I am looking around at getting a new stove to replace my old pre epa one and am a little confused trying to figure out clearances. The stove area now the back wall is Cinder blocks with stone mortared on it (non combustible) but the other side of this wall is a room with drywall on the back side. Would my clearances go to the beginning of the drywall on the back or start right at the stone since its not spaced off of the drywall or anything. This is a difference of about 10" between the two