Houseboats are known for spending lots of time anchored or docked. But can any houseboats move around under their own power?
The vast majority of houseboats have motors of some kind. Houseboats, or cruising houseboats, have either outboard or inboard engines for moving around, along with a generating engine for producing electricity.
In this article, we’ll go over everything you need to know about houseboat motors. This includes the difference between engines and motors, houseboat motor types, fuels, and how to choose the best propulsion system for your next houseboat. We’ll also cover emerging electric houseboats.
We sourced the information used in this article from trusted marine design guides, houseboat experts, and houseboat manufacturing companies.
Are Engines and Motors the Same Thing?
Actually, no—motors and engines are not technically the same. However, people have used them interchangeably for decades, and we’ll consider them the same thing in this article.
A motor is technically defined as a machine (generally powered by electricity) that converts one form of energy into rotary mechanical energy.
An engine consumes fuel (like gasoline or diesel) or the direct product of a fuel (like steam from a coal-burning boiler) and converts it into mechanical energy.
When people ask if houseboats have motors, they generally want to know if houseboats have engines and can propel themselves. This is the question we’ll address in this article.
Houseboats Without Motors
Some houseboats never came with motors and will never operate under their own power. These are not the majority of houseboats, but they make up a notable segment of the total houseboat numbers. We refer to these as ‘stationary’ or ‘permanent’ houseboats.
Stationary houseboats are usually just houses built on floating foundations. Their materials and construction methods closely mimic traditional houses, with one key exception—they’re built on top of a steel barge or pontoons.
These types of houseboats are usually custom-made by their owners, and they were once common in many parts of the country. The most notable examples of stationary houseboats were used on the Mississippi River during and around the time of the Great Depression. These were known colloquially as ‘shanty boats.’
Today, most of the original shanty boats are gone. Stationary houseboats can be found in canals and rivers in small neighborhoods, usually occupied entirely by vessels of this type. These houseboats can be found in many parts of the country, such as the southern and central marsh areas of San Francisco Bay.
Houseboats With Motors
The majority of houseboats come with engines of some kind. These are also called cruising houseboats, as they’re designed to move along under their own power in both forward and reverse. Cruising houseboats are the most numerous for both rental and living aboard. Cruising houseboats are found most often in rivers, lakes, and other protected waterways.
Generating Engines vs. Propulsion Engines
There are two primary kinds of engines (or motors) found aboard houseboats. The first and most common is a propulsion engine, which rotates a shaft and a propeller. Propulsion engines allow the boat to move under its own power, both forward and in reverse.
Generating engines, or generators, serve an entirely different purpose. These engines are generally more efficient and quieter than propulsion engines, and they consume much less fuel.
The primary purpose of generating engines is to produce electricity to charge a houseboat’s battery bank and to run appliances. Generating engines run quietly and are designed to run at constant speeds for sustained periods.
Houseboat Motor Fuel Types
Gasoline and diesel are by far the most common fuels used by all types of houseboat motors. Usually, the generator and propulsion engine aboard a houseboat run on the same fuel, and there’s typically a single fuel tank (or system of connected fuel tanks) that runs both.
This simplifies the fueling process and provides a reliable source of fuel for all power plants aboard the vessel. Other types of engines found on other boats (such as coal or heavy fuel oil-fired steam plants) are never found aboard houseboats due to their excessive size, weight, and complexity.
Gasoline is the most common fuel source for small houseboats, as gasoline engines are much lighter and simpler than diesel engines. Diesel engines are found on larger houseboats, as they’re more powerful for their size and much more fuel-efficient.
Outboard Houseboat Motors
Outboard motors are low-maintenance and extremely common on houseboats. Outboard motors are self-contained propulsion units. They are usually powered by gasoline and mounted partially above and partially below the waterline at the back of the boat.
Outboard motors come in many shapes and sizes with various power outputs. Houseboats almost always use at least one outboard motor with at least 50 horsepower, though 150 to 300 horsepower models are most common.
Sometimes, houseboats have more than one outboard motor, though they never have more than four. Outboard motors are linked directly to the steering system of the boat, and the motor itself turns to direct the propeller instead of using a rudder.
The advantages of outboard motors are numerous up to a certain size where they become impractical. Outboard motors turn the whole propeller, which provides superior maneuverability—especially in reverse.
Outboard motors are also easier to maintain, as you can remove the motor for maintenance with ease. Additionally, outboard motors expose the entire engine when the cover is removed, which means there’s no cramped engine compartment to squeeze into.
The downside of outboard motors is their size and weight. There’s only so much weight you can add directly to the back of a houseboat, so larger vessels require center-mounted inboard motors instead. Additionally, outboard motors are rarely diesel-powered, which limits their efficiency.
Houseboats that use outboard motors as their primary propulsion hardly ever have an additional inboard propulsion motor but almost always have a separate generator. Sometimes, houseboats with inboard motors have a small outboard for backup and maneuvering.
Inboard Houseboat Motors
Inboard houseboat motors are quite common and found on both small and large houseboats—but mostly large vessels. Inboard motors are installed in the center of the boat, usually deep in the floor or in a separate compartment.
Inboard motors offer a lot more fuel efficiency, especially when they’re diesel-powered. Additionally, inboard motors are more durable, robust, and longer-lasting than outboard motors. An inboard motor can also function as a generator for the vessel and run in neutral while charging the batteries.
Inboard motors vary widely, especially on houseboats. And they can be surprisingly small for the amount of boat that they push through the water. Most houseboats have gas or diesel-powered inboard motors ranging in size from four inline cylinders to twelve cylinders in a V-configuration.
Inboard motors do have a few notable downsides. For one, maintenance is more challenging due to the confined spaces they reside in. Additionally, carbon monoxide is a threat as the engine is almost always housed somewhere under the floor in the cabin.
Inboard motors are also more expensive to maintain, which can be a major headache in the event of flooding or fuel contamination. Additionally, they make the cabin louder unless they’re excessively baffled. Also, inboard motors contribute to that well-known oily ‘boat’ smell.
But despite their shortcomings, inboard motors are still preferred by most cruising houseboat owners due to their high efficiency, seamless operation, power, and durability. These engines last many thousands of hours before needing a major overhaul—especially if they’re diesel-powered.
Houseboat Motor Range and Efficiency
Houseboat motor ranges and efficiency vary based on the size and efficiency of the motor and the size of the boat. Most houseboats can travel about 50 or 100 miles without refueling. That’s considering that the average fuel efficiency of a houseboat is about 1/2 to 1 gallon per mile.
Depending on the size and location of the vessel, houseboats can have a fuel capacity anywhere from 50 to 200 gallons. Much of this fuel will be used for propulsion, though a sizable amount is usually kept in reserve by the owner for running the generator, heater, or other fuel-burning appliances.
Houseboat Motor Speeds
Houseboat engines can propel the average vessel at speeds ranging from 5 to 10 miles per hour or about 4 to 8 knots. There’s very little variation in this, as houseboats are limited by their hull shapes.
Some vessels with similar power plants do something called planing, which greatly increases their speed. Planing isn’t possible on most houseboats, as they’re too long and heavy to rise out of the water. The power required to plane a houseboat would rip the transom right off the hull.
Are There Electric Houseboats?
Up until recently, no—but that’s beginning to change. Over the last decade, companies and builders have begun experimenting with electric propulsion systems for houseboats. There are also diesel-electric and gasoline-electric hybrid systems that have seen limited use. Houseboats powered by electricity use actual motors, not engines.
These are not the wimpy battery-powered trolling motors found on fishing boats. Companies like Elco Motor Yachts produce high-powered electric power plants for houseboats that exceed 100 horsepower and have a range similar to standard diesel-powered vessels.
The future of electric houseboats is still to be seen, but there are a few examples floating around in American waters. Many of these are custom builds, though some production houseboats have been retrofitted with electric inboard propulsion.
As it stands, conventional inboard and outboard houseboats are still the most numerous by far.
