Imagine you came across a hull in a field. It looked like a couple of 1970's / 1980's Australian models you were familiar with but the deck had been modified. For the purposes of identification you wanted to measure the LOA. It had a raked rudder extending beyond a raked stern and fair size bow rollers with the forestay attaching halfway along the roller.
Where would you measure from / to?
I'd go with tip of rudder to... end of bow roller? or where the deck ends at the bow under the bow roller? Anyone have knowledge on this?
It's a curly one, depending on who is doing the measurement is what determines how long it really is eg. A marina owner may well measure to total length from whatever is at the front to whatever is last at the back (swim platform?).
An insurance company may measure you at the max length to grab a few extra dollars for your premium, eg. a boat may actually measure at 28' but the company calls it an XYZ 30.
The US Coast Guard defines it like this "Overall Length - The horizontal distance of the hull between the foremost part of the stem and the
aftermost part of the stern, excluding fittings and attachments." This one I think is the correct and fair way of measuring.
So this would be for identification purposes rather than berthing, insurance or other. So if the designer calls it a 30 or a 33 or a 37 and the stated LOA is that number give or take a handful of inches, where is the designer intending you measure from and to?
Usually from the most forward part of the permanent hull structure to the most aft permanent part of the hull, sometimes referred to as LOD (length on deck).
Not that straightforward Rog. An S&S34 by the specs is 33' 6 5/8". As built by Swarbricks 33' 1" as they changed the bow.
I suspect other boats might be as varied in their measurements.
Select to expand quoteLooseChange said..
Usually from the most forward part of the permanent hull structure to the most aft permanent part of the hull, sometimes referred to as LOD (length on deck).
This is how it's done for survey purposes and for fishing vessel licensing. Amateur boats the figures are often rounded out, shorter or longer and in metric or imperial to make the name! Who wants to look at an SS33.5.
