Estimating displacement, payload and increase in risk

Estimating displacement roughly from length and beam is possible;

the payload comes to around twenty per cent,

and overloading beyond it is an increase in risk.

The estimate is no substitute for actually weighing the boat, but it does give you the right order of magnitude. The exact figure is in your boat papers or in the builder's documentation, and for craning and trailering you need the real figure, not the estimate.

Overloading is an underrated risk. An overloaded boat sits deeper in the water, responds more sluggishly and loses freeboard. In extreme cases stability itself is compromised, and at that point it is no longer a question of comfort but of capsizing.

In insurance terms, exceeding the permitted number of people or the permitted payload is a breach of your obligations under the policy. If you are out with twelve people on a six-person boat and you capsize, you should expect the settlement to be reduced, whatever your tariff.

Worked out for your type of boat

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