A beautiful blaze on a chilly night is a marvelous feature of camping. The flames dance, flicker, and light up your campsite. Roasted marshmallows and gooey s’mores add to the allure of a camping trip. As you stare into the flickering light, you might think, “How hot is a campfire?” We’re going to tell you.
The straight answer.
The straight answer is simple. The temperature inside your conflagration can reach higher than 2000° Fahrenheit. This is hot enough to melt aluminum, copper, and silver. A heat level like this is reached by a bonfire at its hottest point. Smaller burns will achieve slightly lower temperatures.
What about the glowing red coals at the bottom? These aren’t much cooler. Charcoal burns at temperatures in excess of 2010°. This means your coals are cooler than this if they aren’t burning.
How warm does your inferno feel when you’re sitting a few feet away? It turns out this is a very difficult question to answer. Modelling the temperature drop-off over distance is very, very hard. There are too many variables. One rule to help you, though, is this:
The heat transfer of a campfire is done by radiation and convection.
Radiated heat comes from the wood being burned. Convection is heat moving through air. More wood on the blaze produces more radiated heat. A big bed of coals sends out large amounts of radiated heat. To boost the warmth of your seating area, you should burn more wood. This isn’t true for cooking. The highest temperature of a huge bonfire is not much higher than the highest temperature of a small cooking circle. The radiation and convection of the bonfire are much higher, though.
How to get the best heat from your campfire
Understanding how your heat will be used is the key to getting the correct amount. There are different types of fires – hundreds of them! How hot is the campfire you need? You could build a tepee conflagration, a log cabin blaze, or a towering bonfire inferno. The purpose you have in mind determines the structure and heat you try to generate.
We’ve just mentioned some of the most common structures. These are easy to set up, burn well if the wood is good, and are simple to extinguish. If you master the tepee, the log cabin, and the bonfire, then you are well on your way to having a great blaze for every need. Let’s talk about why these configurations work so well.
Burning for warmth
A tepee works well for generating warmth because there is a large amount of wood involved. Even small tepees have eight or twelve small logs arranged in a cone. As these logs burn and turn into coals, the amount of heat being radiated is high.
Log cabin structures work well for radiated heat. They usually consist of two logs laid parallel to one another. Successive layers of parallel logs are added at 90° angles to the lower level. These mini infernos can easily use six or eight sticks about the same size as your forearm. Place kindling in the center of the square and light it up. As this blaze catches, the logs will burn and generate a great amount of radiated heat.
While the tepee and log cabin setups work well for general heat, they are not the best choice for cooking. A good cooking fire is smaller in size, easily controlled, and designed to accommodate your cooking pot. Here is how to build one:
- Lay two thick logs or long stones parallel to one another. The correct distance is determined by the diameter of your cooking pot.
- Then, build a small blaze between the logs or stones. Try to keep it small by using thin logs.
- As you build the cookfire by adding thin logs, your bed of coals will begin to develop. You can move the coals around and make an even bed below your pot.
- If the coals begin to cool too much, don’t worry. You can add more wood, blow on the coals, and add another small log or two. This will bring the heat back up to the best level for cooking.
Another great tip for cooking quality meals on an open fire is to use a system to adjust the height of your cooking pot. A simple tripod with a pot hook will work great. Ray Mears, the British master of bushcraft, has a brilliant way to make these.
Swedish fire torch
There are two other configurations you can use. The first is called a Swedish fire torch. This is a great setup for boiling water or cooking in a pot at high heat. Here is how you create it:
- Cut a 12-18” long section of a log which is 6-8” in diameter. The ends should be as square and flat as possible.
- Then, use an axe, splitting wedge, or even a saw to split the wood into quarter sections along its length. You should have a log in four sections.
- Separate the sections a little bit and then tie a rope or natural vine around the outside to hold it together.
- Stuff the cracks full of tinder and kindling. Light the tinder and let the log burn from the inside.
The middle of the segments will create a natural chimney to channel the heat upwards. Set your pot right on top of the log and you’re all done. Your coffee will be ready in just a few minutes!
Long log fire
The second useful blaze build is called the long log fire. You can use one of these to provide heat to an open shelter or even to a group of people sitting together at night. To get it set up, just follow these steps:
- Select long, thick logs to burn. You will want at least three. Each one should be at least six inches in diameter and equal in length to the area you want to warm.
- Lay two logs parallel to each other with three or four inches of open space between them. Put stones on the outside of the logs to prevent them rolling apart.
- At each end, insert two sticks about as thick as your forearm between the logs. These sticks should form an x. They will be used to support your third log.
- Fill the space between the two logs with tinder, kindling, and small branches.
- Lay the third log on top of other two. Take care to let it rest on the cross supports.
- Light the tinder at several different points along the length of the logs.
As the tinder and kindling catch, this long inferno will begin to pump out huge amounts of heat. Three thick logs will produce heat for several hours. As the logs burn, the top log will settle into the space between the bottom two logs. At this point, you can add another log or two on top to prolong the burn time.
A word on fire safety
Fires are hot! That’s what we’re trying to tell you. They are super useful tools for cooking, drying clothes, roasting marshmallows, and staying warm. Those comfortable blazes can also scorch people. Take care around every blaze. Here are some simple safety tips:
- Use stones or split logs to define your burning area. Doing this creates a visible safety zone for everyone on the camp site.
- Prepare for extinguishing the flames before you even strike a match. Have water, sand, or dirt ready to use in case things go wrong.
- Don’t build an inferno when a candle will work.
The Pacific Crest Trail association’s safety guide points out one great thing to remember: fire can smolder and even travel underground. When it’s time to put out your blaze, do so thoroughly. Pour water on it and mix the ashes.
Now you know how hot a campfire is: up to 2000° Fahrenheit. That’s hot enough to melt aluminum cans, start forest fires, and cook a beautiful backcountry bread. Used sensibly, the flickering flames can light up the night and create a magical camping experience. Kids love s’mores, hot dogs, and even steaks roasted over the coals. Just remember to keep it safe and keep it small. Get out there!