Stone or ceramic have a greater thermal mass than wood, so the main difference is in how long it would take to get the sauna hot.  The mechanism in how the sauna's air is heated with IR heaters is different than with a traditional sauna heater.  The IR radiation strikes the wall surfaces and heats these surfaces.  These in turn end up heating the air.  In a traditional sauna heater the air enters the at the bottom and is heated directly and comes out at the top.  In either case, if you want the air to be hot, you need about 16 Watts/cubic foot.

If you arrange the IR heaters so they are close to your body, then the IR radiation strikes your body and warms your skin.  In this case you can end up sweating without the air temperature being that hot.  Keep the panels low as possible .

Dieter Jung

Northern Lights Cedar tubs Inc.