Q&A: How can I get the actual weight of my boat?

• Wednesday, 11 June 2008
• Dan Foley
• 0 Comments

Q: How do you get an idea of the actual weight of your boat? A friend got put on a weighbridge by police and failed much to his surprise; apparently this was down to smaller items on the boat adding to the accumulative weight.

A: The weight of a boat can generally be regarded as the same as its displacement. Confusingly, there are many different types of displacement. Displacement is increasingly defined as the Light Ship Weight (LSW) which is the weight of the boat as it comes out of the factory with no additional options, gear, fluids or supplies on board. Exactly what is included is not exactly defined and varies both sides of the Atlantic.

For trailing purposes you need to know the gross (total) weight. This involves adding the Light Ship Weight to the payload – the total of everything carried on board. To calculate this figure for your boat use Yachting Monthly's displacement calculator, devised by expert Nigel Calder’, to add up the extras.

There’s useful information on how much to add for stores and extra equipment you may have forgotten, such as power thrusters and ground tackle.

A list of UK weighbridges is also available, though to get to one you’ll obviously have to tow your boat so risk breaking the law!