Boat Fender Buying Guide: Types, Sizes and How Many You Need
Good boat fenders are cheap insurance for your hull. This guide covers the main types of fenders, how to choose the right size, how many to carry and how to hang them — wherever you boat, from Australia and Asia to the USA and Europe.
What do boat fenders do?
A boat fender (called a boat bumper in parts of the USA) sits between your hull and a jetty, pontoon, sea wall or another boat. It absorbs the knocks that happen when you come alongside, when wind and wash move the boat at its berth, and when boats raft up together. Without fenders, those knocks go straight into your gelcoat or paintwork.
The main types of boat fenders
- Cylindrical inflatable fenders — the most common type. Hung vertically along the side of the boat. They are effective but bulky to store and need to be kept at the right pressure.
- Round (ball) fenders — large spherical fenders, often used at the bow or stern and on larger vessels.
- Flat and foam fenders — flatter fenders that do not roll, popular against pilings and fixed walls.
- Transom and corner fenders — shaped to protect corners and the stern.
- Telescopic air-free fenders — like the POP Fender. They work like a cylindrical fender when in use, then compress to a fraction of their length for storage. With no air inside, they cannot burst or deflate.
What size boat fender do I need?
Fender size depends mostly on the length and weight of your boat and on where you moor. A common rule of thumb is to allow roughly 1 inch (2.5cm) of fender diameter for every 4–5 feet (1.2–1.5m) of boat length, and to go larger for heavier boats or exposed berths. Longer fenders give more protection as the boat moves up and down against a fixed jetty.
The POP Fender is 620mm (24.4in) long in use, with 165mm (6.5in) and 215mm (8.5in) diameter options. If you are unsure which suits your boat, call us and we will help you choose.
How many fenders do I need?
A good starting point is at least three fenders on the side you are mooring against — one near the widest point of the hull and one towards each end. Many boaters carry a full set for both sides so they never have to move fenders across when the berth changes. Carry extra if you raft up with other boats or moor in rough or tidal water.
How to hang boat fenders
- Tie fenders to a cleat, rail or stanchion base with a secure hitch, so they cannot slip.
- Set the height so the fender protects the part of the hull that will touch the jetty or pontoon. For a low floating pontoon that is usually just above the waterline; for a high fixed jetty, hang them higher.
- Put fenders out before you come alongside, and bring them in once you are under way — trailing fenders are a common sight, and an easy one to avoid.
- Check them as the tide and wind change, especially overnight.
Storing and caring for fenders
Storage is the biggest problem with traditional fenders: a set of inflatable fenders can fill a whole locker. Telescopic fenders solve this — a POP Fender stows at 250mm (9.8in), less than half its working length. Rinse fenders with fresh water after use in salt water and keep them clean so grit does not scratch the hull.
Why boaters choose POP Fender
The POP Fender is a quality boat fender designed in Europe and made in Germany and Austria. It is air-free, non-squeaking, UV and weather resistant, works below the waterline and pops down for storage. We ship free across Australia and with FedEx to Asia Pacific, the USA and Europe.