How to Heat a Sailboat: 6 Practical Options

For most sailors, boating season ends when the weather begins to get cold. It’s just too unbearable being out on the water with such a strong chill in the air. Or is it? If you could heat up your boat, you could extend the sailing season even longer, which would be delightful. How do you warm a sailboat?

We recommend the following 6 options for heating your sailboat:

  • Sail south
  • Fully insulate you sailboat
  • Use a forced-air furnace
  • Try a reverse cycle air conditioner 
  • Get some electric heaters
  • Rely on hydronic heat
  • Warm up with a heating stove

If you have yet to hear about some of these heating options, keep reading. In this article, we’ll discuss each heating method in-depth, including some practical tips you can use for safe, efficient heating aboard your sailboat!

Stay Warm on Your Sailboat with These 6 Methods

Southernly Sailing

This first option for keeping toasty aboard your sailboat doesn’t require any heating units. Instead, when you feel those wintry winds chill you to the bone, set course for the south. In the United States, southern states tend to stay pretty warm all year long, even when most of the rest of the country is suffering from bitterly cold winters.

You can reliably sail to Florida, California, or anywhere in the southern part of the country and feel instantly warmer. Try it for yourself! 

If you don’t have the luxury to spend your winter in warmer locations then here are a few ways to stay warm during cold weather.

Fully insulate your sailboat

Insulating your boat will not only allow you to retain the heat in the cabin but it will also minimize the humidity levels
and condensation in the cupboards. By insulating your boat you will have no condensation issue in your cupboards and cabinets besides the heat retention will greatly improve.

Having low humidity and condensation levels will make it a lot easier to heat up your boat. In addition to that carpeting your boat is also going to provide good insulation during the winter months. I would recommend laying out a carpet and a carpet underlay underneath the carpet to insulate your floor properly. This technique alone, will make a huge difference in the temperature of your cabin.

When selecting your underlay, make sure you select the one which has the highest insulating properties, generally the underlay that is designed for concrete or cement slabs provides the highest insulating properties and a good option to go for. Check out this useful video on how to insulate your boat:

Forced-Air Furnace

A forced-air furnace is another great option to consider. This heating system uses propane, oil, fuel, or gas as a main heat source. Return ducts allow the forced-air furnace to absorb outdoor air, warm it up, and then send it back to you so you can fight the cold. 

All the excess exhaust should go off-deck if your furnace is ducted correctly. Using a forced-air furnace to its fullest extent will require the installation of ductwork in your sailboat. This can be costly, but if you plan on sailing in cooler weather in the years ahead, then it’s a worthwhile investment. 

The main drawback with this system is finding a proper place (close enough to the cabin) to install the furnace. Forced air furnaces are by large installed in the stern locker, located 10-15 feet away from your cabin. Blowing the heat through the ducts this far will cause heat loss. To prevent the loss, you need to insulate your pipes using armaflex insulation material. Here are some advantages and disadvantages of forced air furnaces. 


  • Instant Heat Available Through all cabin rooms
  • The Heating system is easily regulated
  • Solid solution for heat your boat
  • Even heat distributions via the vents
  • Dries air inside the cabin quickly
  • Can easily heat your lockers and the engine lockers


  • It is complex to install the wires and ducts and fuel supply
  • Ducting and isolating the ducts is hard job
  • These furnaces consumes a lot of electricity
  • Carbon build up inside the ducts can cause clogging the ducks in the long run.

Reverse Cycle Air Conditioner

Who says you have to retire your air conditioner when the summer ends? You can keep using it into the fall if yours has reverse cycling. 

A reverse cycle air conditioner can both cool and heat an area, so it’s a great unit to have onboard your sailboat. The refrigeration cycle that normally provides cool air remains intact with a reverse cycle air conditioner, but, when you want warm air instead, that cycle goes backward. 

Here’s how it works. The indoor evaporator coil takes on the role of a condenser coil to make heat. Outside of the unit, your second condenser unit also changes its act, becoming an evaporator now. This allows the second condenser to send cold air out and away from your sailboat rather than keep it in as it usually does. 

Your reverse cycle air conditioner can also work as a dehumidifier and an air purifier, so it’s really like four things in one. Of course, for all that convenience, you will pay significantly more for a reverse cycle air conditioner than most of the other heating options we’ll discuss on this list.

Still, we’d say it’s seriously worth considering buying a reverse cycle air conditioner. You can have reliable cooling on those especially hot days, then sufficient warmth when you’re shivering, and all in one handy unit. Since you’ll want to save space and limit weight capacity on your sailboat, a reverse cycle air conditioner seems like an almost perfect solution. 

Electric Heaters

A few electric heaters on your sailboat can also be a viable option for warding off the cold. Each heating unit within the heater takes electrical energy and transfers it into heat energy that you can feel. That heating unit is known as an electrical resistor.

The electrical resistor includes nichrome wiring to convert electricity into usable heat. Ceramic insulators will also boost the heat output, making electric heaters quite effective. 

You have all sorts of options for electric heaters, many of which are suitable for sailboats. Let’s discuss these options in more detail now.

  • Heat pumps: A compressor within the heat pump uses electricity to kickstart the refrigeration cycle. During that refrigeration cycle, outdoor air passes through the heat pump, with the heat energy separated from the air. That heat then travels through your sailboat, warming it up. Heat pumps also have an evaporator that uses liquid. This liquid will begin boiling so it can be used as a source of heat, although the fluid does not boil at high pressure.
  • Storage heating: Storage heaters are common in the United Kingdom, but they’re used elsewhere in the world too. Clay bricks within the storage heater get warm and then send out the warm air when you need it most. 
  • Fan heaters: A forced convection heater or fan heater includes an electric fan within, hence the name. This fan moves air faster to provide quick warmth. However, you must keep fan heaters away from other items, as they could ignite what’s nearby if it’s flammable.
  • Convection heaters: Thermal conductors within a convection heater will warm up the air when it cycles in. The buoyancy of hot air allows it to rise so cool air can enter the convection heater in greater quantities, being warmed up immediately. Some convection heaters use thermal fluid or oil. They’re less risky than fan heaters, as convection heaters are not as prone to ignition. 
  • Infrared radiant heaters: An infrared radiant heater has elements within that reach high temperatures, releasing infrared radiation. This radiation goes through the heater, connecting with an absorbing surface and becoming heat. The heat is designed to hit items and people rather than the whole space itself, providing optimal warmth. 

Hydronic Heat

We’re still not done discussing heating options for your sailboat yet. Hydronic heat is a type of heating system that’s especially known for its energy efficiency. The internal system has a tube that goes beneath the floor. Usually, this floor is that of a home, but your sailboat’s cabin areas are also applicable. The hydronic heating system then produces radiant heat from the floor up. 

Within your hydronic heat system is hot liquid, typically water. The liquid moves through the heat system’s hoses via piping. All along, the very hot temperature of the liquid is maintained so its levels are near boiling. You can even use your sailboat thermostat to adjust the water temperature in your hydronic heating system through the plumbing manifold.

Depending on how you set your temperature, you can turn on certain zones of your sailboat so those are the only ones that are heated. You can also set different temperatures from one zone to another. If one part of your sailboat stays pretty comfortable, then maybe you set the heat lower than the driver’s seat near the windshield, as this area might get pretty cold. 

The heating unit’s pumps will send in freshwater as needed to be boiled and transferred. As the water eventually cools down, it goes through the boiler again and is reused. That’s a big part of why hydronic heating systems are so efficient. 

Heating Stove

Since you spend so much time on your sailboat, you might as well opt for a heating stove. Also known as a wood-burning stove or diesel drip stoves, not only can these stoves act as a source of warmth, but they can cook food as well. 

A heating stove may rely on diesel fuel or sawdust bricks or other sources of biomass fuel from wood. The stove itself is made of steel, cast iron, or another form of sturdy, durable metal. Within the stove is a firebox with fire bricks around it. Air controls make the heating stove safe to use, as does a ventilating stove pipe that you’d angle offboard, as the combustible gases combine here, which would be dangerous to be around. 

When you light the heating stove, the gases move to the chimney. For the combustion gases to exit the fire chamber through the chimney, your flue gas temperature must surpass the outdoor air temperature. That’s not too hard in the fall! Here are some pros and cons of heating stove:


  • It has Simple design
  • Requires minimum installation
  • Provides Cosy home feeling 
  • It dries the boat well
  • Has a Cooktop
  • It can be used as a source for radiator 
  • water pipes


  • Learning curve
  • Produces soot
  • Chimney installation can be challenging  
  • Takes longer to get the cabin warm

When choosing heating stove for your boat make sure you have a quality carbon-monoxide detector installed and make sure you change the batteries every 6-9 months.

Can You Use Engine Heat to Warm Your Sailboat?

Some sailors also recommend gathering by the engine to take in the heat that’s generated around here. Since your boat engine has coolant fluid that’s warmed up as the engine runs, this warm fluid could send heat towards the cabin. 

This doesn’t make for the most viable heating solution unless you have a heat exchanger, coolant lines, and a fan. The coolant lines should go from your engine to your heat exchanger, which takes the air and warms it up. The fan then sends the cool air towards the cabin. Hoses can push out the warm air to you.

If you like to take your sailboat out somewhere, turn it off, and just sit on the quiet water, engine heat for warmth won’t work. You’re only getting heat when the boat runs. Also, you’re using a lot of fuel for this heating method and potentially putting undue strain on the engine.

So yes, while you can use your engine as a source of heat, it’s not an option we’d highly recommend. 


Has the weather taken a turn for the colder? Don’t retire your sailboat quite yet! With heating stoves, hydronic heat, electric heaters, a forced-air furnace, reverse cycle air conditioning, or even engine heat in rare instances, you can sail well into the colder months while staying nice and warm. 


I am the owner of sailoradvice. I live in Birmingham, UK and love to sail with my wife and three boys throughout the year.

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