posted 1 day ago
If the stone is laid directly on the ground, most of the heat will go there via conduction. In a mild climate this might work, but anywhere that has cold winters will probably produce disappointing results. Getting a layer of insulation under the floor would be the way to go. I know a natural builder who has used a layer of biochar to do this, and put an earth floor on top of it. If you ran your heating tubes through the earth layer and put stone on top, you might have a solution.