Abstract: A patio heater, has: a base to be supported on a ground; a stem protruding upwardly away from the base; and a heat generating device secured to the stem, the heat generating device having: a burner fluidly connected to a source of a fuel to be burned; a diffusion sheet enclosing a combustion chamber, the burner located inside the combustion chamber and surrounded by the diffusion sheet; a reflective shield located above the diffusion sheet; and at least one reflective fin mounted to the diffusion sheet and extending away therefrom.