DIY: Build Your Own Hot Tub

Build your own wood fired hot tub in a few (relatively) easy steps.

Few home accents say “A skier lives here” more than a hot tub. But these days, when we see hot tubs in ski towns, they’re often attached to McMansions and vacation condos and say “An affluent, second-home owner lives here.” But hot tubs don’t only belong to the elite. Assuming you have a patch of yard to work with, you can build your very own wood fired hot tub. It’s not the easiest job, but if you’re willing to dig a hole and learn some basic concrete skills, you too can be the proud owner of a heated pool. Here’s how to build your own wood fired, in-ground hot tub without shelling out the big bucks. 

DIY Wood-Fired Hot Tub Supplies

  • Shovel
  • Pickax
  • Plastic sheeting (enough to line the interior of hot tub)
  • Roof nails (to tack down plastic sheeting)
  • 2″ closed-cell insulating foam (enough to line interior of hot tub and to create insulating hot tub cover)
  • Chicken wire (enough to line the interior of hot tub)
  • Concrete mix
  • Wheelbarrow
  • Work gloves
  • Concrete sealer
  • Submersible stove
  • Wood fencing (enough to create barrier between stove and main area of hot tub)
  • Quick Drain system

Directions: How to Build A Wood-Fired Hot Tub

  1. Dig your pit. Use a shovel and a pickax to dig a pit, making it at least six inches bigger on all sides than the size of the finished tub you want. Be sure to pick a location free of roots or bedrock. Make the hole as deep as you like, but smaller tubs will heat faster. As for the shape, a keyhole design is ideal, since you can place the wood stove safely away from the larger sitting area. Remember to cut and integrate benches and steps for your tub, too.
  2. Line the pit with plastic sheeting, using roofing nails to tack it into the dirt. 
  3. Add insulating foam to the lining. Cut sections of two-inch-thick closed-cell insulating foam—available at any home-improvement store—and line the pit, laying the foam on top of the plastic sheet. Hold it in place using chicken wire, which should cover the interior of the tub and anything else you want to make out of concrete.
  4. Pour concrete. Get a professional to help you estimate how much concrete you’ll need for the size of your hot tub. Then, mix the concrete in a wheelbarrow, slathering it onto the chicken wire as smoothly as possible. Start high and work low, since drops will fall to the floor of the tub. Be sure to wear gloves during this step. 
  5. Let concrete cure for one week. Once it’s cured, apply at least two coats of concrete sealer. (Note: You’ll need to reseal it every year with concrete paint.)
  6. Buy a submersible stove, such as the Snorkel Stove and place it in the narrow part of the keyhole pit. You’ll want to install wood fencing between the stove area and the soaking area to keep people from accidentally bumping into the burner. Though the stove comes with mounting brackets, it’s best to anchor it with dumbbells to keep it from floating.
  7. Add a drain. The simplest method is to buy a Quick Drain system—a handheld pump that siphons and vacuums out water.
  8. Make an insulating cover out of two-inch closed-cell foam to hold in heat. Fill the tub and stoke the fire at least six hours before your party. The first heating can take closer to 10 hours, depending on the size of the tub. But once the water is warm, it can take as little as six hours to get hot again.

Aaron Huey, the mastermind behind this DIY Hot Tub design, made a giant wood-fired hot tub to host some of the best parties that northern New Mexico has ever seen. They involved numerous DJs and a giant golden bull made of fuel-soaked papier-mâché (which burned gloriously).