. If you were to use the same configuration of ropes as in a marina, the boat would soon be dangling on the lines as the tide went out, or be pinned beneath the surface as the tide rose.
Long spring ropes and long bow and stern lines are important. No breast and quarter lines unless you’re onboard to adjust them. Always ensure that you can adjust the lines in case you get your tidal calculations wrong.
In the diagram the boat with red lines is moored alongside a wall. With a large tidal range, the bow and stern lines will be significantly longer.
Ropes for Rafting Out
Sometimes in a busy harbour you may need to tie alongside another boat instead of directly alongside the pontoon or wall. This is known as rafting, and you might see rafts six or more boats deep in some places.
Rafting etiquette and good neighbourly behaviour can make rafting a lot of fun, but the rope work looks daunting. If you are rafted, then you’re moored against a floating structure, so use the same arrangement of ropes as you would in a marina. In the diagram, the rafted boat has blue lines.
Breast and quarter lines and springs fore and aft between you and the next-door boat. In addition, you’ll need long shorelines fore and aft between you and land – this is to stabilize the raft and take some of the strain off the inside boats.
There’s lots of discussion about the length of shorelines, and there is no right answer. It is useful to have a very long rope onboard that could be used for towing, locks and shorelines. But equally, there’s no point in having a length of rope that is too heavy to handle or too large to stow easily.
Mooring Buoy or Pile Mooring
Some ‘fixed anchor’ moorings like buoys and piles have pick-up buoys with ropes already attached. Unless you are staying for a short period or are confident in the quality of these lines, then it is good practice to attach your own ropes.
The boat will move about more on a mooring, so durability and chafe resistance are important. 3-strand or 8-strand/multi-plait is preferable to braided dock line. If you use this type of mooring regularly, a line with a length of anchor chain spliced in the middle is the ideal anti-chafe solution. A less permanent solution would be to secure a length of hard-wearing hose to the line as it passes through the ring. The chain sits against the ring of the mooring buoy or pile.
Ask about our splicing services for new rope and chain.
Chafe is the Enemy
On any type of boat, chafe is the enemy of ropes. Even new warps can wear through by rubbing against each other, against the pontoon, mooring ring, fairlead or hull.
Ropes should always be rigged to avoid chafe. Reroute to avoid sharp bends around fairleads, shroud bases, deck fittings or metal toe rails.
Chafe protectors can be added to lines. These can be as simple as wrapping an old tea towel around the rope, sliding a length of hose over the rope or using a bought anti-chafe device to fix around the rope. Chafe protectors need to be durable and easy to use.
Even if you've set up your mooring lines perfectly, it is always advisable to check regularly for wear and to replace ropes that show signs of stranding, burns or damage.
Fenders
In a marina or harbour you can never have enough fenders!
They cost a few pounds, usually last years and can save you a fortune. Extra fenders will put your mind at rest in a strong wind or storm, especially if your boat is blown-on. It is best to tie fenders to a fixed part of the boat, like a toe rail, stanchion base or handrail. Fixing to guard wires risks deforming or pulling out the wires.
Standard cylinder fenders are most usual, but ball fenders are ideal for areas like the bow and stern cut away. A lightweight inflatable fender for emergencies is a good investment.
If your marina allows it, dock fenders can be attached to the pontoon with screws or bolts. These can be fitted the entire length of the berth, but are mainly used in ‘high impact’ areas like the bow or around corners of the finger pontoon.
Fender Care
As with your mooring warps, check fender lines regularly for chafe and replace when damaged. Any soft fenders can be pumped-up with a suitable adaptor - it's a good idea to keep a set onboard, as each fender manufacturer has their own style of valve.
Clean fenders with soapy water or boat cleaner, and ensure there's no grit embedded in the surface.
Fender Covers
Covers are a good way to keep old fenders looking smart, and they can stop dirty marks from transferring from the fender to the hull. But they can also trap grit in the fabric, potentially grinding this into the gelcoat. Keep fenders and fender covers clean!
Some boat owners, especially those with a wrapped hull, like to use a fender skirt or mat. This hangs between the hull and the fenders stopping any direct rubbing. A sail or cover maker can make a fender skirt to fit your boat.
Mooring Compensators
Rubber compensators or snubbers can help to reduce shock loading on cleats by absorbing some of the load. They can be very useful for marina berths affected by swell or boat wash.
Compensators are fitted by winding the mooring line around the rubber shaft and through the ends of the snubber. This makes them most suitable for fixed lines and when the boat is left for a period.
If you're ever unsure of how big or how long a mooring warp should be, or you want advice on the most suitable fenders for your boat, then pop into one of our shops - we're happy to help.