Warm Glow patio heaters from Herschel Infrared: effective infrared heat
REALGLOW Spiral Flame Gas Patio Heater 13.5KW (Black with Black Cover)
REALGLOW Real Flame Outdoor Pyramid Patio Heater in Black - 13KW Propane Gas Standing Floor Heater for Outdoors & Gardens - Outside Space Heating for Decking, Home Garden & Gazebo : Amazon.co.uk: Garden
Best patio heaters 2023: Electric and gas options to heat your garden | Evening Standard