Riverboat series

What is a riverboat, particularly compaired to a houseboat? A riverboat is capable of cruising around semi-protected waters, handling contrary winds, opposing currents, other boat wakes and generally is easier to propel, maneuver and fetch up on a dock or wharf, without the need to break into a sweat over having the reserve power, handling qualities and landing abilities, more commonly seen in houseboats. Most houseboats are grotesquely underpowered, some have no engine at all, living on a dock all their lives, with no hope of ever moving without a tug or push boat. Those that do have engines meander around in cross winds, get shoved every which way in a cantankerous current and parking one at a dock often requires several people fend her off, before she bashes into it hard.
   This riverboat series is intended to address these common set of issues, with typical houseboat designs, which is simply they're not especially efficient, can't handle rough water, don't motor very well (if at all) and wallow around like a floating Winnebago. This doesn't have to be the case and these riverboats are indeed just as the name suggests, capable yachts, that can motor major waterways with much better comfort and efficiency than usually expected. The short of it all is, a riverboat can travel around, in comfort, with all your stuff, friends and enough beer to make the ride enjoyable. If the sea state picks up, you'll be okay and if a current or wind tries to push you around, you can push back and continue on your merry way. Currently one of my larger riverboats (a Floom) is making the "great loop" passage. Starting just south of Chicago, they've come down the Mississippi, hung a left and took the outside passage around Choctawhatchee Bay, eventually getting back into the ICW and crossing the big puddle in the bottom of Florida, to spend the winter with family in Miami. They'll continue up the eastern seaboard in late winter or whenever they get around to it.

   The series starts with Respite and a relatively new addition. It was originally conceived as the smallest practical, while retaining full headroom and the usual accommodations. It became clear initially, that some additional length would help a lot and by respacing the station molds, this boat is easily built in one of 3 different lengths. All the other dimensions remain the same, including the cabin, though this can be changed too. This is a straight "stretch" and a fairly common way to make an existing design longer. Sown below, the 23' version has a shorter cabin and about 1/2 the boat's length is cockpit, so a good fishermen. A longer or shorter cabin is possible if desired, even a raised pilothouse if you want, though admittedly on this small a boat, not the most practical thing you can envision. Both weather decks are self draining and provide high bulwarks for safety and ground tackle handling chores .

   As a weekend retreat, this is hard to beat and her shape insures good efficiency underway. Her waterline length is maximized and she's very stable at rest or powering along. Fuel use at cruising speeds, will be less than a gallon (3 lt) per hour, which is very nice on the wallet. A 20 HP long shaft outboard is all it takes. 

   Her sections show she's a flat bottom, but I've buried the bow a little, so she's not going to slap at anchor or pound underway. This is the easiest hull form to build and it's also the most stable too. The cabin sides can be perfectly vertical, though I don't like this approuch, as it's not as strong and can bash into docks and seawalls if parked next to one and the boat rolls from condisions. I prefer to slant the sides a bit, which is stronger and helps keep the roof line from smashing into stuff, when tied up to a tall sea wall or another boat.

Her general dimensions are:

LOD               20'           (6.09 m)

LWL               19' 3"       (5.86 m)
Beam              7'        (2.13 m)
Draft               9"             (229 mm)
WL beam        6' 4"         (1.92 m)
Disp.               2,855        (1,295 kg)
D/L                 179 
Cp                   .58
Empty hull weight 1,100  (499 kg)
Max speed     8.5 MPH    (13.7 KPH)

Of course her displacement rises with length increases, but not by a bunch, so still easily trailered, launched and recovered at the ramp in the two slightly longer sizes. The three different lengths was to address volume, but also to help those with limited building spaces.

    Plans are currently in the works, but I expect completion by year's end (December 2016). Study plans are $25 (USD) if hard copy and $20 for a uploaded (PDF) version. Hard copy plans are shipped free to any continental US address, while all others will require a shipping quote. Plans are printed on oversize, acid free stock in color. Full plan sets are $160 (USD).


The next size up in this series is Chiusa and she is 26' (7.9 m) on deck. Also a flat bottom design, with similar features as her sisters, having a buried bow and long straight run. Chiusa was the smallest of the riverboat series, but many found this just a bit too big for a backyard build, so Respite was drawn up to address this concern. More information about Chiusa is available in the "Powerboat" section on this site. She has a few options available for her, such as a V bottom if desired, making her more capable in rougher waters and adding additional volume, below the cabin sole. This hull is more accommodating in terms of ride quality, though a little more difficult to build, compared to the flat bottom version. She also has a few different sheer treatments. My personal favorite is the broken raised sheer (first one shown), which helps keep the boat drier in a nasty slosh and can permit more internal volume below decks.

   Chiusa is a taped seam build, though a plank  (plywood) over frame option is possible as well. It's also possible to build her with a regular flat transom, which simplifies the build a bit.

Egress is another design that has more information in the "Powerboats" section on this site. This is a one off, fully planked (plywood) over evenly spaced frames build. She's also a flat bottom and has no additional options, though conversion to a taped seam build is certainly possible. She's 28' (8.5 m) on deck and below the maximum trailerable beam, for over the road transport. When boats get to this size, trailering becomes much more of a chore. Not many ramps will accommodate a boat of this length and maneuvering around a 28' boat, with it's likely 33' (or longer) rig (trailer and boat), isn't for the faint of heart. It will also require a full size truck to drag her around. The idea with trailering this boat is to save winter storage fees. You can launch in the spring, cruise around all summer and haul her out in the fall, just like everyone else, except instead of paying to have the boat stored all winter, you can drag her home and park her in the backyard, where maintenance and repairs can be done, as it's convenient for you.
   As the other riverboats do, her decks are self draining, the bow is buried to prevent pounding and only modest outboard power is necessary, to push her to speed.

Basic dimensions:

LOD     28' 2"                 (8.58 m)
LWL     25' 3"                 (7.7 m)
Beam    7' 6"                   (2.68 m)
Draft      10"                   (254 mm)
Hull weight   2,520 lbs   (1,145 kg)
PPI       715 lbs.              (325 kg)

Her modest beam/length ratio makes her notably more efficient than the smaller riverboats, but she still has plenty of elbow room.
   Study plans are $25 (USD) if hard copy and $20 for a uploaded version (PDF). Hard copy plans are shipped free to any continental US address, while all others will require a shipping quote. Plans are printed on oversize, acid free stock in full color. Full plan sets are $230 (USD).


This 33' (10 m) on deck, V bottom is a good size boat and quite capable as a result, much more so than the smaller riverboats. With Floom, begins the larger of this series and provides more live aboard accommodations, can tolerate full size appliances and hardware, etc. This also means more powder, bigger ground and deck tackle, etc. are required as well. I have to admit trying to talk most novice builders out of plans for this scale of vessel, simply because I don't think most know what they're in for in this regard, without a considerable amount of previous building experence. In addition to Floom at 33' is a 39' (11.9 m) and Belle a 50'  (15.2 m) design. All three of these are big (read huge) projects for the average backyard builder and just outside the probability for a reasonably successful completion. 
   This said, some have, with several Flooms, two of the 39' and 3 of Belle (50') being built. All of the 39' and 50' designs have been professionally constructed, with one finished out by the owner, after the raw hull was completed.

Principle dimensions for Floom are:

LOD         33’ 2”           (10.1 m)
LWL         29’ 6”           (8.99 m)
Draft        10”                (254 mm)
Beam       9’                    (2.7 m)
WLB        8’ 1”              (2.5 m)
Displacement 4,121 lbs. (dry)   (1869 kg)
D/L          71
Prismatic Coefficient     .59
PPI          796 lbs.          (361 kg)
Buttock angle 2.6
Deadrise 42 degrees @ station 1
Deadrise 9 degrees @ station 5
Entry 1/2 angle             20 degrees

Floom has several options, in accommodations, cabin types and sheer treatments. She's very efficient as 33' yachts go and quite comfortable underway too.  


The original Belle has been earning her keep on a local river as a lunch and sunset cruise/excursion boat.  She works about 6 months out of the year and entertains a few dozen guests per outing.

As you can see, this is a big puppy, literally a floating two story home. That's a 9' tender on the aft cabin roof and she can easily carry a 12' dinghy up there and this area is large enough to carry several boats.
Basic dimensions are:

LOD      50'         (15.24 m)
Beam      15' 10" (4.82 m)
LWL      47' 3"   (14.4 m)
WL beam     15' 4"   (4.67 m)
Disp.      41,368 lbs. (18,803 kg)
Cp             .55
D/L              264

As a live aboard, this is a grand ship, but as a passage maker, you'll find she needs a lot of control and power to overcome windage and hull drag. Unlike the other riverboats in the series, this was always intended to remain a "short hopper" rather than a cruiser. She has two steering stations, one in the pilothouse, where the vision around is great and the other is at the forward end of the main cabin.
    Aft of the helm station in the pilothouse is a master suite and egress is down a portside spiral stairway. Access to the roof is available in the aft pilothouse wall or a ladder on the main cabin aft bulkhead in the cockpit. In the main cabin, again another helm station forward with seating to either side. To starboard is a galley with residential size appliances. Directly opposite is a drop leaf table and settee, that converts to a double berth, with storage under. Lots of cabinet space and stowage is possible. Aft of the settee is the entrance to the spiral stairs, tucked into the head's forward wall. The head is directly aft of this, with built in linen closet and a full size bath tub/shower enclosure. Opposite of the head to starboard, is a small cabin with over and under berths. Moving further aft are the two engines rooms, straddling the central passageway to the cockpit companionway. The cockpit is deep and about 10' (3.04 m) long and 14' (4.3 m) wide. Even the foredeck is large, being about the same width and 8' (2.4 m) long. That's a lot of suntan area to enjoy. Her draft is dependant on the propulsion type employed, but it's still not very deep, so you can get in close to just about anywhere you'd like.
    Primary mechanicals, plumbing and electrical are below the main cabin sole. Plenty of tankage for water and fuel are also in the bilge.
    The hull can be plywood, though steel is a recommended option. She's flat bottomed, with a relatively fine entry, but the topsides have a healthy amount of flare to keep her dry and provide more foredeck volume. The flat portion of the bottom planking is held back from the bow and never will pound, regardless of speed she's pushed to.

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