How much space do you need to heat? Most free-standing propane heaters have a heat output of 40,000 Btu or more. Manufacturers often claim this can raise outdoor temperatures by anywhere from 10 to 25 degrees within a radius of nine feet. However, owner-written reviews indicate these estimates are exaggerated. In reality, the heating range is more like three to five feet or less in cold, windy weather. The smaller tabletop models, which produce only 10,000 Btu or so, may only provide warmth within a couple of feet of the heater. If you want to heat a large area, experts advise placing multiple heaters eight to 20 feet apart. An overhead canopy or awning can also help contain heat.
What is the weather like in your area? Patio heaters work best in mild climates. If you live in a very cold or windy area, you may need multiple heaters to provide enough warmth. Wind can also affect heaters in other ways. Propane heaters may be harder to light, and open flames may blow out if the wind is strong enough. A high wind also poses a tipping issue for narrow heaters, especially lighter tabletop models. If you live in a windy area, it's especially important to choose a patio heater that is heavy and stable, or consider a radiant electric heater. The best models have a switch that will automatically shut the heater off if tipped. Finally, if it rains frequently in your area, look for a model with a rust-resistant finish. If you choose a fire pit, make sure it comes with a cover to keep it from filling with rainwater.
Do you want to move the heater around? Many outdoor fireplaces, especially gas-powered ones, are very heavy and will be all but impossible to move once you've set them up. Smaller fire pits, by contrast, can be moved around the patio or even taken along on trips. Tabletop propane heaters are very portable if they use a 1-pound propane cylinder but not when hooked up to a heavy 20-pound propane tank. Free-standing propane heaters are usually weighted to keep them from tipping over, so if you want to move yours around, look for a model equipped with wheels. Electric heaters are limited to outlet availability, as they must be plugged in.
Can someone help with the assembly? According to reviewers, assembling many of the heaters in our report is really a two-person job, despite what the manufacturer promises. If you plan to assemble the unit on your own, choose a model that is fairly simple to build.
Do you have children? Electric patio heaters are the most kid-safe type since there's no flame. Propane heaters often come with features to make them safer to use around children. Look for child-proof connections, well-balanced bases and most importantly, an automatic tilt shut-off feature, which shuts off the heater if it tips over. Also, make sure the heat-producing parts are well above a child's height and that models with wheels don't move when they are standing.
Infrared patio heaters appear to be on the decline. Most of the models we reviewed five years ago are no longer available, and we found very few models with strong reviews, if any. However, some manufacturers are introducing a new type of electric heater, which uses halogen light bulbs to produce heat. These heaters usually resemble table, floor or hanging lamps but are much more powerful. They are also weatherized for outdoor use. So far, there is not enough feedback on halogen patio heaters to give a clear indication if they are worth the money or if they are any better than propane or infrared models. We will continue to track this new trend and review any notable models as they develop.