Glass-tube patio heaters, often pyramid shaped, are trendy now. They bring a fire element and create quite a show at night. You can stand right next to them, and you can touch them while they are lit. That is because the quartz glass fire tube is an insulator. What all effective patio heaters have in common is that they have a radiator: A material that radiates heat. In our review of glass-tube, or lava-tube heaters, we have been unimpressed with their heat output. In fact, we have yet to meet anyone, other than a manufacturer's representative, who says glass-tube heaters heat well. What is a fire-tube heater? It is a very-expensive-to-run lava lamp. That is why we don't carry them at Alfresco Heating.