Early estimates of boat cost

Discussion in 'Boat Design' started by DCockey, May 24, 2017.

  1. DCockey
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    DCockey Senior Member

    Stephens and Waring are boat designers based in Camden, Maine. Their specialty is "spirit of tradition" sailboats but they have also designed power boats and overseen major restorations. They recently posted on their website an overview of two methods for early, rough, price estimates.

    We have evolved two methods to get at an early approximation for the cost of a new build: One, based on the cost of labor, plus a cost-of-materials factor. And, two, a flat price-per-pound ratio that expresses cost through a boat’s displacement.

    See their website for more information. Stephens Waring Yacht Design | Marine Engineering 105: Why My Boat Costs What It Costs? http://stephenswaring.com/marine-engineering-105-why-my-boat-costs-what-it-costs/

    Please note - their website is aimed at potential clients, not boat designers, and the subject is methods for providing rough cost estimates early in discussions between designers and clients, not for yards to use in bidding on a build. Also both methods rely heavily on experience.
     
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  2. Rurudyne
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    Rurudyne Senior Member

    I thought BOAT just meant "break out another thousand"?
     
  3. CDBarry
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    CDBarry Senior Member

    I have been surprised by this method for aluminum and steel commercial and quasi military boats: Calculate the OECD Compensated gross tonnage, multiply by about 40-50 mh per CGRT to get labor hours, multiply by about $60 / hr to get labor cost, double that to get materials and labor, add 10% for profit and actual cost for any unusual equipment like cranes or high performance engines, and that's a reasonable guess at price. Seems to work pretty well, oddly enough.
     
  4. Skyak
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    Skyak Senior Member

    It works for military boats because they are so highly specified. Just writing such a specification for a pleasure boat would add 30% to the cost. As DC said in the original post those are methods suggested to customers, not designers... and it is a bad idea at that. In today's world of dirt cheap computation it is easier and more accurate to start from the bill of materials then use the market values of comparable boats to guide size and finish...cramming more stuff in a smaller boat will cost more. The advantage is that all the components need to carry their own cost/value. Many of the highest quality components and materials justify their cost by saving weight. If you pay by weight you are going to end up with a useless fat tub made by ****** in Elbonia.
     
  5. Rurudyne
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    Rurudyne Senior Member

    You can float a lot on waist deep mud.
     
  6. DCockey
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    DCockey Senior Member

    The methods described by Stephens and Waring are for use long before there is a bill of materials. An experienced designer will select comparison boats with similar construction and equipment levels, and then adjust the estimates as appropriate. An example of the use of these methods would be if a customer approached a designer with a general description of the boat they are interested in and a cost limitation. How likely is the cost of the project to be within the cost limitation? Is it worthwhile to proceed with developing a set of requirements and a preliminary design to obtain a better cost estimate?
     
  7. Wynand N
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    Wynand N Retired Steelboatbuilder

    From my experience there is no ideal way of costing a boat to be built. Either the builder or the client gets burned either way.
    To give a building price based on weight, be it displacement tonnage, kilo or ponds may work if you have a consistent economic climate with stable prices and workforce. I had found that clients are not happy towards penalty clauses in a building contract, but so the builder because he has no control over long term stability of events etc. To name a few; acts of God, price rises, workers' strikes, below par performance of workers and costly rework if something went south to name but a few.

    The cost plus method, on the other hand, which was the way most of my boats were built, does solve some of the fixed price options. Client pays all expenses like for instance space, electricity, materials, consumables etc plus an agreed upon percentage markup added to these costs, which in effect is the gross profit margin of the builder. This safeguards the builder from unexpected price rises in materials.
    The labour is calculated on an hourly basis, but this is again very problematic for the client due to following uncertainties; does the builder bill for the correct hours worked, does the client pays for rework due to the builder's neglect, but worst of all, does the builder build at best possible pace and not force the built in an overrun?

    If a builder stays in a banana republic such as I do, where corruption is strife, monetary exchange rates that changes for the worse more times a day than women changes clothes, violent riots, stay-a-ways, union strikes for ridiculous wage increases are the order of the day both methods are very risky for both the builder and the client.

    At the end of the day boat building is a very risky affair unless you deal with a yard that has a rock solid reputation and production series of boats, but will also cost the client slightly more than he bargained for when taken delivery of his prized boat....and these are mainly GRP units.
    Custom boats such a one-off GRP, steel and aluminium are very risky to get build on a prescribed budget. My advice to the client, take the agreed upon cost and add 30-40% and that will probably be what you will be out of pocket with a custom built boat.
     
    Last edited: Jun 18, 2017
  8. CDBarry
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    CDBarry Senior Member

    Compensated tonnage isn't based on weight, it's internal volume with a compensation factor based on vessel type. There is no agreed upon factor for military small craft, so you have to use NCCV (non cargo carrying vessels) most of the time. Despite that, it generally works as a wild guess.
     
  9. Alik
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    Alik Senior Member

    We estimate cost of recreational boats in simplified way:
    1. Cost of structure - includes materials, labor, overheads. Is taken per 1kg of structure, say from 15-20USD for relatively simple FRP structure.
    2. Cost of machinery/engine - taken per horsepower, we derived the factors based on few projects.
    3. Cost of equipment - this is the most difficult part, as it can vary a lot. We used to take it per 1kg of equipment, including installation cost.
    4. Cost of interior - taken per 1m2 of room or per 1kg of outfit, depending on level of finishing.
    Summarizing 1 to 4 we get estimate of construction cost.
     

  10. Squidly-Diddly
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    Squidly-Diddly Senior Member

    Just weigh the blueprints.
     
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