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Floatation regs

Home Forums Research Engineering Floatation regs

This topic contains 5 replies, has 3 voices, and was last updated by Profile photo of  Anonymous 1 year, 7 months ago.

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    Ocean (or anyone else), do you know of any interesting regulations regarding floation in home-built boats? For instance, do RIB hulls need partioning like regular hulls (should) have, or do they just go totally flat and sink the very first rock they hit? Can i wrap a RIB hull in metal and it be a metal hull? Is there a reg for the amount of styrofoam, or pour-in high-density expando-foam, used in non-partionioned hulls? Can a long non-partitioned rigid hull use multiple air inflation bags inside instead of foam? Do loss-of-pressure sensors, or water-presence sensors matter as far as getting a 32ft hull tagged by the state? Is there a certain reserve bouyancy requirement in “the fine print” for certain boats? For my lil pontoon boat, i built in bulkheads every 4ft, and access ports (3/4″ pipe fitting) at each end of each section, but is there a regulation for that?
    I saw an aluminum boat in the scrap yard today, had the boat builder’s commercial name on it in big bold lettering. I won’t say the name for legal reasons, but it was meant to bring “durable”, “tough”, “action” to mind. As i approached the bow, i thought it looked like a design that would slam badly in waves. Looking further along the bottom, it was covered in fiberglass patches, aluminum patches, bondo, and slathered in silicone caulk along the keel.

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    It is my understanding that if a homemade boat is built “for pleasure use”, there are no CG regulation regarding the “method” of construction. So I guess you can built as you want.

    The question here is why built your living quarters from scratch at such small entry level seasteading? (other than few flotation support modules for your living quarters). It doesn’t make sense to invest money and time (otherwise the most precious commodity around) into something that you can buy used, but ready to use, for far less that what you will pay for materials only.

    But it is your time & your money…

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    Ocean, the price question is as it always was: i don’t want a monohull, i want to be able to build a boat on my boat, and i see zero boats for sale.
    Monohulls are too unstable, and don’t lend themselves to getting wide very cheaply. If i want to make more boat (for fun or profit), i need flat work space, at least a 12ft wide space to make 4ft wide hulls on, at least 2/3 as long as the hull section i want to make. A oversized pontoon boat seems reasonable to get off land with, and i suspect pontoon boat types are easiest to raft together. I am thinking 3ft diameter steel pontoons, in 16ft sections for me to easily transport, under $30 per basic foot of length, and 200lbs floatation per foot to 50% waterline. Like i said before, i already have enough steel deck, it’s sitting in the driveway. And one of my rust experiments has not rusted for at least 5 years now, outlasting every rust inhibiting paint i have tried, so steel is a viable option.
    Since i can make the boat in any way i want, as a pleasure boat for myself, the only remaining issue is what’s the minimum requirements for living comfortably in 10ft waves 3 miles from shore. Obviously, i am not thinking in terms of 5000 year old technology. I just hope those with the power to grant hull numbers and do inspections aren’t stuck in ancient times.

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    The concept of “living comfortably” at sea is very relative, Kat. For example, I am “comfortable” on any size boat that I feel safe on. To me, comfort = safety.

    If you won’t feel safe out there, no matter how big the seastead, you won’t be “comfy”.

    On the other hand, you have to realize that you are not talking about seasteading. When you say “I want to live 3 miles offshore on a boat that I built”, you are talking about living aboard. In this case, my advice to you is to ask yourself why 3 miles and why not 500 yards? What’s the difference? After all, the further you are from shore the more money is gonna cost you to live there.

    As for the the rest, it’s all up to you since you are the only one who knows your “comfort zone”.

    If I’d have to live aboard again (by myself), I’d do it in the Keys, on a 30′ sailboat, anchored closed to shore.


    A small boat is comfy almost nowhere except on the calm watersurface of a inland water channel.
    A normal sized ship is comfy in any bay where large ocean waves of 100m wavelength have no access.
    A Maersk triple E ship starts to enter the size class where it becomes comfy everywhere on the world oceans because ANY wave is small compared to the ship and the ship will not track ANY wave that occurs on the ocean.
    Being Comfy should be defined as “allowing a normal workday no perceptible movement just like on land – living space suitable for general population…no sea related hardship to experience”

    Scale influences also the economics, ship sized economics is different to boater scale economics. A living space the size of Empire State Building has its own shopping mall, cinema, so the “distance to land” becomes much less important. The distance becomes also less important if the “means of transport” is a “fast ferry” that you can take in suit and tie and have a breakfeast on the trip instead of a small open boat with spray all over you…

    What concerns transport cost in fact it will cost more in logistic effort and time to deliver a container of grocery store to a building in the center of Manhatten in the morning traffic, than to deliver the same container to a floating living space 5 miles offshore.

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    Ocean, good points, but like Ellmer has said: noise and eye pollution. And a big concern of mine, since i have heard the locals out shooting for hours this morning: the distance a bullet will travel. A mile, the distance number Ellmer has mentioned, is nothing to bullet travel or a cow’s noisey bellow. And on the local lake teens are known to use other people’s boats as jump ramps, even if the other boat owners are on the boats at the time (a guy was killed a few yrs ago here when a teen on a skidoo went right thru the captain’s console, while the guy was sitting there). Otherwise, sure, sheltered among the islands in shallow water is going to be less cost in a basic bathtub than out on the ocean. But if you allow for those idiots and pollution i mentioned, you find yourself out away from the islands, already on 5ft tall anti-skidoo stilts, and adding heave plates becomes a small (and beneficial) portion of the overall cost. But in good weather, and no one around, parked among the islands sounds wonderful. But a storm surge going over the island and turning trees into shrapnel headed towards your boat, not so good.
    Ellmer, the Maersk triple E ships are as wide as wave-lengths. I had a pic of the side to side rocking throwing containers off the ship on the site i took down. Even going head-on thru some waves can set up a sideways oscillation in the hull that throws containers. It is still a bathtub shape in the wave zone, period.

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