Heat Your Wood Fired Hot Tub in 2-4 Hours

Heat Your Wood Fired Hot Tub in 2-4 Hours

How long does it take to heat an AlumiTub?

That's one of the most frequently asked questions we receive from people wanting to know how much time they should expect to spend heating their wood burning hot tub. While initial heat time will vary depending on the temperature outside and that of the water you're filling your hot tub with, the simple answer is that it should take 2-4 hours. Standard hot tubbing temperature is 102-104 degrees, but the beauty of a wood fired hot tub is that you can make it whatever temperature you want by adding more or less firewood. Getting the water just the way you like it can be an art that you'll get the hang of after a few uses. Once it reaches the temperature you want to soak in, an AlumiTub will hold its heat for days at a time with just an armful of wood a day. The same can't be said about all wood fired hot tubs. 

Wooden hot tubs without a lining lose heat when the wall and base of the tub are wet, allowing for heat to pass through. Unlike traditional cedar hot tubs, AlumiTubs marine grade aluminum lining is triple insulated with thermal properties around the tub, at the base, and on top of the water, helping to retain heat where it would otherwise be lost. AlumiTubs are also designed with an internally submerged firebox, which is more energy efficient than its externally located firebox counterparts. Using convection, an internally located firebox expedites the heat time by using convection to directly heat the water. 

AlumiTubs wood burning hot tub design is made for all season use, even in temperatures as low as -50 degrees. To help you use less firewood and save time tending to your hot tub, here are a few tips that can help you heat it more efficiently, even in the coldest Canadian winter climates.

  1. Place rigid insulation at the base of your tub. You can hide the insulation by wrapping our Stainless Steel Bottom Band around your AlumiTub. Many of our customers do this to expedite the initial heat time and share that it reduces their heat time by an hour or more.
  2. Place the provided insulation beneath your hot tub lid to trap in heat from the waters surface while it heats, and put them back on between uses. You'll find that by doing so, your AlumiTub will drop just a few degrees overnight. Add a log to the fire before your morning coffee and you'll be ready to hop back in before breakfast. 
  3. Wrap your AlumiTub in the reflectix insulation provided with your order, sandwiching it between the tub and the cedar cladding. This helps retain heat for much longer.
  4. Use only dry firewood, opting for high quality wood for an optimal burn. There's no perfect recipe for how to build a fire, but with a little technique and the right materials, you can significantly improve your hot tubs heating capacity. Wet firewood will cause smoke and poor heating, so make a dry spot to stack your wood and keep it as dry as possible between uses. 
  5. Using a paddle or a piece of wood that's roughly 4ft long, stir the water from the bottom of the hot tub to evenly distribute the heat. This not only ensures all of your company has the same temperature water at their feet as they do at their shoulders, but it will help circulate the heat throughout the water, making it hot in a hurry.

How to heat your wood fired hot tub

To build the fire, start by placing a few pieces of kindling in the firebox that are anywhere from 1-4 inches in diameter. Allow air intake by placing the stove lid on the firebox just partially, using it as a damper. As the fire builds, add larger pieces of wood as your would in a regular wood stove. Check the thermometer. Once it reads 90 degrees, stop adding wood and allow the temperature to rise to 104 on its own. If you continue adding wood, the water will get too hot to soak in and you'll need to cool it off with cold water from a garden hose.

If heating your hot tub in record time is of paramount importance to you, you can also install a secondary or alternative fuel, like propane, natural gas, electricity or even solar. This can help reduce the initial heat time to just over an hour in our Standard size tub and is particularly useful for owners who want to make their AlumiTub compatible with residential use, or Airbnb hosts looking to keep their wood burning hot tub at the right temperature for their guests arrival. Dual heating also allows you to take off for an afternoon of snowmobiling, skiing, fishing, hiking or take a much needed nap without having to tend to the fire. It offers a balanced experience where you're only heating the tub when you need it, while still having the option to heat it by wood or by an assisted fuel source. Flexibility is nice to have, especially as your needs may evolve over the decades you'll have your AlumiTub. To make your wood burning hot tub compatible with a secondary heat source, contact us to request this customization at the time of placing your order.

While this post provides tips to speed up your tubs heat time, speed isn't the name of the game with a wood fired hot tub. In fact, the whole concept is that it allows us to develop a ritual of chopping the wood, filling the tub with a natural water source, stoking the fire and allowing us a moment to disconnect from the hustle and bustle before soaking in the fruits of our labour. Think fast food vs. your best home cooked meal. There's a time and a place for speed, but there's also good reason to take our time where it matters, and a wood fired hot tub offers a natural experience that stands in stark contrast with electric spas. Just like your french pressed Sunday morning coffee, there's something sweeter about the taste than an instant coffee that's ready with the touch of a button. The ritual allows us to pour a little more love into it, and the reward is that much sweeter. So take the opportunity to enjoy a slow down. Listen to the fire crackle as you stoke the flames and bring your water up to your desired temperature. Chop some wood for later, make dinner and pour yourself a drink, and your wood burning hot tub will be ready to warm your tired toes within a few hours time. 

To learn more, check out our Ultimate Guide to Wood Burning Hot Tubs. Or to see how AlumiTubs work, visit our videos page where you'll find tutorials on how to heat your wood fired hot tub.