Holiday Mansion 450 Coastal
By Jack Hornor
Revised by BoatUS editors in October 2012
FOR SALE: Spacious two bedroom, two bath water front home; 360-degree water views; ideal for entertaining; asking $125,000. Too good to be true, you say? Maybe you should take a look at Holiday Mansion's 450 Coastal Commander houseboat. It could make a great waterfront getaway and, if you find you don't like your neighbors, you can move on a moment's notice.
Holiday Mansion of Salina, KS, was founded in 1965, quickly becoming a leader in the production of cruising houseboats. It's one of the few manufacturers of the era that still exists today. (The company was purchased by Twin Anchors Marine in 2000, Canada's largest houseboat builder.) The 450 Coastal Commander was introduced in 1989 and remained in production until 1997.
The method of construction of the 450 Coastal Commander is still best described as a combination of boatbuilding and mobile home technology. The modified V-shape hull is molded of fiberglass composites much like traditional fiberglass vessels. Balsa core is used in flat areas for stiffness without adding excessive weight. Longitudinal stringers are fir encased in fiberglass, and athwartship bulkheads are construction-grade exterior plywood.
Decks and cabin houses are also a fiberglass composite, and the cabin tops are built with a 1-1/2-inch-thick fiberglass honeycomb-like structure that is extremely strong and light. The deck and hull are joined in a shoebox fashion with sealants and stainless steel sheet-metal screws on approximately 8-inch centers.
The 450 Coastal Commander's construction deviates into the mobile home genre when you examine its interior structure. The most obvious feature is extensive use of inexpensive paneling on nearly all walls, cabin sides and overheads, rather than the hardwoods commonly used on yachts.
Because most of these boats operate in fresh water, Holiday Mansion uses a significant number of the fittings, equipment and hardware that are not particularly well suited to saltwater. While the 450 Coastal Commander may not be built for blue-water cruising, her construction is sound and comparable to the average houseboat.
The foredeck area features three settees along the forward section of the cabin house. Ten adults can be seated in comfort. The side decks are a full 15 inches wide at their narrowest point and allow safe passage from bow to stern. The stern deck area includes the access hatches to the engine room and measures 13 feet, 10 inches from side to side and 6 feet from front to back.
Along the starboard stern deck, stairs lead to the cabin top and an open deck area that measures approximately 12 feet long by 9 feet wide. It's enclosed by a 1-inch diameter stainless rail. Forward of the open deck is the flybridge helm that measures 9 feet across and 6 feet 8 inches front to back with a U-shaped settee along the port side and a pedestal mounted helm seat along the starboard side of the bridge.
By my calculations, this adds up to nearly 400 square feet of usable deck, or one very comfortable porch.
Although the finish and craftsmanship of the 450 Coastal Commander's interior may not rival that of a Trumpy houseboat of the 1930s, it's no less efficient in its use of space for maximum comfort.
Through the companionway at the after end of the deckhouse, you'll see a lounge area to port with a love seat that converts to a berth. To starboard is a hanging locker and head. Further forward is the galley with a U-shaped dinette along the starboard side that converts to a double berth, and to port, a full-size refrigerator-freezer, stove with oven and double stainless steel sink.
Forward and up two steps from the dinette is the main saloon with a full-size convertible couch on the port side and at the forward end is the lower helm with complete instrumentation, engine controls and nearly 360 degrees of unrestricted visibility.
Forward and beneath the main saloon is a second head with shower, two large hanging lockers and a cuddy cabin with port and starboard berths. The headroom in this cabin is limited to 50 inches, so it's a better place for the kids than adults.
Most 450 Coastal Commanders are powered by two auxiliary gasoline engines ranging from 260 to 400 hp depending on options offered over the years. Installations may be inboard with V-drives, shafts, props and rudders or transom-mounted I/O units. Diesel engines were another option, but due to cost they were not popular.
With the 350- to 400-hp engine option, the 450 Coastal Commander is capable of speeds over 30 mph, although a more reasonable cruising speed is in the range of 18 to 22 mph depending on the engines. Although the 450 Coastal Commander has a shallow skeg or keel to aid directional control at slow speed, she is not immune to the handling difficulties common to this type of boat.
As its name would suggest, the 450 Coastal Commander is ideal for coastal cruising, as well as short or extended cruising on bays, lakes and rivers. This would also be a great liveaboard boat. The 450, however, is not well suited to open unprotected water or for making passages through rough inlets. If space and amenities take priority over performance, this could be your affordable waterfront holiday mansion.
Naval architect Jack Hornor was the principal surveyor and designer for Marine Survey & Design, Co., based in Annapolis, MD. He was on the boards of the American Boat and Yacht Council, the National Association of Marine Surveyors, and the Society of Boat and Yacht Designers. He and his wife sailed their Catalina 42, Legacy, based on Maryland's Eastern Shore.