Guide
Building a finger pontoon: how wide does it need to be for your boat?
For motorboats and sailing boats up to 8 m long, we recommend a finger pontoon at least 1 m wide, which is also the manufacturer's advice. Larger boats get 1.5 m. The finger should be about two thirds to three quarters as long as your boat. A 1 × 5 m finger costs €1,272.50 net.
What is a finger pontoon?
A finger pontoon is a narrow jetty that projects at right angles from the main jetty into the water. Your boat lies alongside it, you step on and off comfortably from the side, and the boat is moored on two sides instead of just at the bow. In marinas it is also called a catway, because it separates two berths.
With our HDPE floats, a finger pontoon is simply another part of the jetty: it is pinned straight onto the main jetty with the same coupling pins and floats at the same height as the main jetty at any water level.
How long should a finger pontoon be?
About two thirds to three quarters of the boat's length. That is the usual rule of thumb in marinas: the finger reaches far enough for you to walk along it from the stern to past the middle of the boat and make fast at both bow and stern.
For a 7 m boat that is 4.7 to 5.3 m, so a 5 m finger on the 50 cm grid. Better to round up than down: a slightly longer finger gives the boat more support, while one that is too short leaves the stern swinging freely.
How wide should a finger pontoon be for your boat?
That depends mainly on the length of the finger, less on the boat itself. A long, narrow finger moves more when you walk on it or a boat pushes against it. The manufacturer therefore recommends a width of at least 1 m. Our guide values:
- 1 m (two floats wide): the minimum width for a finger pontoon and our recommendation for most motorboats and sailing boats up to 8 m. You walk on it safely even with luggage in hand, and the cross bollards have enough room.
- 1.5 m (three floats wide): for boats from about 8 m and fingers from 6 m long. The wider finger lies more calmly in the water and copes better with the greater forces of a heavy boat in wind.
We do not recommend a finger narrower than 1 m, i.e. only one float wide. These are guide values. Wind, waves and the weight of your boat all play a part. Tell us the length, beam and weight of your boat in your enquiry, and we will set the width in the quote.
Finger pontoon: guide values by boat length
| Boat length | Finger (W × L) | Floats | Load capacity | Price net |
|---|---|---|---|---|
| up to 4 m | 1 × 3 m | 12 | 1.05 t | €758.50 |
| 5 m | 1 × 3.5 m | 14 | 1.2 t | €887.00 |
| 6 m | 1 × 4.5 m | 18 | 1.6 t | €1,144.00 |
| 7 m | 1 × 5 m | 20 | 1.75 t | €1,272.50 |
| 8 m | 1 × 6 m | 24 | 2.1 t | €1,529.50 |
| 10 m | 1.5 × 7.5 m | 45 | 3.9 t | €2,800.50 |
| 12 m | 1.5 × 9 m | 54 | 4.7 t | €3,361.50 |
Guide values: finger length about two thirds to three quarters of the boat's length, on the 50 cm grid. H40 floats including coupling pins, bolt sets and spacer rings, calculated as a single finger, excluding VAT, without main jetty, tools, accessories, anchoring and freight (calculated individually). Load capacity calculated at 350 kg per m².
How is the finger pontoon attached to the main jetty?
It is pinned straight on, without brackets, beams or screws into timber. The floats of the finger fit into the same 50 cm grid as the main jetty and are joined with coupling pins and bolt sets. Main jetty and finger then form one continuous jetty.
You only need two tools: a rubber mallet and a pin spanner, €53.25 together. One float weighs 6.8 kg, so two people can add a finger without a crane. How it works in detail is explained in our guide Building a floating pontoon.
How wide is the berth between two fingers?
As wide as your boat plus room for fenders on both sides. Because the main jetty is built on a 50 cm grid, you can choose the spacing between fingers freely in half metres and change it later if a wider boat comes along. For the fenders, allow the width of the fender plus 10 to 15 cm on each side.
One finger takes a boat on each side. So two boats can share a finger, which saves material.
What does a jetty with finger pontoons cost?
A 1 × 5 m finger costs €1,272.50 net, fully connected. An example for two boats up to 7 m long: a 2 × 8 m main jetty along the bank for €3,931.50 and two 1 × 5 m fingers for €2,545 together. Add tools for €53.25, two jetty brackets on the bank for €270 and eight HDPE cross bollards for €300. That makes €7,099.75 net in total. Depending on the water, anchoring, freight and a separate pile or anchor at the end of each finger come on top.
Connecting a finger to the main jetty needs no extra parts; the parts list stays the same. So you simply add up the main jetty and the fingers separately. What a jetty generally costs per square metre is covered in our guide What does a floating pontoon cost?
What accessories does a finger pontoon need?
- Cross bollards: €37.50 in HDPE or €69.50 in stainless steel. They sit on the outside edge, in the joint between two edge floats. Allow two on the finger and two on the main jetty per berth.
- Side cleats: €24.75 for small boats, inflatables and kayaks.
- Fenders: long fender H27 for €65 or short fender H35 for €49.50 along the edge of the finger, so the hull does not chafe.
- Pile guide: from €175. With a 1 m wide finger, the end needs its own pile or anchor from a length of about 4 to 5 m in still water, and from about 3 m where there is current. We set the exact requirement in the quote.
You will find all parts under Railing and bollards and Accessories.
Do I need a permit for a finger pontoon?
The finger pontoon is part of your jetty, so if the jetty needs a permit, the finger belongs in the same application. Whether a permit is required depends on the country and the body of water. If you add fingers to an approved jetty later, you are altering the structure, so check with the responsible authority first. This is not legal advice. For the UK, the rules are set out in our guide Do I need permission for a pontoon in the UK?
Prices as per our price list of 01/10/2026. Prices may change. Before you buy, get a current, binding quote via the configurator or an enquiry.
Plan your jetty with fingers
Enter the length and width of your main jetty in the configurator and you will see the parts list and material price straight away. For the fingers, tell us which boats will lie alongside, with length, beam and weight. We will put main jetty, fingers and accessories together in one quote.