Narvi
Narvi Stony wood-burning sauna stove
Narvi makes the Stony wood stove in 2 versions for saunas of 283 ft³ to 706 ft³. Slide to your room size to see which one fits and how fast it heats.
Updated Oct 18, 2026
Output
not published
Rooms
283 ft³–706 ft³
Stones
463 lb
Sizes
2
Which size fits your sauna?
Your room's effective volume
494 ft³
Best fit: 20
Work out your effective volumeEffective volume = inside volume, plus 1.2 m³ for every m² of glass, tile or stone; × 1.5 for solid log walls (Harvia's rule, used by most planners).
Sizes and specifications
| Model | Output | Room range | Stones | Heat-up | Firewood per session |
|---|---|---|---|---|---|
| Stony 20 | – | 283 ft³–706 ft³ | 463 lb | 55–75 min | 15 lb |
| Stony 20 Through-wallThrough-wall | – | 283 ft³–706 ft³ | 463 lb | 55–75 min | 15 lb |
Heat-up and cost are our heat model's estimate for each size in a room at the middle of its range: indoor, insulated walls, 68 °F around the sauna, heated to 176 °F, one hour of bathing, electricity at $0.18/kWh (United States average). The maker does not publish this stove's output; the heat-up times use a rough figure from its room range.
Where to see it
Prices and availability come from the shop or maker and change; their page is what counts. Shop offers are added as retailers join.
Sources
- narvi.fi/en/product/narvi-stony-20/maker · read 2026-10-18
- narvi.fi/en/product/narvi-stony-20-through-wall/maker · read 2026-10-18
Other heaters for the same rooms
Questions and answers
What size sauna does the Narvi Stony heat?
Narvi rates the sizes for these rooms: Stony 20 283 ft³–706 ft³; Stony 20 Through-wall 283 ft³–706 ft³. Use your room's effective volume: add 1.2 m³ for every m² of glass, tile or stone, and multiply by 1.5 for solid log walls.
How long does the Narvi Stony take to heat up?
In a well-insulated room at the middle of each size's range, our heat model gives about: Stony 20 55–75 min; Stony 20 Through-wall 55–75 min to reach 176 °F. The maker does not publish the output, so treat these as rough; firing and wood make a big difference.
How many stones does the Narvi Stony take?
As stated by Narvi: Stony 20 463 lb; Stony 20 Through-wall 463 lb. Use the stone size the manual specifies and re-stack the stones at least once a year, replacing crumbled ones.