Open-air heating: a challenge
Heat is generated in closed rooms according to the laws of physics. A radiator heats air close to the ground, which then rises and pushes the colder air down again. This creates a cycle that can also be used to heat sheds or summer houses, for example. The principle doesn’t work without a ceiling and walls. This makes heating in the open air – like around a campfire, for instance – more of a benefit for the soul than for the body.
A covered patio is necessary to ensure that you really do feel the effect of the warmth and don’t have to put on your winter coat, scarf and lambskin boots. It’s even better if there are one or two side walls. But even then, you should be aware that a lot of heat will still simply be lost. The energy consumption – and hence the costs – are significantly higher than when heating a comparably large enclosed space.
However, there are several options for patio heating that will allow you to continue to spend time sitting comfortably outside, even in the colder months. We present these devices below.
A heating mushroom: effective, but controversial
We have all seen these massive metallic structures with their fascinating, threatening-looking flame, mainly on café terraces or at private outdoor parties. If you stay quite close, then the heating mushroom – also called a gas radiant heater – can do a very good job of warming you up. If you come too near, it can sometimes even get too hot.
A heating mushroom is usually operated by gas from a propane gas cylinder which is located in the base. Another advantage besides its effectiveness is its mobility. You can install it anywhere on the patio, move it when the wind changes, and bring it closer if you’re feeling too cold. Of course it must be placed on solid ground and comply with fire protection regulations. Information about this will be given in the instructions.
The biggest disadvantage of a heating mushroom is its enormous energy consumption. A standard gas bottle will last for ten hours. In addition, gas-powered heating mushrooms cause excessive environmental pollution because CO₂ is released when the gas is burned. In many cantons this has resulted in a ban on gas heating mushrooms in public areas. You may continue to use them privately.
Nevertheless, some much more environmentally friendly alternatives now exist. Devices referred to as eco-heating mushrooms generate the same heat radiation as conventional heating mushrooms with a lower calorific force.
A commercially bought product: pellet-fired patio heaters do not use gas at all. They have a cartridge that is filled with small pieces of wood along with a wood wool lighter and pellet starter before being ignited. The flame begins to heat up in no time. One refill – about eleven kilograms of pellets – continues to burn for about three and a half hours. The device costs 3,240 francs (price on 09 November 2020).
Gas-powered heating mushrooms are controversial because of their high energy consumption. There are other alternatives that are better for the environment.
Radiant heaters: reflected heat
With this type of device, it’s important that the patio has as many walls as possible. This is because a radiant heater doesn’t heat the air like other devices, but instead heats elements in the surrounding area. When the rays hit a solid body, for example a wall, heat is generated. This in turn is reflected and multiplied. The extent to which the respective body or material heats up depends on its composition and the radiant intensity of the heater.
There are three types of radiant heater:
- Conventional electric radiant heaters with heating rods
- Infrared heaters
- Infrared dark radiators
Their common feature is that they run on electricity. This means you will need a power socket on your patio, or at least nearby. They are also noiseless and odorless. They can be turned on immediately by pressing the start button – no pre-heating is necessary. There are differences in the way they are assembled: some devices can be set up freely, others need to be mounted on the ceiling or wall. The electricity consumption of all radiant heaters is quite high, which will affect your utility bill.
Infrared dark radiators are most suitable for use on patios, because unlike infrared heaters, they don’t emit light. This will make the atmosphere a little more pleasant for you in the dark in the evening, whilst also protecting the habitat of animals and plants.
A commercially bought product: the TrendHeat TH-3200 aluminum radiant heater is ideal for use on the patio. Once mounted on the ceiling, it can heat an area of about 30 square meters. Its maximum power is 3,200 watts. As it is a dark radiator, it doesn’t emit any disturbing infrared light. It costs 1,190 francs (price on 09 November 2020).
Fire bowls and fire baskets: for cozy evenings
One important point to note in advance is that fire bowls and fire baskets have open flames burning inside. You must therefore always take the necessary safety precautions.
After all, wood is burned in fire baskets and fire bowls – just like on a traditional campfire, but in the restricted space available in the container. That’s where the romantic campfire atmosphere comes in – but the heat generated provides only limited protection against frosty temperatures, as it soon dissipates. A pleasant atmosphere is created nonetheless. But what’s the difference between a fire bowl and a fire basket? You can find out here:
- Fire bowl: either a powder-coated steel pan that can be fueled with coal or wood, or a non-frost-resistant ceramic pan that should only be used with wood. Some bowls are placed directly on the floor, while others have legs. One very special type is the gabion fire bowl, named after the wire basket filled with stones that it stands on.
- Fire basket: a metal basket coated with black powder to make it weatherproof. The closer the iron rods are to each other and the more tightly the seams have been welded, the higher the quality of the product. There is an incandescent bowl under the fire basket that protects the ground from scorching.
A commercially bought product: the Quader XL H300 gabion fire bowl consists of a stainless metal basket measuring 59 x 59 x 30 centimeters. The stones to place inside are not included, but the bowl is. If you leave out the bowl when assembling the structure, you can also use it as an open campfire. It costs 129 francs (price on 09 November 2020).
An Aztec stove: exotic heating
An Aztec stove is a somewhat unusual way of generating heat on the patio. This traditional fireplace from Mexico stands out primarily because of its bulbous shape. Firewood is added through one or more openings, and the smoke escapes upwards via a chimney flue. The terracotta that is traditionally used looks attractive, but does not withstand extremely high temperatures. Other materials such as steel are more robust.
A commercially bought product: the “Aztekenwürfel” (Aztec cube) 80 patio stove gets its name from its fire chamber, which is cube-shaped rather than round. It has openings on all four sides for adding firewood. The main body is made of raw steel connected with brass screws, and the hatches are made of fireproof glass. Attention: at 80 kilograms, this monster is no lightweight. And at the hefty price of 5,800 francs (price on 22 December 2020), it doesn’t exactly come cheap either.
The options at a glance
Heating mushroom
- Advantages
- Disadvantages
- Very powerful heating effect
- High gas consumption
- Mobility
- High emission levels
Price: around 200 francs
Infrared dark radiator
- Advantages
- Disadvantages
- Instantly ready for operation
- Power connection necessary
- Protects animals and plants
- Covered patio required
Price: around 1,000 francs
Fire bowl/fire basket
- Advantages
- Disadvantages
- Low acquisition costs
- Open flames
- Campfire romance
- Low heating effect
Price: around 100 francs
Aztec stove
- Advantages
- Disadvantages
- Extraordinary design
- Takes up a lot of space
- Powerful heating effect
- High price
Price: around 6,000 francs
Conclusion: pleasant moments, even in winter
By using a patio heater, you can defy the cold temperatures and continue to spend time outside even in November, December and January. There are various types of device available, ranging from the fire bowl to the Aztec stove. They differ greatly in price but also in appearance and functionality.