Clay chimineas need sand or another insulating material to protect the clay from the heat of the fire in a chiminea. This can seem like a huge chore and an extra expense when you’re first setting up your chiminea – so, do you really need it?
Unfortunately, yes, you do need sand (or an alternative) if you have a traditional clay chiminea.
Why Put Sand in the Bottom of a Chiminea?
Clay chimineas need a base layer of insulating material that separates the fire from the bottom of the chimenea to:
- Stop heat from damaging the bottom of your fire bowl
- Stop heat from damaging surface chiminea is sat on
- Prevent against the corrosive nature of ashes
What Kind of Sand Should I use in a Chiminea?
Any sand that is clean and dry can be used to line the bottom of a chiminea.
How much Sand Do I Need?
This will depend on the size of your chiminea. You should aim to fill the fire bowl 3/4 of the way (or just a few inches shy of the lower lip of the front mouth).
TIP – After you put the sand in, your chiminea will be considerably heavier. Make sure it’s in the right position to avoid heavy lifting.
bETTER Alternatives to Sand
Sand is cheap and available everywhere. However, the main drawback of sand is it likes moisture and will hold onto it. It’s also difficult to clean and may require a lot of sifting if you want to reuse it.
Although sand creates a good buffer for heat, it doesn’t let air move around under the fire.
TIP – When using sand as your insulator, many people use a few bricks or something similar to create a platform for your fire. This helps with ventilation.
Other popular alternatives to sand in a chiminea are:
- pea gravel
- lava rock
Lava rocks are the best option for insulating the bottom of your clay chiminea. In addition to excellent insulating properties, they are lighter than sand and easier to clean. Because of how well air circulates around them, even if they get damp – they usually dry quickly.
Can I use Play Sand in My Chiminea?
Yes – play sand is just sand that’s been cleaned and filtered. Remember sand is made up of many materials in tiny pieces so to make it safer for kids it’s washed extensively to get rid of any nasties and in the process, it also rounds out the grains of sand making it safer for kids to play with.
Always check the labels of any product to make sure there is nothing unexpected in there that could be flammable or hold moisture.
If you’re looking for more safety tips specific to clay chimineas, check this article.
Do you have to put sand in the bottom of a steel chiminea?
Putting sand in the bottom of a steel chiminea is not necessary as steel behaves in a very different way to clay when exposed to heat. Steel will be far more durable to the effects of the fire heat and far less likely to crack.
A few reasons you might consider using sand in the bottom of a steel chiminea:
- If your chiminea is designed where the bottom of the fire bowl is close to the ground. This would be particularly important if planning to use your (low-bottomed) chiminea on a deck.
- Sometimes the design of chimineas firebowl (the bit where the fire sits) is a bit too deep and bulbous. This resutls in the fire itself sitting a bit low. By using sand you can prop up the fire so you can keep the size of your fires small but still be seen.
Can I use Soil Instead?
Nope. Soil is a bad idea because of the level of moisture it contains. It’s also messier, dirtier, and full of all sorts of material.
Should I Put Sand in My Cast Iron Chiminea?
This is not necessary. Cast iron can cope with much higher temperatures than clay and therefore, an insulating material in the bottom of the fire bowl is not required.
Often cast iron chimineas come with a grill that sits inside the fire bowl so you can build the fire on top of it. This lets air circulate all around the fire and adds to the efficiency of your chiminea.
Do All Clay Chimineas Need Sand?
You will need to regularly clean out the sand in the bottom of your chiminea and replace it with fresh sand. Keeping some sand nearby when your chiminea is lit is always an excellent safety precaution.
In the event of your fire getting out of control or if you need to extinguish it immediately – use sand.
TIP – if you have any trouble lighting your fire check that your sand is not damp – this can make things tricky to get going.
Where Can I Buy Cheap Lava Rocks?
The best place to pick up lava rocks cheaply is Amazon. Other places do offer them cheaper but when you add on the delivery cost, they come out more expensive.
On Amazon, you can purchase a 3kg box for just around £8 at the time of writing.
Clay chimineas need some sort of insulation in the bottom to prevent the heat from the fire from damaging the structural integrity of your chiminea.
If you do end up with a crack in the bottom fire bowl region of your chim, it’s usually game over and not something you can patch up. Cracks here are extremely difficult to repair as not only does this part support the weight of the fire but also heat will just get in the cracks and make them bigger.
I hope this article helps explain the mysteries of sand and chimineas. If there’s anything I missed, let me know!
Check out this article on how to light a chiminea.