Heater for outdoor sauna, colder climate
I'm located in Manitoba, where winter temperatures regularly reach -30°C. I'm building an outdoor sauna with exterior dimensions of 8' deep × 7' wide, a sloped roof, and wall heights of 8'6" on the high side and 7'6" on the low side. The sauna will be fully insulated, including the floor.
Based on the finished interior dimensions (6'1" × 7'1") and average interior height, I calculate the sauna volume at approximately ~335 ft³.
Based on heater sizing charts, that puts me in the range of a 9 kW heater. However, both a local dealer and Homecraft have recommended a 10 kW unit.
I'm debating between:
- Homecraft Apex Mini 9 kW (32" tall)
- Homecraft Apex 10 kW (36" tall)
My concern with the 10 kW is the extra height. Following Trumpkin's recommendations, I'd like to keep the benches high enough that bathers are at or above the top of the stones, so every inch matters.
For those with experience in very cold climates:
- Would you choose the 9 kW or the 10 kW for a ~335 ft³ insulated sauna?
- Will a 9 kW heater struggle to maintain temperature during Manitoba winters?
- Will the 10 kW heat the sauna noticeably faster?
- Any experience with Wi-Fi vs. non-Wi-Fi controls in extreme cold? Any reliability issues?
I'd appreciate any real-world feedback, especially from people running similar sized saunas in cold climates. thank you in advance