Boat measurements

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Gordon J

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Didi Mau
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Currently looking for next boat
I have a question about the measurements. My Ocean Alexander 456, is 45.5 feet long on the deck. From stem to the end of the swim platform it is about 53 feet. My previous boat, A sailboat, was a beneteau423. It's length it over all was 43'2". That 43'2" was measured from the tip of the bow roller to the edge of the swim platform.

Is it normal to measure trawlers only on the deck and sailboats overall?

Gordon
 
On trawlers it can vary by manufacturer. Mine is 45' not including the bow sprit and swim platform. It's listed as a 45' model, and both the bow sprit and swim platform were options. So I guess the manufacturer viewed the size as the minimum overall length.

Ted
 
My boat has a 47'6" hull length, and is 53'4" overall length

When it was made by Bayliner the model was 4788

When the exact same boat was made by Meridian it was a 490
 
Our OA 440 is 43'9" on deck. The anchor pulpit and swim platform are in addition. We pay for 48' in the winter storage building, 44' at some marinas...46 at others (add the swim platform). So far none have hit us up for the six feet added by the dink that is horizontal on the Nick Jackson davit. Most newer power boats seem to have the swim platform included.
 
Without trying to insult anyone, but they are 2 different measurements....length on deck and length overall.

And no, not measured differently, both types have both measurements.

A difference though is..... LOA will change with anchors and davits. So LOA isnt used a lot except at marinas charging for space, where LOD probably never changes.

Often either one is used for manufacturer model names, and either thrown around without regard to labeling, and somtimes argued with dockmasters when paying a transient bill.... :)
 
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Marinas expect to be paid by the actual measurement overall. That's the tip of the anchor to the back of the swim platform or the dinghy, whichever is longest.

My boat was in production for about fifteen years. For the first ten or so, it was designated as a 28'. That's what my documentation paper lists it as. At some point, they changed it to 31' without changing the design of the boat.

I expect that if I took a tape to it, it would measure about 31'. I've never done that.

To answer your question directly, it's common to measure all boats at the longest point (LOA) but this doesn't always match the model number.
 
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In the official world of boat measurements either for sail boat/power boat commercial or pleasure it's as follows:

LWL: is length of your boat at the waterline
LOA: is the "length overall". Measured from the aft most point on the boat to the forward most point on the boat not including things like railings, fixtures or pulpits.
LOD: is a measurement not normally shown but is essentially the "length on deck" which can be shorter then the LOA measurement if you have a forward sloped transom.

As above to note, the LOA should never include any fittings it is the actual hull itself measurement, I do note how ever that many brokers/advertisers quite often show the LOA as including things like bow extended rollers/stern platforms etc, and in some cases the push-pits/pulpits, on the vessels documents how ever it's referring to the above(LWL/LOA Descriptions)

Cheers Steve
 
I have a question about the measurements. My Ocean Alexander 456, is 45.5 feet long on the deck. From stem to the end of the swim platform it is about 53 feet.

Is it normal to measure trawlers only on the deck and sailboats overall?


As others have noted, model name (456) and actual LOA (~53') are often completely separate concepts, latter including swim platforms, etc.

OA very likely publishes exact numbers, and LOA will be on your CG paperwork, if you're documented.

Another example, ours are 42 and 46.2' respectively -- but then I also have to add some for our dinghy hanging off the stern -- so for marinas, we're usually 48'. And it usually pays to be straight with marinas, given the consequences of potentially being assigned to a space that's too small.

-Chris
 
When at a marina some folks gave the waterline length , instead of the LOA.

And when using a tape measure we always gave folks the option to remove the dink, and davits and bow rollers, and anchors.
 
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