Everything Happens Inside the Tub.
The stove stands in the water with you, behind a timber guard, instead of sitting outside on its own footprint. There is nothing to plumb, no hoses running across the ground and no second patch of space to find room for.
Cedar staves, stainless steel straps, an insulated cover and a set of steps arrive as a kit. The floor, the benchtops, the stairs and the heater guard come already made up, so most of the work is standing the staves and pulling the straps tight.


Key Features
The Heater Stands In the Water
The firebox sits inside the tub and heats the water it is standing in. There are no hoses, no external pipe run and nothing lost between a stove and the shell, so the water comes up faster than it does on the same tub with the heater outside it.
It is built from 2 mm stainless steel sheet, which gives it a heavier body and a longer working life than the thinner stoves it replaced. A heat shielded flue carries the smoke clear of the tub.

Western Red Cedar, or Thermowood
Cedar is the standard. The staves are around 38 mm thick, and the grain swells evenly once wet, which is what pulls a barrel tub water tight without sealant. It also carries its own scent and resists rot and insects on its own.
Thermowood is the alternative, hemlock baked at 180 to 230 degrees for up to 96 hours. The heat drives out what fungi feed on, so it holds its shape, insulates a little better and lasts longer outdoors.

It Fits Where an External Heater Will Not
Nothing stands outside the shell, so the tub needs only the ground it sits on. That counts on a small deck, in a courtyard, or anywhere a run of hose to an external stove would be in the way.
It also opens up installs an external heater rules out. With no stove to reach around the side, the tub can be recessed into a deck or set into the ground.

Covered Between Soaks
The cover is a high density polystyrene foam core in UV resistant marine grade vinyl, with chlorine resistant fittings and lockable safety clips.
Left on, it holds the heat in after the fire dies down and keeps leaves, rain and anything else out of the water.

At a Glance
- Capacity: 2 to 8 people depending on size
- Diameters: 1500 mm, 1800 mm and 2100 mm
- Depths: 900 mm or 1200 mm
- Timber: Western Red Cedar, or thermo treated hemlock
- Heater: Internal wood fired, 2 mm stainless steel
- Heat up time: 1 to 3.5 hours from cold to 38 degrees
- Power needed: None
- Delivery: Pick up, Tasmania, or interstate freight

Why an Internal Heater
An internal stove asks less of the space around it. There is no separate footprint for a firebox, no hose run to step over and nothing outside the shell that has to be reached around, which is what makes a recessed or in ground install possible at all.
It heats faster too. The firebox sits in the water rather than being plumbed to it, so none of the heat is lost on the way.

NO RUNNING COSTS
Firewood heats it. Nothing is drawing power between soaks.
A SMALLER FOOTPRINT
The tub needs only the ground it stands on. No space set aside for a stove.
FASTER TO HEAT
The firebox sits in the water, so none of the heat is lost on the way.
NOTHING ON SHOW
No hoses and no pipe run. Just the tub and a flue.
Specifications
| Diameters | 1500 mm, 1800 mm, 2100 mm |
| Depths | 900 mm or 1200 mm |
| Capacity | 1500 mm seats 2 to 3, 1800 mm seats 4 to 5, 2100 mm seats 6 to 8 |
| Timber | Canadian Western Red Cedar, or thermo treated hemlock |
| Stave thickness | Approximately 38 mm |
| Water capacity | 1300 to 4500 litres depending on size |
| Straps and fittings | 304 stainless steel |
| Heater | Internal wood fired, stands inside the tub |
| Heater material | 2 mm stainless steel |
| Heat up time | 1 to 3.5 hours, cold water to 38 degrees |
| Flue | Heat shielded, supplied with a cleaning kit |
| Heater guard | Timber separation fence, preassembled |
| Electricity | Not required |
| Cover | High density foam core, marine grade vinyl, lockable clips |
Included and Delivery
What’s Included
- Wooden floor base plate
- Wooden staves
- Heater separation fence
- Wood fired internal heater with flue and cleaning kit
- High density polystyrene foam thermal insulation cover
- Benchtops
- Wooden stairs
- Assembly manuals, instructions and installation video
- Hot tub liner
Includes a hot tub liner. Timber tubs depend on a precise fit between the staves to stay watertight, and once assembled and sealed correctly, yours will hold water on its own. The liner is included so you always have a simple way to guarantee a flawless seal. Fit it at any time, with no additional sealing or maintenance required.
Delivery and Installation
- Pick up from the warehouse at no additional cost
- Delivery within Tasmania for an additional $300 to $500
- Interstate freight from $500 to $1500
Freight varies with size and destination. Contact us for a figure on your address before you order.
Light It, and the Rest Takes Care of Itself
Fill it, stack the firebox and let it come up while the afternoon goes. There is no power bill behind it and nothing outside the tub to work around. Just hot water, cedar and woodsmoke.



















Anna –
Beautiful tub! Exceptional quality wood! Loving it and wish we bought it earlier!
Damien –
The hot tub has been a fantastic addition to our mountain cabin and I thoroughly recommend Shym Spa’s
Fiona Bulman –
Great service and follow up. Our hot tub was exactly what we hoped it would be. Looks fantastic, easy to heat with the firebox. Hubby most impressed with comprehensive installation instructions both written and video. Highly recommend these guys.
Chinatsu –
We bought a hot tub with internal wood fire from Shym Saunas, partly because we want to support local businesses, but also because of their expertise and competitive pricing. Art was very attentive with our queries during assembly and the guide and video provided were very helpful. As the wood fire component is in the water, it works quite efficiently and water gets very hot. Overall, we are very happy with the product and service.