When I built a cattle panel grow-house, I didn't see anything about heating it in the winter. I wasn't about to buy or built a regular wood stove but I instead went with a scaled down rocket mass heater.

This is a 5" system with a 31 gallon galvanized trash can and 4" galvanized chimney. The core is all 1.25" fire brick with refractory mortar.

If you would like me to draw up plans for this, I can but there are many plans already out there. Let me know if you have any questions about the grow-house and/or the stove. Thanks for watching.

The stove fan: https://amzn.to/3HEtpdX
The infrared thermometer: https://amzn.to/3RJCB5p
The bluetooth thermometer: https://amzn.to/3DM7i4h