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How to Clean Lava Rocks in Your Fire Pit or Grill

How to Clean Lava Rocks in Your Fire Pit or Grill

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Lava rocks look fantastic and function great in a gas barbecue or fire pit. However, because they are so porous, they gather dust quickly and can get really dirty from grease and food residue. One has to be careful with how you clean them to ensure that no moisture remains in the rock – this can cause them to explode in the heat of a fire!

To clean lava rock without using water, turn them greasy side down on the grill, place some aluminum foil over them and then turn the grill on for 30 minutes to burn off the grease and grime. You can also soak lava rock for a day in hot, soapy water – but be sure to dry them thoroughly.

It can be tricky to clean large quantities of lava rock at a time. We spoke to some people who have been using lava rocks in their grills and fire pits for many years to learn their tricks for keeping lava rocks nice and clean.

Why Is It Important to Clean the Lava Rocks in a Fire Pit?

Lava rocks are essential in a gas fire pit or barbecue to protect the burner and distribute the heat evenly. But if you use lava rocks for this purpose, they do inevitably get covered in grease and grime when you grill meat.

Because of how porous the lava rocks are, they can actually absorb grease like a sponge!

Cleaning your barbecue lava rocks is just as important as cleaning the grill grates, exterior and base of the barbecue. A good pitmaster keeps their grill in good nick.

You need to clean the lava rocks from time to time; otherwise, the burner may become blocked with food particles, reducing the efficiency of your grill.

Dirty lava rocks also cause flare-ups – intense bursts of flames due to grease catching alight. These can ruin whatever you are cooking by charring it excessively. Flare-ups are also dangerous, as they can lead to a grease fire.

How Often to Clean Lava Rocks

It is advisable to clean lava rocks each time you finish using your grill, especially if the meat that you are cooking is saucy, juicy, or fatty, causing a lot of dripping on the rocks. Cleaning them each time will eliminate the risk of flare-ups altogether.

However, not everyone is this diligent when it comes to barbecue maintenance. Aim to clean the lava rocks every second or third time you grill. If you notice the number of flare-ups increasing, it is definitely time to give your lava rocks a clean!

Best Way to Clean the Lava Rocks in a Gas Grill

The easiest and safest way to clean lava rocks is by burning the grease off of them. Here’s how:

  • When you are finished using the grill, switch the burner off to allow the lava rocks to cool down.
  • Once they have cooled, use a pair of tongs to flip the lava rocks over so that the greasy parts are facing down towards the burner.
  • Use a piece of aluminum foil that is large enough to cover all the rocks to place over the grill. The foil will radiate the heat from the burner inwards, helping the grease burn off quicker.
  • With the lava rocks covered, turn the burner on so that the grill can heat up.
  • You should notice smoke coming from beneath the foil – this means that the grease is burning up.
  • Leave your grill on with the lid open for half an hour.
  • If you still see smoke coming off the rocks after the time is up, and the rocks still look greasy, allow them to burn for another 30 minutes.
  • Thereafter, your lava rocks should be clean, and your grill will be ready!

How to Clean Lava Rocks with Water

Another way to give your lava rocks a deep clean is by using good old soap and water. It’s good to do this once every six months, or at least once a year, depending on how often you use your barbecue.

Remove the rocks from the grill and place them all in a bucket of hot, soapy water. Water alone cannot dissolve grease, so adding dish soap is key.

Allow the lava rocks to soak for at least an hour or up to a day, depending on how grimy they are. When the lava rocks are done soaking, empty the water out and replace it with cold water.

Let the lava rocks soak in cold water for an hour. This gives the soapy water inside the rocks’ pores time to escape.

Rinse the lava rocks well with clean water. It works well to lay them all out on the lawn and spray them using a hosepipe.

The Dangers of Cleaning Lava Rocks

As mentioned earlier, lava rocks are porous, similar to a sponge. One problem with using water to clean your lava rocks is that water gets stuck inside the rocks.

If lava rocks are still moist inside, when you heat them up in the fire pit, they will explode! The water in the rocks’ pores expands as it turns into steam, and this pressure causes the rocks to blow apart.

Exploding lava rocks are dangerous to anyone sitting around the fire pit. Therefore, it is critical to dry your lava rocks thoroughly if you wash them with water or if they get rained on.

How to Dry Lava Rocks Properly

Drying lava rocks correctly takes a bit of time, but the process is absolutely necessary. If the rocks are soaking wet, lay them out in the sun to dry first.

When the outside of the rock feels dry, place all the lava rocks into the fire pit. Light the fire pit and turn up the heat.

Place a metal grate over the top of the fire pit to prevent pieces of exploding rock from flying out of the pit. While the fire pit is burning, keep a safe distance from the pit – at least 15 feet.

Allow the fire pit to burn for ten minutes. You should hear popping noises when the rocks start to explode. Keep the fire pit burning hot until you hear the popping come to an end. It can take 45 minutes to an hour for the rocks to dry completely.

Once you have completed this process, you can safely sit around the fire pit as usual without worrying about any bit of rock hurtling your way.

Maintaining Your Lava Rocks

To keep your lava rocks clean and to ensure that they last a long time, you should get into the habit of flipping the rocks over regularly. This will prevent the heavy buildup of grease and food particles on the rocks.

How often you flip the rocks depends on how frequently you use the grill. If you cook on it every day, then you should flip the lava rocks over every two weeks. If you cook on the grill once a month, you can get away with flipping them every six months.

Handle your lava rocks with care when you flip them and when cleaning them. If they bump and scrape against each other, they get damaged.

Another good way to keep your lava rocks well maintained is to place a waterproof cover over your grill or fire pit when it is not in use. The more times they get wet and need to be dried, the more wear they undergo.

Keeping your lava rocks well maintained will mean that you will not need to replace them as frequently.

When to Replace Your Lava Rocks

Lava rocks are not meant to last forever. The more you use your fire pit, the more frequently you will need to replace your lava rocks. Generally, lava rocks last for about a year or two.

As the lava rocks move and knock together, small bits will break off, the rocks will crack, and they will become smaller over time. When the lava rocks weather down, they are not as effective at keeping grease from dripping down onto the burner.

When your lava rocks get old, they will start looking a bit crumbly. This is a sure sign that you need to replace them.

Recycle Old Lava Rocks from Your Fire Pit

It can feel wasteful to throw your lava rocks in the trash once they have served their time in the fire pit. Luckily, there are a few different ways you can recycle your old lava rocks.

Because of their porosity, they are an excellent soil amendment. They retain water and help to regulate the soil temperature. Crush your old lava rocks and combine them with potting soil to create a mulch for your garden.

Lava rocks are great for improving drainage in plant pots. Add them to the base of planters before adding the rest of the soil. This is a brilliant way to use old lava rocks.

Many people use lava rocks as a ground cover in flower beds and for landscaping. They reduce water evaporation from the soil surface, making your garden more water efficient.

Chipped lava rock is a fantastic, green alternative to asphalt or concrete for garden paths, walkways, and driveways. While you do need quite a large quantity for this, you can always use your old lava rock from the fire pit to add to the lava rock you buy from a landscaping company.

How to Dispose of Old Lava Rocks

You cannot dispose of old lava rocks in your regular recycle bin! There are far more responsible ways to dispose of them.

Your local landscaping supplier should happily take your old lava rocks off your hands. But be sure to clean them before taking them to be recycled.

Another way to get rid of them is to rent a dumpster. This is the best way to get rid of heavy waste that cannot go in your household garbage, like gravel and rocks.

Alternatives to Lava Rocks That Are Easier to Clean

Fire glass is a commonly used alternative to lava rocks in fire pits. Unlike normal glass, which will shatter under intense heat, fire glass is specially tempered. It does not melt, shatter, or burn.

Fire glass does need to be cleaned as often as lava rocks, and it is much simpler to clean. You can simply rinse the layer of soot that builds up on them off with water.

If you want your fire pit to have a more polished aesthetic, fire glass is for you! It sparkles beautifully and can be used in indoor or outdoor fire pits.

Ceramic briquettes are a brilliant alternative to lava rocks in a gas grill. Composed of charcoal, coal, and wood dust, they work exactly like lava rocks.

They are much easier to clean because they do not absorb grease. They are a longer-lasting alternative to traditional lava rocks.

Ceramic tiles are another alternative to lava rocks in a barbeque. They allow grease and oils to pass through holes in the tiles. Before the grime can land on the gas burners, it burns up, making the tiles clean and easy to use.

Final Thoughts

Cleaning the lava rocks in your fire pit or gas barbecue is critical to keeping your grill running the way it should. You will not need to clean lava rocks that often if you get into the habit of turning them often. How frequently you use your grill will determine how often you should clean your lava rocks.

To clean your lava rocks without water, simply burn the grease and grime off of them by placing aluminum foil over the rocks and switching the burner on. One can wash them using soap and water, but if you do this you have to dry them thoroughly to prevent moist rocks from exploding in your fire pit.

When your lava rocks have done their time, and no amount of cleaning will refresh them, you should either recycle them or dispose of them responsibly. Generally, lava rocks should get replaced every year or two.


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