No pun intended here but fire pits are sizzling right now! They have become all the rage to host your outdoor entertaining, and they provide a comfy, snug place for backyard campfires year round.
There are thousands of reasons to build a fire pit in your yard, but before you install any, it’s crucial to make sure the materials you choose are actually safe.
To be specific, rock seems the most fireproof material on the planet. But most seasoned campers will tell you that the wrong type of rock can explode in your fire.
Upon the matter, exploding rock is more prevalent than you realize, so the right type of rock is imperative for your fire pit.
So In this Article: We will explain why you should use caution with rocks and stones for your fire pit, and direct you to safe materials like lava rock that are less likely to turn into cannon balls once exposed to heat!
Using the right materials keeps your fire pit safe
It’s so easy to believe you can throw whatever you want in your fire pit.
However, for safety, you have to think about the fire pit structure and the materials you are actually burning since it is likely that many of the materials you think are fireproof, weren’t really made to be exposed to a prolonged heat source and flame.
Sand, gravel, and many kinds of rock just cannot handle the blistering heat of the materials you may use in a fire pit and will explod.
Additionally, large river rocks and boulders can look stunning, but some of them may crack or explode as well, so exercise caution when using them.
If you want to use rock deep inside your fire pit, you can consider using lava glass beads, lava rock or similar types of filler on a stone or concrete base, but use caution since ash and lava rocks still ignite or explode in heat.
Using volcanic ash has also been used as a filler material when building fire pits.
Some rocks can explode in a fire
Keep in mind that with sufficient heat, any wet rock will generally explode!
Specifically, porous rock that have air and moisture pockets will shatter as the fire heats the water and air, causing it to expand extremely fast.
Absolute no-nos for your fire pit rock include:
- River rocks
- Pumice
- Gravel
- Limestone
- Sandstone
These rocks are known to absorb water and have a much higher probability of exploding in sustained heat than harder denser rocks like marble, slate, or granite.
Lava rock is another one of the safest types of rocks to use in a fire pit, along with fire rated brick, concrete and lava glass.
Be cautious as thin gravel or lava rock may hold moisture if its rained recently, even these rocks can explode if fully saturated or concealed when put in fire pits.
The best practice is to keep any rocks in your fire pit as dry as possible. If you can, make an effort to cover when it is not in use.
Lava rock is one of the best choices for a fire pit
Known as basalt, lava rock is famous as a good structural and filler material for a safe fire pit.
Since lava rock is not flammable, you don’t have to worry about it potentially catching fire while you are using your fire pit.
As a lava rock would indicate, it acts well under high heat conditions, which would take temperature levels well beyond those achievable in your fire pit for any physical or chemical change to occur.
It is called lava rock as it originates from the lava of a volcano and is one of the most common rock types, comprising as much as 8% of the earth’s surface.
The popularity of a fire pit is that lava rock is widely available and very inexpensive, allowing you to obtain enough lava rock to fill your fire pit as you want. You can find lava rock in any hardware store or garden centre.
One very important thing to remember about lava rock is that it retains heat very well.
This means that it is likely the lava rock will still be red hot, hours after you have fully extinguished the fire.
Just because the rest of the fire surrounding it has cooled, does not mean that it is safe to handle the lava rock.
Make sure the lava rock has cooled completely or it can cause a nasty burn. Make sure you keep animals and kids away from the fire pit area with a barrier preventing access to the heat.
Other safe materials for your fire pit
Having the correct materials can really elevate the look of your fire pit and still be practical and safe around an open flame.
If you feel like lava rock is a little too bland for you, this list offers some great options for a chic fire pit display.
Natural Stone
Natural stone is a highly desirable material for creating a durable fire pit.
Solid choices are granite, marble, or quartz chips that do not spark or spread flames.
As long as the porosity is low and the thermal resistance is high, they are a fireproof option that can give you peace of mind.
Refractory bricks
Fire bricks are a form of clay brick that will not crumble under high temperatures when it is incorporated as a structure in a fire pit.
These fire bricks are also kiln-fired to ultra high temperatures make them larger and denser than regular building bricks.
Although fire bricks cost more than regular brick, they have longevity and can be exposed to fire over and over.
Porcelain
Although it is a fragile material, porcelain is actually really durable and works well as a base for a fire pit when using porcelain tiles.
Before building the fire pit, you should check with the porcelain tile’s manufacturer to make sure it’s grade is suitable to withstand high heat and flames.
Cast-on-site concrete
Concrete that is poured on-site is a dependable fireproof material that you could use for a modern or minimalist fire pit or reline an existing structure.
Choose a commercial-grade blend with high early strength. You could also choose to mix stone, gravel or sand with the cement mixture to obtain an optimal combination.
Ceramic logs
Ceramic logs are emerging as an attractive decorative feature.
The logs look just like your typical wooden logs but are able to withstand high temperatures and still keep your fire looking great after the wood has been burnt away.
Additionally, they are also smoke-free!
Steel and iron fire pit logs
Steel and iron fire pit logs and stone are a low maintenance feature, which retain some heat and radiates to the last moments of the night.
Their heat dispersal makes them ideal for cold weather and other tough conditions and they gracefully age as they become sooty, rusted and weathered.
Ceramic glass
Ceramic glass refers to a special kind of transparent ceramic that is sold as chucks or chips, for use to decorate the surface of a small firepit.
Fire glass
Fire glass is specially treated glass that will hold up to the heat from your fire.
You can add it safely to your fire pit as chips, cubes, diamonds, crystals, beads and glass pebble. Fire glass is also available in many colors.
A fire pit liner can also add a layer of protection when using rocks and stones
Using stainless steel, concrete, iron or copper insert liners will safeguard the rocks and stones in your fire pit from direct heat.
If you have a sunken fire pit, liners are a great choice as they will provide an effective barrier against underground root fires and also give the pit additional support.
They create a tidy, clean finish, and make maintenance and cleaning simpler.
If you use a liner, make sure you maintain airspace between the pit and the liner.
Last-minute fire pit safety tips
While a fire pit is undoubtedly a location to sit back and relax, your safety is most important.
These quick tips will help you keep yourself, your family, and your property safe when they visit your fire pit.
Make sure that you comply with city codes
Examine local building ordinances and city codes to ensure that your fire pit is authorized and compliant.
In many areas, open fires and fires of wood are prohibited.
There may be restrictions on what you can start and when you can start it.
If you are in doubt – Get advice from your local fire department.
Permanent or portable?
Determine whether you want to create a fire pit that is permanently raised or sunk in the ground, made of brick or stone, or whether you want to create a fire bowl or fire table.
If you self-build, make sure you are conscientious about materials to make sure that you are not using porous materials, which could explode when heated.
Location
When choosing a place for your fire pit, make sure that you are more than 10 feet from buildings and other structures that could burn such as fences and trees.
Ensure the fire pit will be a safe distance from any potential awnings, branches or vegetation that could touch their branches or become ignited from flying sparks or flames escaping from the fire pit.
If the fire pit is sunken, please check with utility companies to ensure that excavating the fire pit will not break or disturb any utilities.
Supervise the fire at all times
Regardless of if your fire pit is outside, you should never leave it unattended.
You should never allow the fire pit to burn overnight.
Children and pets should never have access to the fire pit area until the fire is gone completely!
Means of extinguishing the fire
Always keep a large bucket of water or hand-held extinguisher nearby for quick action if needed.
Do not add any fuel to the fire at least 30 minutes to 1 hour before you want to extinguish it.
Let it burn down and put all remaining embers out. Remember that stone and metal may still be extremely hot after flames have died down.
Rounding up
Fire pits provide a wonderful reason to spend more time in your backyard. Not only are they functional, but a well-constructed and good-looking fire pit can actually add to the value of your home!
It’s tempting to want to make your fire pit with large smooth boulders, or even gravel, but proceed with caution.
The last thing you want to happen is for your home’s fire pit, which is meant to be enjoyed, turns out is a danger to your family.
Avoid any explosions by using true fire resistant materials like lava rock, or others that are dry and in a controlled fire.