Trailer Advice and Sizing Guide

Trailer Advice and Sizing Guide

Choosing the correct trailer is essential for safe towing, reliable launching and long-term durability. Trailer selection depends on several key factors including boat type, weight, dimensions and how the trailer will be used. If any of these are mismatched, it can lead to premature wear, poor handling or avoidable safety issues.

Boat type and hull support

Different hull types require different forms of support. RIBs, hard boats and dinghies are typically best suited to roller support, which aids launch and recovery. Wooden boats often require additional keel support with stabilising bunks, while inflatables and small SIBs are generally better supported on bunked trailers. Correct support ensures the hull is properly carried without point loading or distortion.

Boat length and contact points

Trailer sizing is not based solely on overall length. While LOA is a useful reference, correct trailer fit depends on the distance between the bow eye and the transom, as these are the primary contact points with the trailer. This measurement allows the trailer to be set up correctly for weight distribution and nose weight.

Boat weight and load calculation

Accurate weight is critical. Trailer capacity must account for the combined weight of the boat, engine, fuel and onboard equipment. A common rule of thumb is to add ten percent to the estimated boat and engine weight to allow for gear and margin. Underestimating weight is one of the most common causes of trailer issues.

Braked or unbraked trailers

UK regulations require trailers over 750kg gross weight to be braked. Below this threshold, an unbraked trailer may be suitable, provided towing limits and vehicle restrictions are met. Selecting the correct braking configuration is both a legal and safety consideration.

Single or twin axle trailers

Single axle trailers are suitable for many smaller and mid-sized boats and offer simplicity and manoeuvrability. Heavier boats may require a twin axle trailer to safely distribute load and improve stability when towing. Axle configuration should always reflect actual loaded weight rather than estimated size alone.

Rollers or bunks

Roller trailers are generally easier for launch and recovery, particularly on shallow or uneven slipways. Bunks offer broader support and are often preferred for lighter boats or inflatables. The correct choice depends on hull shape, launch conditions and frequency of use.

Getting the setup right

Even the correct trailer needs to be set up properly. Nose weight, axle position, winch height and hull support all play a role in towing stability and ease of use. Poor setup can cause snaking, uneven tyre wear or difficulty launching and recovering.

If you are unsure which trailer is right for your boat, or would like advice on setup, upgrades or future changes, speak to the team and we will guide you through the options.

If your boat or usage has changed, upgrading your trailer may be appropriate. In some cases, part exchange may be possible, subject to inspection.