Cabin Design Must-Haves

[Sunset]

Charlie I see your back in Texas. I haven't seen you on the B&B forum for a while.
I saw this tread on boat size and thought it was interesting. I started with Graham with the hopes of building a 32 catketch, then dropped the length to 25 then bumped it up to 26 and settled in at 28. We sold our Belhaven to finance the start of this project. I bout drove Graham nuts for year. Anyway we are now building her. I have the temporary frames up along with the stem and keel batten nearly ready for the start of the cypress planks.
Graham is leaving most of the interior layout to me other than structural bulkheads. So I have been trying to glean as much from folks that are out there doing cruising and living on their boats as to what makes a comfortable boat.
If you get the time, or anyone else for that matter please name your top five necessity's for a boat being out there 6 months of the year.

Scott

[Captain Smollett]

please name your top five necessity's for a boat being out there 6 months of the year.

Out there?  Is this with significant percentage of time offshore?  Making multi-day passages even if inshore?

If so, here are some thoughts on necessities that I have (in no particular order).  This might seem like a 'magazine answer,' but these are my thoughts based on what we've experienced and have changed or want to change on our own boat.

Also, I'm assuming since your post mentioned building your interior that you are specifically asking about below.

(1) Absolutely MUST have accommodations for the crew to get rest.  The bunks/settees/whatever need to be comfortable "to you" and if offshore (or sleeping underway at all), should be equipped with lee cloths or similar.

If someone in the crew cannot sleep with any light, for example, this should be well thought out - good curtains (so they can sleep during the day if need be), well planned lighting so on-watch crew can get work done without disturbing them, etc.

Tools and whatevers needed to operate the boat need to be accessible so as to not disturb the off-watch crew.  See #5.

My #1 necessity is REST.

(2) Good hand-holds below.  However easy it seems to move around the boat in the slip, underway it's a whole different ballgame.  A lot of production boats are missing this.  We have such a gap in the Alberg 30 that we are addressing, and doing so without causing other problems in the cabin took a bit of planning.

One hand for you, one for the ship applies even below...at least I've found this to be true.

(3) A galley design that works for you to (a) safely prepare meals underway (possibly without disturbing sleeping crew if that applies), (b) quickly and easily get to snacks and light meal ingredients so the on-watch crew can do this without compromising "proper lookout."  (Recall the tragedy of the Melinda Lee happened to occur while the Mom, on watch, was below making a sandwich).

(4) Water management...meaning, getting below when it's wet outside without soaking everything in the cabin.  This is harder to manage than it seems, at least it has been for us.

(5) A place for everything, and everything in its place.  Seems trite, but especially on small boats, the use of space must be maximized.  We get bad about leaving things out, and have paid the price occasionally - a broken galley water pump handle when we heeled over once, for example.

On a small sailfar size boat, it's hard to have everything stored where you don't have to dig a bunch of stuff out to get to that one thing you need.  Maybe there's no way around this to a point, but try to minimize it.  Small bins (like tupperware, rubbermaid and lock-it where water tightness is needed) have helped us.  A biggish locker just full of 'poop' doesn't work...at least for us.

On that note, don't ignore ANY potential storage space.  For example, a small space under the companionway steps could be used to store pencils or some such.  It's my belief that that is ONE of the reasons so many people think you need 45 ft or more to cruise comfortably...because there's a LOT of wasted space on too many boats. Lin and Larry have published some novel storage ideas that are worth checking out if you have not seen them yet.

That's my list of 5 Cabin "Necessities."  They are all interconnected.  If you are cruising solo, maybe you don't have to worry about getting your sleeping crewmate soaked when you go below to grab an apple on a rainy night...but then again, you won't like that wet bed in the morning much, either.   ;D

[CharlieJ]

please name your top five necessity's for a boat being out there 6 months of the year.

If someone in the crew cannot sleep with any light, for example, this should be well thought out - good curtains (so they can sleep during the day if need be), well planned lighting so on-watch crew can get work done without disturbing them, etc.


(2) Good hand-holds below.  However easy it seems to move around the boat in the slip, underway it's a whole different ballgame.  A lot of production boats are missing this.  We have such a gap in the Alberg 30 that we are addressing, and doing so without causing other problems in the cabin took a bit of planning.

One hand for you, one for the ship applies even below...at least I've found this to be true.


(

I've found that offshore, after a while, dark doesn't matter much- sleep comes!

On the hand holds- ABSOLUTELY. Laura was slightly injured on the 41 footer she did a delivery on because she COULD NOT REACH the handholds!!! The boat had too much head room and a 6 footer could reach, but Laura at 5'2" got flung across the cabin. They were in 16-18 foot seas and 35-40 knot winds, a day off the Texas coast.

[JWalker]

Grog to Capt Smollett for water management....MUCH more difficult than I thought....hanging locker by the companionway steps...and a shower pan at the base of the companionway steps would be nice.......when we come in wet......its everywhere. :(

[Captain Smollett]

Split this topic off from the Thoughts on Boat Size discussion so it could have it's own thread.


Charlie, you are right about the light, and perhaps that was a poor example.  What I was trying to say was that sleeping arrangement design should, where possible, take into account whatever habits or idiosyncrasies exist in the individual crew.

My example was merely to show how "canned" design ideas may not work very well with specific crew members.

Another example comes straight from our own experience.  My wife's sleep is easily disturbed by sounds...she's a VERY light sleeper.  And, it does not matter how tired she is, as she can attest to poor rest following many 36+ hour work days.

It does not have to be loud, just "different."

While this can be a HUGE advantage at sea where one must be really in tune with the boat, it does make her getting adequate rest a challenge sometimes.  As such, I think it's important to modify our cabin and sailing procedures so that the boat can be operated with minimal 'excess' noise...such as "rumaging around cluttered lockers" looking for a spare flashlight, etc.

I could think of a laundry list of things this could apply to.  I think with the opportunity to build a cabin from scratch, one could maximize this kind of 'creature comfort' and you hardly see it mentioned...this "personal" approach vice "rules of thumb"...in cabin design discussions.

[Sunset]

I have spent a token amount of time on my 19 foot Belhaven over the last 6 years. Two week at a time maybe a dozen times and probably 300 nights total. My Belhaven had no standing headroom, a limited galley, portapotty and limited storage. For a 19 foot boat that was very easy to setup from the trailer, I haven't seen any I liked any better. But I know there's a huge difference in spending two weeks and six months.
My wife and I are planning to keep this boat at Kentucky Lake during the summer and fall of the year while we help out with our parants. After Chrismas head down the Ten-Tom to the Gulf and south Florida and be-on for the rest of the cold weather. We'll head back as the normal flooding of our river systems permits in late spring.
I promised her two nights a week at a marina to fuel up, pump out, fill water tanks and a long hot shower.

So that's a short outline of how we will use this boat. Now that brings me to the cabin, She wants standing head room, a nice galley with oven, double sink, a shower, a comfortable mattress in the V berth area and marine ac that can be used at the dock. A lot of stuff to get in a 28 footer. We are planning to make the boat sleep two comfortably and with some effort two more guests but primarily a two person boat. I had thought of the handrails in the galley and head but hadn't really concedered them else where in the cabin. Sounds like a smart thing to put them along the the cabin roof also. The boat is a little beamy for a 28 nearly 10 feet, this should help with these comforts but will make the action of the boat a little quicker so plenty of hand rails would be nice, thanks I'll keep that in mind.

I plan to take a lot of time planning out the cabinetry for storage and ease of use. A well insulated top loading ice box with a refrigeration plate, so we can use ether ice or 12v or shore power.

The deck and cabin are going to be foam cored to try to cut down on condensation. I am going to use newfound metals ports and plan on putting a hatch in the v berth, salon, and a small one over the galley for ventilation. I have been thinking of adding another small one in the head also. My brother is in the keys now on a 25 foot Coronado and they are fighting condensation. Hopefully with foam cored topsides and plenty of ventilation the wet stuff will be held down. Any one got any other thoughts on this?

I won't be turning the hull over to start on the inside till summer so I be picking every willing persons brain on cabin layout.

Scott

[Captain Smollett]

She wants standing head room, a nice galley with oven, double sink, a shower, a comfortable mattress in the V berth area and marine ac that can be used at the dock. A lot of stuff to get in a 28 footer.

You are not kidding that's a lot for a 28.

Couple of thoughts just to consider.

(1) Please give serious thought to the shower.  All they do is waste water and increase complexity.

The pump-up sprayers work wonderfully.  Two people can take a comfortable shower apiece on less than two gallons of water.  No running water to plumb, no built in water heater, etc.  You heat up 2-3 quarts of water to boiling on the stove, mix in the sprayer container to make 2 gallons and go to it.

There's also the sun showers, which work great.  Ours holds again 2 gallons, and if you are where the sun can heat the water, so much the better.  They get almost too hot.

Sponge bathing and the 'baby wipe' method are good alternatives, too.

Compare:

We were a family of four living aboard and used less than 30 gallons of water per month out of our tank.  I know another set of folks with a shower on board that used 120 gallons per week.

(2) Double sink?  Wow.  Why?   ;)

Think about the idea of "wasted space" I mentioned earlier.  There are ways around needing a double sink that make having one wasted effort.

(3) Oven?  Some personal preference here, but...Dutch ovens and pressure cookers both provide good alternatives.  A land-based friend of mine told me just yesterday that he has gone "Dutch Oven" for all baking and has done so for over a year.  He loves it.  (He has a wife and four children).

Incidentally, his comment on the garden sprayer shower method was equally positive.  He had his teen age daughters using the method and THEY reported "no loss of comfort, nothing missed over 'regular' showers."

(4) V berth for sleeping is great in the slip, but does not work well at all underway.  The motion and noise is worse.  So, however comfortable you make the v-berth cushions, the main cabin settee cushions (and arrangements in general) should be equally so.


As the saying goes, your mileage may vary on all of this, but those are my thoughts...coming at it from

(a) KISS is better perspective and
(b) these less "house" based solutions do NOT cost in comfort.

The conventional approach is to mimic the house in the boat....that's what I hear when "shower," "double sink" and "oven" are mentioned by folks as must-haves on a boat.

A boat is NOT a house.  You/she/"they"   ;)  have to think a little differently.

Trying to 'fit' all the traditional 'amenities' of home into a small boat, a 28 footer for example, is doomed to failure if the history of others is any guide.  I fear you will forever walk the "10 foot itis" treadmill of feeling the need for a bigger boat with MORE amenities.

House solutions are square pegs to the round holes found on board.  Contrary to popular belief, that does NOT mean that the "boat ways of doing things" (more in particular the SMALL, KISS boat ways of doing things) mean less comfort or a less enjoyable lifestyle.

In three years of living aboard with no refrigeration, no running water, no water heater, a small single galley sink and no 'oven,' I can honestly say I didn't feel deprived of "lifestyle" because of these things.

My wife missed a bath tub on occasion.

Finally, "marine air conditioners" can be unduly expensive.  There are less burdensome alternatives, and underway or on the move, you really won't need one that much.  The only time you'll need feel the need is those two nights in the marina....that just smacks of a mighty big investment (in money, space and 'hassle' aboard) for something used at most two nights per week.

Consider a hatch scoop/wind sail for the fore hatch.  Those things are unbelievably effective.


Your boat, your choices...so, I hope you get the spirit of my writing this...just sharing thoughts.

[rorik]

FWIW (I live on my Cape Dory 28), ovens are nice, but you can do almost as much with a good pressure cooker. Fagor even has a cookbook - "Tastefully Under Pressure" - www.fagoramerica.com. Granted, I have only me to feed, but a Fagor 6qt pressure cooker, a 3 qt sauce pan and a 1-1/2 qt sauce pan and a small kettle have done everything for the last year and a half. As long as the sink is big enough to wash up in, a double sink is overkill. That extra space could be used for food, a bigger, better insulated ice box, etc. Shower? I wish... but by the time I get tools, books, clothes, spares and still have enough room to turn around without assistance, a plumbed in heated shower is out of the question.

[CharlieJ]

I whole heartedly concur.. I'd like to enlarge on the shower. On a small boat (less than about 40 feet) a shower is a simple invitation to mold and mildew, plus they are MESSY. I use the pump up shower from Duckworks.It's black, holds two gallons and lives in the cockpit. Showers are done there, blocking view with towels as needed. It's also used for rinsing dishes after washing in the single removable sink. When it's hot, it's nice to be in the cockpit, under the bimini or awning.

When actively cruising, I've never ever felt the need for an AC- we use a 12 volt fan and a windscoop. I keep a 110 volt fan aboard for dockside use.  Of course I don't use AC at home either so I'm used to it. But they are power hungry, take an inordinate amount of space  to store, and are expensive.

Laura baked bread, biscuits, cakes, and canned meats all in a pressure cooker. Ovens are nice, but not required. Here's pics of some of the meats, and the pressure cooker they were done in-





After several years of full time being aboard, and something like 10,000 total miles ( three cruises), I can say it's all worked fine.

[Sunset]

I agree almost totally to what your saying Captain. Also thanks for input, I like how you said it's a boat not a house. Very true! But I must find a way to get as far as way from the pop-up camper way of thinking as possable. My wife puts up with a lot of stuff from me but if she's not somewhat comfortable I end up being the one not so happy somehow.

My brother gave me an idea on the hot showers with privacy. He said why not buy 3 solar showers. Have a place on the cabin roof for one at a time. Put a quick disconnect on them where that hot water can be directed straight to the shower area. When that 4 gallons is depleted in a few days just simply change it out for another. They can be refilled at our marina visits. The up side is hot shower without any hot water heater and the privacy of the head area. The down side is finding storage area for the two extras until needed. I like cockpit showers my self after dark or in an area without an audience. She does not share this view with me at all.

As for the sink I already explained to her that it would be a lot smaller than the size she's used to.  ;DI all ready said no to the garbage disposal ;D

The marine air I really think I can convince her is not needed, especially the time of year we'll be using the boat. More than likely it be heat that is needed more than AC.
Leaving KY Lake in January is going to be cold. We could use a small ceramic heater at marina stops along the Tenn-Tom but underway is a differant story.
I have not investgated if a heater core can be run from my Beta 20 or not for heat while underway. Everyone I have talked to said unless you get a north wind on the Tenn-Tom I'll be motoring the whole way anyway.

I plan at this point to have a manual pump on the sinks to help with water conservation. This is subject to change.

Its funny I am the one that wants the gimbled stove with oven. I love to bake all kinds of bread. The smell of hot bread while your stuck in a cabin while its raining all day is next to heavenly.

I appreciate honest opinions, so please don't hold anything back.
I learned a long time ago that a man that thinks he's got it all figured out about anything, has no room to learn anything. So keep the opinions coming.

Thanks

Scott

[Sunset]

Charlie I used your removable sink idea you mentioned on the B&B forum years ago and loved it on my Belhaven. Also you mentioned a clay pot on the stove for heat, that worked great also on my Belhaven. My brother uses the clay pot on his Coronado 25 also.

Rorik I have always liked the Cape dory boats.

[Captain Smollett]

get as far as way from the pop-up camper way of thinking as possable. My wife puts up with a lot of stuff from me but if she's not somewhat comfortable I end up being the one not so happy somehow.

I understand, and that's kind of my point.  It's not THAT uncomfortable...just different.

We've talked here before about the reduction of misery principle....finding those areas where YOU feel you need to 'add comfort' to make things not only bearable, but enjoyable.  If that means for you to have a shower, an oven, six sinks, well...your boat!

But, here's the danger that I have seen numerous times.  It's all about expectations and not meeting them.

Living on a boat is different.  It's different in many ways that are VERY subtle and hard to put into words.  If a person goes into this adventure with the mindset that the boat has all the 'comforts of home,' meaning not the comforts themselves but rather the IMPLEMENTATION of those comforts as they would be in a house, they are almost sure to be disappointed.

Unless you are on a very large boat...which is why you see a LOT of couples cruising on 45 footer and bigger.

Once you decide to "go small," it takes some re-thinking.  Because without that, it is an endless cycle of disappointment that leads to "if only the boat were bigger, we'd have room for X."  X gets added, then there's another thing, and these things are always some permutation of "like at home."

Living or cruising on a smaller boat requires a different set of compromises...not in what comforts are accepted, but in HOW they are implemented.

It does not have to be "pop up camper," but there may be an element of that I suppose.  But it will almost certainly NOT be "home."  If that is what your wife is expecting, on a psychological level, she is probably on a path of disappointment.

Its funny I am the one that wants the gimbled stove with oven. I love to bake all kinds of bread. The smell of hot bread while your stuck in a cabin while its raining all day is next to heavenly.

Bread baked in the pressure cooker is good.

The pressure cooker has other advantages:

It cooks faster (I've baked bread in 25 minutes of cooking time in the p-cooker), so it (a) uses less fuel and (b) heats the cabin up less.  The latter might help eliminate the "need" for Air Con in the summer. 

See how these things get built on each other?  "Systems" in the house, or even in a camper to some degree, don't have to be engineered like this.  There is "infinite" fuel, plenty of space to add additional 'support systems,' etc.  Putting "stuff" into a house has almost none of the drawbacks of attempting the same thing a small boat.

The boat is not a house!   ;D

You don't have to worry carrying it with you, where/how to store it and where/how to resupply.  This applies to electricity, fuel, water and food.  An oven or a shower may not in themselves be that big of a deal, but they both equate with (a) increased complexity and (b) increases in other areas that multiply VERY quickly. 

For example, an oven uses more fuel than the p-cooker to cook the same loaf of bread.  The end product is the same, so there is no 'quality' lost by one method over the other.    But, with more fuel means bigger propane bottles (or whatever fuel you use) and/or more resupply stops.  It also means less available space for other things...things that may be considered comfort-providing luxuries.

On this latter point...one way to put an oven in our Alberg 30, perhaps the simplest way, would require giving up the space where we keep the laptop in port for such things as watching DVD's.  A solution could be found, but my point is adding an oven creates OTHER problems elsewhere.  At least perhaps it does...no absolutes.   ;)

Finally, please take a look at this post that I made at the end of our first year of living aboard (mostly marina time).

Punchline:

Living aboard is not much different from living anywhere else.  The local environment is different, perhaps, but the issues are not.  The attitude wins the day.

Don't sweat living aboard.  The loss of convenience (we have no oven, no fridge, no tv, no pressurized running water or shower) is completely insignificant.  The spiritual gains, the connection to weather,  neighbors (other liveaboards and transients), the knowing "I CAN" so far outweigh the perceived conveniences that no comparison is really justified that one merely face those fears to conquer them.

On that note, I highly recommend the book Changing Course by Debra Cantrell for anyone looking to go cruising with a spouse or partner.  Some very good stuff about fear in that book.

Fagor even has a cookbook - "Tastefully Under Pressure" - www.fagoramerica.com.

I'll second that...that cookbook has some incredibly tasty recipes!  Here's an example   ;D

[rorik]

Sunset: Thanks, me too.
The only downside I see to your brothers idea, is the space for a sump for the grey water. And a pump to get it out of the boat.
Food can take up a lot of room. Especially if you start adding extras, like adult beverages. Or that special flour for that special loaf.  ;D
I downsized from a house to an apartment, then to a boat and shoreside storage and finally to just a boat.
It gets easier at every step.
I've had friends, well, ex-friends, accuse me of "living out of a bag", being "one step up from living on the street" when I moved aboard.
The thought it was like a camper. Or worse.
They don't see what you, or many of us here see: that life on a boat is full of those "hot bread while it's raining outside" moments.
Something I never found in a house. And one of the reasons I'll never try to make my boat like a house.

[Sunset]

I agree with the KISS concept and I will over time probably change some of the expections, it will be slow going to change my wife's.

There simply has never in my life been the feeling I got from living on my little Belhaven a few weeks at a time with few comforts. I felt free and at peace when I was on her, whether at anchor, at the marina or fighting bad weather. I know that's were I belong.

When my brother sold his business, his new house and most everything else to go cruising he told me it was the most liberating thing he has ever done. He said he findly has the peace he's been looking for. Only a boat to care for.

[Captain Smollett]

Hi Scott, Grog for both you and your brother.  And your wife.   ;)

I dug out this old link.  It's pretty much a rehash of what's been said before in the thread, but it has the pictures of the end product.

Oven shmoven...   ;D ;D ;D

[Godot]

Must haves.  I have been thinking of must haves for the next, currently theoretical, boat. My personal needs are pretty simple, and are based on ONE person living aboard, with the occasional guest(s).

1) Must have: A comfortable place to sit and sleep (under the conditions I'm using the boat), not in the forepeak.
1a) Nice to have: an additional double bunk, either convertible or permanent. For those times a particular guest desires to get cozy.

2) Must have: Enough storage for food, clothing, gear for the time expected away (or at least between resupply stops).
2a) Nice to have: Enough storage for my other hobbies, should the opportunity present itself to do them (hiking/backpacking, SCUBA, etc...)

3) Must have: A galley with stove, sink, and pots/pan storage.
3a) Nice to have: A galley with four burners, oven, microwave, double sink, dishwasher, refrigerator, garbage disposal, and private chef.

4) Must have: a place to do "business"
4a) Nice to have: an enclosed head with enough room to squeeze in without feeling claustrophobic, but tight enough not to get thrown around too bad.

5) Must have: Some place to store wet gear
5a) Nice to have: a place to store wet gear near the companionway so as to not get everything soaked inside (an aft located enclosed head would be perfect here).

If I were to buy a new boat today, clearly the Must Haves are must haves. Of the Nice to Haves I would probably prioritize 4a (I'm a bit shy), 1a (but like company), 2a (and hobbies), 5a (but hate a wet cabin).  I probably wouldn't bother changing boats without getting at least a couple of these (probably...there are a couple scenarios that might change my mind...). 3a is clearly a fantasy as I don't have all that in my current house (missing dishwasher and disposal, although oddly enough I do currently, if temporarily, have the private chef).

[rorik]

The head on my CD28 is enclosed, although it's not aft. Originally, the head was on the port side with a vanity, small sink and upper cabinet opposite. There also used to be a 20+ gallon holding tank in the forepeak under the berths.
Now, the head is still in the same location, but it's a Lavac, so a lot of extra plumbing went away. The holding tank, still under the v-berth, is now only 10 gallons.
The sink and vanity were removed, and that space now holds all my jackets and foulies along with harness, PFD,   gloves, hats.
What I gained is storage under the v-berth that will hold 100 lbs ("water" weighs about 8lbs/gln) without upsetting boat trim and a wet locker, that while I will get the sole wet going from companionway to under the mast, will drain into a sump in the sole between the Lavac and the locker.
Also under the v-berth, there used to be drawers. The drawer fronts are still there, but glued in place. By removing the actual drawer and building a shelf at the same level as the drawer bottoms that I can access from above by way of a lift out lid, I quadrupled the available space on each side of the forepeak.
Drawers are nice. Dedicated sinks are nice. But what a small boat really needs is storage.
Which, obviously, is one of my "must haves".

[Sunset]

There is something else I haven't put much thought into yet and haven't talked to the designer about, that's tanks sizes and placement.
All of that is going to use valuable cabin and storage space. Not counting a nice house battery bank.
A 30gal fuel tank should give me a motoring range of 400-450 miles. If the information I get on the beta20 is close, 1/2 gal hour pushing the boat at near hull speed.

The water tank, I was hoping for about 30 on it also and 20 on the holding tank.

The weight of the water and fuel topped off along with 4 group 31 agms is going to be around 700 lbs. I think I'll let Graham tell me where these should go and build around them. The last thing I want to do is launch the boat and find the bow sticking out of the water.

I saw a video on youtube that Lat& ADD did on the Dana 24. Its amazing what Pacific seacraft got in a 24 footer.
I am assuming that I could get that much in a custom 28. I like the openest of that little boat.

[Captain Smollett]

Also under the v-berth, there used to be drawers. The drawer fronts are still there, but glued in place. By removing the actual drawer and building a shelf at the same level as the drawer bottoms that I can access from above by way of a lift out lid, I quadrupled the available space on each side of the forepeak.
Drawers are nice. ... But what a small boat really needs is storage.

Wow, that is really interesting, because I am doing the same to all the drawers in the Alberg 30.  The drawers waste a TON of available space.

[rorik]

There is something else I haven't put much thought into yet and haven't talked to the designer about, that's tanks sizes and placement.
All of that is going to use valuable cabin and storage space. Not counting a nice house battery bank.
A 30gal fuel tank should give me a motoring range of 400-450 miles. If the information I get on the beta20 is close, 1/2 gal hour pushing the boat at near hull speed.

The water tank, I was hoping for about 30 on it also and 20 on the holding tank.

The weight of the water and fuel topped off along with 4 group 31 agms is going to be around 700 lbs. I think I'll let Graham tell me where these should go and build around them. The last thing I want to do is launch the boat and find the bow sticking out of the water.

I saw a video on youtube that Lat& ADD did on the Dana 24. Its amazing what Pacific seacraft got in a 24 footer.
I am assuming that I could get that much in a custom 28. I like the openest of that little boat.

If you're building a 28' boat, it will most likely be lighter than my poor, fat Mathilda. It's not really her fault, I just still have a lot of stuff. Anyway, a 1979 Cape Dory 28 is supposed to displace 9000lbs. When I hauled last February, the travel lift said..... 11,500lbs.
I re powered last fall/winter. I installed a Nanni N2.14.
Kubota block marinized by Nanni in France. They provide the OEM install to Beneteau, Jeanneau, Morris and others....http://www.nannidiesel.com/index.php?option=com_content&view=article&id=94&Itemid=5&lang=en

The Nanni is 2 cylinder, 13 horse and with a prop change, it pushes poor fat Mathilda at hull speed. We can actually go fast enough to create a pressure wave large enough to push water up the rudder tube into the cockpit....  ;D I had to change props because 30 odd years ago, Volvo transmissions spun the other direction so I had a left handed prop. Now it's right handed.
If I had a 20 hp engine, I would be over powered. The smaller engine also saves on fuel. I use a little more than a liter an hour which, very roughly, means I can run for 45 - 50 hours on 13 gallons.
I have a 13 gallon fuel tank and 2 five gallon jerrys. The jerrys are secured in the lazarette. Weight down low, no windage, if it spills it's in the bilge - not on the deck. And I have 2 jerrys to balance my load if I have to drag fuel in by hand.
Take the extra money you'd spend on the bigger engine and buy a code zero sail. Mine came from North, but any sailmaker can build one.
http://www.na.northsails.com/SAILS/DownwindSails/CodeZeroA0AsymmetricSpinnakers/tabid/23618/Default.aspx
I can manage 2 -3 knots in 5- 8 knots of wind.... motor??....pfffffttt.... it's a sailboat!  ;D