Wood-fired hot tubs offer a natural and authentic bathing experience, free from electrical components and modern complexity. These tubs use a simple yet effective principle of natural water circulation and heat transfer, making them both eco-friendly and relaxing.
Understanding How the Stove Works
A wood-fired hot tub uses a stove that heats the water through convection. The fire in the stove heats up the metal walls, which in turn warms the water flowing around them. The water circulates naturally — no pump is needed. Cold water enters the stove from the bottom and, as it warms up, it rises back into the tub, creating a continuous flow.
Types of Wood-Fired Hot Tubs
There are two main designs:
- Internal stove: The heater sits inside the tub, directly heating the surrounding water. It is simple and efficient but slightly reduces bathing space.
- External stove: The heater is placed outside the tub, connected via pipes. This setup saves space inside the tub and is easier to clean and maintain.
Heating Time and Efficiency
Typically, it takes around 2–3 hours to heat the water, depending on volume, outside temperature, and the strength of the fire. Hardwood logs like oak or birch burn longer and hotter, improving efficiency. Once the desired temperature is reached, adding a lid helps retain the heat longer. For more details, check our article about electric heaters and hybrid systems.
Maintenance and Water Care
To keep your hot tub in good condition, regular maintenance is essential. Proper water care ensures safe and pleasant use, while checking for leaks and sealing small cracks helps prolong the life of the wood. Always drain and clean the tub before long periods of non-use.
Preparing for Winter
During freezing months, it’s crucial to empty all water from the tub and pipes to prevent damage. If you plan to use it in winter, maintain a steady fire and ensure proper insulation. You can find more about filling and emptying your hot tub safely in our guide.
Choosing the Right Wood
The choice of material greatly affects durability and insulation. Learn more about the best wood for outdoor hot tubs — such as larch, spruce, or thermo-wood — to find the perfect balance between quality and cost.
Building a Sunken Hot Tub
If you’re considering a more permanent installation, check our guide to sunken hot tubs for inspiration and practical advice on building one that integrates seamlessly into your garden.
Conclusion
Wood-fired hot tubs combine simplicity, sustainability, and relaxation. Whether you prefer an internal or external stove, understanding how your system works helps you get the most out of your investment and enjoy countless relaxing evenings under the stars.