Smallest possible mobo w. min. 8 berths/4 cabins.

Hugin

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Recently I have played around with some design and layout ideas for a mobo, which would bea suitable holiday boat for 2 boat-sharing families, the 3-generations extended family as well as for the charter market. IOW, the cheapest to buy/operate/maintain planing boat possible offering at least 8 full size berths in 4 cabins, 2 heads and enough entertaining area, that claustrophobia doesn’t immediately becomes the overriding theme.

I believe there is a market niche here that is not adequately served by existing models. My own extended family for one would be interested in such a boat if it existed. The charter market would obviously also love an affordable boat with private accommodations for 4 couples.

So I’ve been comparing dozens of layouts and measurements of existing boats. I’ve thrown in quite a few of my own unique space optimizing ideas….. and I’m now more than convinced that it is possible to design a planing mobo with a dry displacement around 22.000-24.000lbs, LOA of 45’-48’ and beam 13’ that fits the above description.

In fact I think it’s even possible to fit no less than 5 cabins (3 double/twin and 2 single), 2 decent sized heads, a large galley and an indoor/outdoor aft dinette seating up to 10. Plus an extra convertible dinette/double berth in the salon for a grand total of 10 full size berths in case a large number of guests decide to stay for the night.

The question is if something similar already exists and I just overlooked it? Anyone knows of one or more boat models that come close? Current or recent.

The smallest (lightest) true 3 cabin boat I can find is a Delta 40sw at 15.000lbs dry, but only one head.

ManoMarine 38.50 at 18.000lbs also has 3 cabins and the dinette converts to a (not very comfortable) double, so it’s a 6+2, but again with only one head

But once the requirement is 4 double cabins and preferably 2 heads then there seems to be very little on offer below 40-50.000lbs displacement.
Any suggestions?
 
It's only charter boats that seem to have a lot of cabins, most private owners want lots of saloon/cockpit space rather than cabin space.

.....hence the popularity of the extended cockpit/ deck saloon all on one level with patio doors that make it very convent to walk from inside the saloon out into that cockpit; an extended fly bridge roof over the cockpit making the whole thing even more practical in bad weather, or in the hot sun of the Med.

A boat stuffed full of cabins, at the expense of saloon/cockpit space, is simply not what a modern boater would want!
 
It's only charter boats that seem to have a lot of cabins

From what I have seen charter boats are mostly the same models as those in private ownership.... at least as far as the planing boats go. Canal and inland waterway boats is a different story, of course.

most private owners want lots of saloon/cockpit space rather than cabin space

I guess it depends how you use or intend to use the boat. Part of my point is that if you are financially limited to a boat around 10-12t then having 8 people on board for an extended weekend cruise is not even an option given the designs on offer. You need something like a 60´ if you are more than 6 people wantingh to share a boating holiday and then we are talking a completely different kind of money.

.....hence the popularity of the extended cockpit/ deck saloon all on one level with patio doors that make it very convent to walk from inside the saloon out into that cockpit

I agree with that, but does it necessarily have to be at the expense of comfortable overnight accommodation?

A boat stuffed full of cabins, at the expense of saloon/cockpit space, is simply not what a modern boater would want!

I also agree about the "at the expense of saloon/cockpit space" bit. But what if a 10-12t boat could provide both the 8 berths/4 cabins and a more than decent entertaining area on the main deck? That would open up possibilities for boat-sharing that are not on offer now below 60'. That's where I'm pointing.
 
10-12t boat ... 8 berths/4 cabins
...Doesn't sound attractive. 8 people occupying the space you have left over after building those 4 cabins sounds like hell to me and I think most of the market will feel the same. I'd love to see a sketch of the idea though because I'd be very happy be proved wrong here
 
I agree with JFM
IMO too much attention is given to how many cabins a boat has.
Obviously, it depends on how much you use/stay on the boat and if it for charter etc.
If you squeeze people into small cabins, the experience becomes more like "camping" than living.
Our boat is an example of the opposite that is being proposed here.
20m boats can easily accommodate 4 cabins an, indeed most do.
Our 20m boat has three huge luxurious cabins - non of which you would consider as "camping" cabins
We spend months at a time on the boat - she is a "home form home" and is just that - "a comfortable home"
We don't camp

Sorry, just my views
 
...Doesn't sound attractive. 8 people occupying the space you have left over after building those 4 cabins sounds like hell to me and I think most of the market will feel the same. I'd love to see a sketch of the idea though because I'd be very happy be proved wrong here

We stayed on ours a couple of weekends ago - the first of the season -and there was only 4 of us, and we were close to having to do 2 runs in a Sharan to get all our parephenalia on board. So accommodation may be one issue, storage for that many people will be as big, if not more of a headache....
 
We stayed on ours a couple of weekends ago - the first of the season -and there was only 4 of us, and we were close to having to do 2 runs in a Sharan to get all our parephenalia on board. So accommodation may be one issue, storage for that many people will be as big, if not more of a headache....

There are already Boats. Sailing Boats (charter version) and Catamarans, both of which cramp in accommodation. On a Mobo front Galeon back in 2002 produced an aft cabin 3/4 cabin boat (360 aft Cabin) At the time we thought it amazing....but few sold and it was quickly discontinued. All under 40ft. I have spent time on 5 bed charter sailing boats and you soon learn to love or hate each other.......

N.
 
If you squeeze people into small cabins, the experience becomes more like "camping" than living.
Our boat is an example of the opposite that is being proposed here.
I tend to agree with you but at the same time, I think the OP has a point. I'm sure its the same for many owners but when we invite friends or relatives on board, especially since we've been Med based, they tend to come mob handed and stay for several days so then the number of sleeping cabins does become a big issue. One big bugbear of mine is guest cabins with double beds because then effectively that cabin becomes a single berth cabin unless its occupied by a cohabiting couple. IMHO, boat builders could be a lot more imaginative about how they design cabins on boats. For starters all double berths should be able to be split into single berths and all crew cabins should be as accessible as the other cabins, similarly finished and with usable heads facilities. I would like to see fold down bunk berths offered in guest cabins where its possible (like on the sides of the forward cabin) and possibly moveable partitioning to convert one large cabin into 2 smaller ones. We looked at a boat last year which had a midships master cabin which could be partitioned into a smaller master cabin and occasional 2nd cabin with small bunk beds suitable for kids. Great idea if you regularly have kids or grandkids on your boat. Yes I recognise that living space is valuable and it shouldn't receive less priority than cabin space and nobody likes to feel overcrowded on their boats but sometimes you just need to sleep a lot of people
 
Mike, I agree 100%. You need a Squadron 78 Custom. My current boat has 3 cabins that are convertible - either a pair of twins or a double. Plus my crew cabin (which is fitted out in the same fabrics and woods as the owner's cabin) has a solid wood partition (in walnut so it looks like part of the boat) that allows it to convert into two small single cabins each with own access door from the corridor and each with access to a (shared, jack n jill)) shower room without passing through the other cabin
 
I can see there is widespread skepticism towards the idea of a relatively small Mobo with a lot of cabins and berths.... which is maybe not surprising. So I'll try to visualize the concept here. Unfortunately I am not a talented illustrator, so I will try to visualize it with a combination of words and pics/illustrations found on various websites.

Ethos 30.jpg

The first pic is of a little know Italian multi-purpose boat, Ethos 30. The important detail here is the door arrangement, which allows very easy and safe access to the front deck both from the helm (through the starboard folding door) as well as from the main deck/saloon in general (through the port folding door). This set up allows a full beam superstructure from the helm and all the way aft, adding approximately 2ft.(60cm) of useful width to the saloon as well as aft cockpit. That's a lot of extra entertaining area on the main deck for free

NordWest 430 Fly.jpg

Next illustration is the layout of NordWest 430 Flybridge. I would pretty much copy everything on the lower deck. 2 heads, a double and a twin cabin halfway tucked under the forward part of the saloon. Only change would be the bow cabin where the double berth would give way for 2 single berths pushed out against the hull sides, a partitioning wall between them and of course separate doors to the two cabins. These two cabins could be joined into a larger twin cabin by removing the partitioning wall. Since the boat I'm envisioning would be 5-6 feet longer than the NordWest the two midship cabins could be assigned a little extra floorspace to gain a sense of roominess.

Marex 375.jpg

Third illustration is from the still to be introduced Marex 375. This main deck layout shows two sitting areas, one inside and one in the aft cockpit. There is a partition between the two, I assume with some fold-away or roll-down (like the side-window in a car) window. The two sitting areas are something like 18ft. in length combined. 15ft. would be enough and both these sitting areas could still be converted to full-size double berths. I would move these groups to starboard and have a 2-seat helm bench forward of them leaving space for a large galley to port. I suggest installing a removable non-transparent partition between the 2 sitting areas instead of the before-mentioned glass partition. To port a double-folding (non-transparent) door completes the partitioning between what is usually considered saloon and aft cockpit. With this partitioning in place the aft cockpit becomes a very large and comfortable cabin with perfect privacy.... I even think it will be possible to shoe-horn a decent closet in to port. And before you ask how you can have an outdoor cabin.... please be patient, explanation follows

Aquado 35ST.jpg

The last pic is the Aquador 35ST. Here it is the extended roof over the aft cockpit which is important. These extended roofs are quite common on hard top boats; I just think it is particularly obvious on this model how the roof nicely covers the aft cockpit area. My idea is to install windows between the extended roof and the cockpit railing. These windows can swing up under the roof and/or roll down like over-sized car windows; creating an open aft cockpit when the weather permits or an indoor space at night and when the weather is unfavorable. Add a few curtains and the aft cockpit becomes the boat's 5th cabin... and by far the largest. Only downside is that there are something like 30ft to nearest toilet. The forward sitting group also converts to a double berth, but without the comforts of a private cabin.... a privacy curtain could make it an acceptable solution in a pinch. So sleeping accommodation for 10 (in a pinch); 8 of these distributed in 5 cabins.

I don't think this set up compromises the day-time entertaining areas. My calculations indicate the two sitting groups together could seat 12. Add 2 more on chairs/pouffs to port (aft cockpit part) and 2 on the helm bench and you have 16 people in the saloon/cockpit combo. I doubt more is needed.

I imagine the concept as a long (48'; hull +aft platform), relatively narrow (13ft) and light (~11t) boat

Hope it adds something to the discussion
 
Hugin, what you haven't mentioned is drives. All of the boats you have mentioned are sterndrive powered and yes this form of drive maximises accommodation space but sterndrives aren't really suitable for boats above 40-45ft in length because of their power limitations and arguably, slow speed handling issues. So what you're basically saying is that sterndrive powered boats give more accommodation than boats with other forms of drive. Well thats been true since sterndrives were invented. In fact that was one of the reasons they were invented in the first place. The real innovation would be how you could squeeze 4 - 5 cabins into a conventional shaftdrive boat of a similar size and designers have been trying and failing to do that for years
 
Hugin, what you haven't mentioned is drives. All of the boats you have mentioned are sterndrive powered

The Ethos boat is traditional single engine inboard. The NordWest 430 is available with pod drives and identical deck layout. The midship cabins are so far forward (basically below the helm) that I see no reason a V-drive solution or maybe even conventional straight shafts could not be possible. I think the real innovation is the arrangement with an indoor/outdoor multi-purpose aft cockpit and a partitioning between this cockpit and the saloon.
 
How about an aft cabin layout? 45 foot al la Brooms 450 or Atlantic 45. Two double single bunk cabins aft sharing one head. Move the master island double to the front. Another small double single bunk cabin opposite side to the galley, both front cabins sharing the front head...8 berths in 4 cabins.

There is an older broom monarch 12m on the Shannon with two cabins aft and the master cabin forward. One small double berth cabin (non island obviously) and one double bunk cabin. Both sharing a single head
 
Whopper, I like (some) aft cabin designs, especially Marex 370 is neat; but I think you will find that most here will argue a traditional aft cabin is a real killer as far as the day-time entertaining area goes. The just mentioned Marex 370 would be a point in case, barely 5-6 people fits in what is considered the main daytime living space. I would agree with those saying an aft cabin compromises day-use.
 
The Ethos boat is traditional single engine inboard.
OK point taken but I thought we were talking maximum cabins not maximum deck saloon space. In any case, the full beam saloon space is far from free especially in the land where this boat comes from as anyone familiar with stern to Med moorings will know. You have to walk the lazy lines all the way forward from the stern and lack of side decks makes this almost impossible. Agreed though that it might be a compromise worth making in cruising areas where alongside mooring is the norm. However, full width deck saloons or asymettric deck saloons are not a new idea

The NordWest 430 is available with pod drives and identical deck layout. The midship cabins are so far forward (basically below the helm) that I see no reason a V-drive solution or maybe even conventional straight shafts could not be possible. I think the real innovation is the arrangement with an indoor/outdoor multi-purpose aft cockpit and a partitioning between this cockpit and the saloon.
Yup the Nortwest 430 offers 3 cabins but so did other much older 42ft designs such as the Sealine F42/5 and Azimut 42 to name a couple and those were both conventional shaftdrive boats so I dont think the cabin layout of the N430 is anything special particularly considering it is sterndrive powered. Not sure what you mean by indoor/outdoor multi purpose cockpit
 
It's a good study IF you really want 10 people on 48 feet. But I just cannot see why you would. I think living on this would be hell. You'd be forever tripping over people and their geAr during the day, not to mention the 2 duvets, 8 pillows and sheets from the living space cabins, to be stored somewhere during the day. And two bathrooms with 10 peoples worth of towels. Honestly feels like hell.
As Deleted User says the absence of side decks doesn't work in med because you cannot moor. You need to be able to walk the lazy lines down the side decks
I doubt you can store all the food and glasses and plates for 10 people. And all the changes of towels
 
the full beam saloon space is far from free especially in the land where this boat comes from as anyone familiar with stern to Med moorings will know. You have to walk the lazy lines all the way forward from the stern and lack of side decks makes this almost impossible

I admit to be a bit ignorant about stern to moorings as all my boating experience is from the Baltic where bow to is the norm. Maybe there is an issue here, which could if not sink my ideas then limit their practical use. Can you or someone else explain me what "walk the lazy lines all the way forward from the stern" means exactly?

However, full width deck saloons or asymettric deck saloons are not a new idea
As far as I can see there are not many full width saloon boats above 30'-32' around, so maybe I am displaying out-of-the box thinking here:encouragement:

Not sure what you mean by indoor/outdoor multi purpose cockpit

Either I explained it in an incomprehensible way or you skipped the relevant paragraph. My ideas would allow the aft cockpit 3 different "modes"
1) As an open air dinette and entertaining area for up to 9-10 people
2) Same as above but now indoor as the cockpit is surrounded by fold-down windows (or similar) on three sides
3) Function as a spacious double cabin at night; again windows on three sides and a non-transparent partition towards the forward part of the saloon.

It is this multi-functionality - together with the full beam saloon - that makes the difference, so it is possible to have plenty of entertaining area during the day and 2-4 extra berths (with acceptable privacy) for the night.
 
It's a good study IF you really want 10 people on 48 feet. But I just cannot see why you would

Because that is the only economically viable road to share your boating with friends and the extended family. Your perspective is understandable in the sense you can afford a £2mio. boat. But for every person who can afford a £2mio. boat there are maybe 25 persons/families who can afford a £400.000 boat and maybe 100 persons/families who can afford a £200.000 boat. My thinking is that some of those who can afford the £400.000 boat might be interested in sharing their maritime experiences with friends and families also for the occasional extended weekend or even a week long holiday. And some of those 100 who can afford a £200.000 boat might want to pool their resources with another like-minded family so they can all enjoy the comfort of a £400.000 boat, sometimes with 2 families aboard, sometimes only with one family aboard. Simple boat-sharing (not to be confused with time-sharing)

I think living on this would be hell. You'd be forever tripping over people and their gear during the day, not to mention the 2 duvets, 8 pillows and sheets from the living space cabins, to be stored somewhere during the day. And two bathrooms with 10 peoples worth of towels. Honestly feels like hell.

All very true, but I fail to see the difference to a 30' single cabin, single bathroom boat with a family of 4-5 people aboard for a 2 week holiday. If anything the bigger boat with 8-10 people aboard would be much more comfortable than the smaller boat with 4-5 people aboard. I've tried the 2 week holiday in the small boat mentioned several times and it may be a little crowded but that is the reality of the masses..... and it's fun nevertheless. The more the merrier, a practical and affordable 8 berth boat could be the basis of some mightily fun days in my book.

Fjord 32.jpg

A Fjord 32, one very small bow double cabin, a midships dinette convertible to a double, an extremely small bathroom (more like a closet - shower completely useless), a small galley with a gas burner and a microscopic fridge; aft a decent sized cockpit. I know from experience it works for 4 people..... the larger boat I suggest would be pure and utter luxury in comparison, even with 8 people aboard.
 
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