36' x 16' Cat Hull for Tiny House Project - Need Help Please :)

Good info Richard . . :)

Here's a view on the hull...

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And here's a brochure, page 6 below...

Catalac_10M6.jpg


Don't see the built in transom steps though, but this could be a modification . . ?

It seems standard equipped with a stainless stern ladder, the hulls look the same . . :cool:

Good luck !
 
UpOnStands is right, the bow was low weight deck area (veranda for the tiny house), then one story house, then mid center a small two story house, aft was low weight cockpit area but also two 18 HP diesels + drive systems, so one story house there I would suggest. And all the heavy stuff as low as possible in the length center of the boat, all weight equally divided from port to starboard, and fixed but still shiftable to trim the boat level.

All the one story house roof areas could double as terrace areas for lounging / partying / gardening in pots / etc. etc.

But as this is a boat it's all about flotation and stability, so not to many people on the roof, and keep them divided over the whole boat at all times...

woonboot-1988.jpeg

Best build the house afloat I think, so you can guard the overall balance during the build process.

Good luck !
 
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Need to have an idea of what the boat presently weighs, as is, before it is possible to know how much more can be added to get to a figure roughly equivalent to what the original displacement as designed, was. That is detailed above.
 
The original design was calculated for a given minimum freeboard that would give minimum security according to the navigation conditions of the original project. If these conditions are to change, the minimum freeboard can be reduced. Once this value is determined, the hydrostatic values will determine the maximum total weight of the vessel at full load. The OP should weigh the boat as it is now to be able to know exactly the total weight that he can add.
 
The original design was calculated for a given minimum freeboard that would give minimum security according to the navigation conditions of the original project. If these conditions are to change, the minimum freeboard can be reduced. Once this value is determined, the hydrostatic values will determine the maximum total weight of the vessel at full load. The OP should weigh the boat as it is now to be able to know exactly the total weight that he can add.
Thanks for your time and efforts!!
 
before anything, is the hull now sitting on the concrete blocks as shown in your first photo?
If so, definitely reblock the boat - soil looks very soft and replace the hollow concrete blocks with something solid.

First impression is that the front 1/4 -1/3 of the boat must be veranda with nothing heavy on it.

As TANSL notes, you will need the lines to get the best results.
Here is one suggestion
run a horizontal chalk line in line with the bottom of the stern and parallel to the hull and mark off 3 foot intervals running forward.
run perpendicular lines and then measure lateral offsets and heights at the chine line

edit for Richard; were any of the Catalac 34's sold as power boats?
Thanks for your time and efforts!!
 
So, IF that is the hull you have and the weight is 11 000 pounds ( 5.5 tons ), you could almost double that if this is to become a floathome to be kept permanently in extremely protected waters. "Almost double" would be the gross weight with all your friends and provisions on board, tanks full, snow on the roof, etc. But you couldn't go anywhere with it... isn't that what a boat is for, to go places? Why not make a little live-a-board out of it and enjoy the boat as a boat, not a floathome?
I'm sure you've got your reasons and it's a rhetorical question but I think you're crazy to waste a perfectly good, navigable hull, building as big a "Tiny House" as possible on it.
 
Kind of late but on a somewhat? related topic
If you have a boat and want to 'guesstimate' the displacement you can use the Block Coefficient (Cb). The block coefficient can vary from 0.33 for fine ended hulls like sail vessels, rowing shells, etc up to 0.95+ for full bodied hulls like barges etc. (note: for sail vessels I take the draft as measured to the fairbody or rabbet line. If you include draft to the keel, the Cb will be less )
To obtain the volume of displacement Multiply the LWL (waterline length)x Bwl (Waterline beam) x Draft x Cb
(I used US/Imperial but S.I.(metric) works as well
Using this Catamaran as an example 'spec sheet' I would guess the Cb at 0.36 and the Bwl each hull at 3.5'.... so in this case:
27.0 x 3.5 x 2.75' x 0.36 = 93.55 cu.ft. x 2 = 187.1 cu ft. (both hulls).
In sea-water 187.1 x 64 = 11,975 lb (displacement)
The brochure (above) you can get the weight (displacement) at 5.6 tonnes = 5600 kg = 12,400 lb-approx..... so I guess we are kind of close.
As noted, this is a guesstimate.. so what's the use???
Sometimes you need a rough boat weight for lifting apparatus (Travelift), trailers, permits, etc. and and some owners have no idea of their boat's weight*: A guesstimate is a place to start .
PS:* Gross tonnage and Net Registered Tonnage as listed in a boat's documents/registry are a measure of internal volume (100 cu.ft./ton) and nothing to do with vessel displacement (weight)
 
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