Chemistry taught us that you can’t make a fire without a fuel source, heat, and oxygen. It might not be well-known, but you can’t just place wood on the ground and light it. You have to prepare the area so that the fire burns well and the surrounding area stays safe.
When building a fire pit, it’s important to remember that there are regulations for proper ventilation, so you should read up on your city’s requirements before deciding how many air holes you need.
Fire pits will not work well and can be dangerous unless they are ventilated. Without proper airflow, fires can die out, burn unevenly or weakly, build up too much heat, and damage the surrounding area.
Read on to learn why fire pits need air holes, how many they need, and the proper way to set up your own fire pit so that it burns effectively and is safe. After all, you can’t enjoy a relaxing fire if you or the area around you is at risk.
What is Combustion?
Combustion is the process of burning. In chemistry, however, it is a chemical reaction between substances. Before a fire can occur, there has to be a combustion between heat, fuel, and oxygen to ignite it.
Once the fire has started, it still needs heat, fuel, and oxygen to stay alight. You’ve got the heat and fuel parts down, they’re easy to maintain. Oxygen, on the other hand, can get a little tricky if the fire pit is not properly ventilated.
Why Do Fire Pits Need Air Holes?
If you’re using a fire pit, air holes are necessary or else the fire won’t burn fuel very well. It could also completely snuff out the flames. You can see this process in action by putting the lid back on a lit candle. The lack of oxygen will quickly extinguish it.
Insufficient air ventilation also lets too much heat build up in the fire pit which can damage any metal present at the bottom of the pit.
If it hasn’t caused the fuel to burn inconsistently or the heat to grow too much, insufficient air ventilation may cause damage to the patio, deck, or whatever structure is around it.
For these reasons, always buy or make a fire pit with air holes.
On some fire pits such as the Solo Stove, there are air holes at the bottom and top. This helps flow oxygen through to almost eliminate any smoke.
Types of Fire Pits
The first thing you should consider if you are using a wood-burning fire pit is where the safest place is to put it. Wood-burning fires crackle and pop and send out sparks to the surrounding area.
This means avoiding putting it near low-hanging trees, landscaping, or structures. Although the number varies based on where you live, the general rule of thumb is to keep a fire pit at least 10 feet away from anything flammable, especially your house.
Also make sure you have enough clearance above. Wood fire pits can be uncontrollable and can flare up if a piece of wood has some pitch in it. Gas fire pits on the other hand are very consistent. Watch for trees, roofs, walls, etc.
As for air holes, most premade wood-burning fire pits come with ventilation already designed into it, so you won’t have to do anything. If you have a walled, above-ground fire pit without air flow, drill 2” holes every 24-36″ around the base.
If you have a portable gas fire pit then it already has air ventilation installed. Read the manufacturer’s guide before using so your safety is ensured.
If you are installing a permanent gas fire pit, then be very careful to build it according to regulations, which includes proper ventilation equipment.
A fire pit fueled by propane gas specifically requires an air vent with an air mixer that works with it. This is extremely important because without proper air flow, the propane gas can pool at the bottom and possibly ignite, causing an explosion.
Gel fuel fire pits are becoming very popular because they don’t produce smoke or odor. A lot of people use tabletop gel fire pits which have their own air ventilation system. If you’re using a gel log (which can be used in any type of fire pit design) then apply the same rules of ventilation as you would with wood-burning or gas fire pits.
How To Build a Fire Pit with Proper Ventilation
If you don’t have a pre-built fire pit and you’re making one yourself, make sure it has sufficient air ventilation or else you could be putting yourself in danger or be stuck with a fire that burns terribly and causes excessive smoke.
Before you make a fire pit, make sure you have a way to put out the fire quickly in case of emergency. Fire extinguishers, sand, or water will do the trick.
Check your city’s regulations for fire pits. It’s best to go beyond their recommendations so you can be as safe as possible.
As for where to put the fire pit, make sure that it is far away from any structures or plant life that can be burned. There should be a lot of air flow around the area too.
When building the fire in the pit, don’t just lay all the wood down, you will need to cross it in a criss cross fashion as to allow airflow in-between the logs.
Try not to use any flammable chemicals like fire starters or gasoline when starting fires because it could cause damage to the pit itself and it could put you or people around the fire at risk.
Once the fire has started, don’t add anything with chemicals in it like plastic. It will release harmful fumes that can be dangerous to anyone around it.
Doing these things will give you the safest and most enjoyable experience with your fire pit.
To recap: fire pits need air holes. They simply won’t work without them. Since combustion requires oxygen, heat, and fuel to occur, it goes without question that air is necessary for the fire to continue burning.
If you’re buying a premade fire pit, read the owner’s manual to ensure that it is set up properly and safely.
If you’re making your own fire pit, check your local regulations for the requirements on things like air ventilation and physical location.
And last but certainly not least, always follow fire safety protocols. This not only prevents injury to you, but it also prevents damage or destruction of structures or wildlife.
Good luck and stay safe!