How much lava rock do I need for my fire pit?

It depends on the size and depth of your burner pan. Measure the inside length and width of the pan (or the diameter for a round pan) and how deep it is, then check the coverage information on the product page to find the right amount. If you'd rather not do the math, give our NFI-certified team your burner pan measurements and we'll tell you how much to order.

How deep should lava rock be over the burner?

Most burners need about 2 to 4 inches of media covering the burner ports to spread the gas evenly and produce a natural-looking flame. Piling media much deeper than that can restrict the gas flow and make the flame weak or uneven. In deep burner pans, lava rock is often used to fill the space below and around the burner, with the top layer kept to the recommended depth. Always follow your burner manufacturer's guidelines.

Why does lava rock pop, and how do I prevent it?

Lava rock is porous and can absorb water. If wet rock heats up too quickly, the moisture inside turns to steam and can cause the rock to pop or crack. To prevent it, let the rock dry completely after rain, run the flame on its lowest setting for several minutes before turning it up, and keep your fire pit covered between uses so the rock stays dry.

Do I need to rinse new lava rock?

Yes, it's a good idea. New lava rock often has dust and small fragments from shipping. Rinse it with a hose before installing it, then let it dry completely before lighting the fire pit.

Can I mix lava rock with fire glass?

Yes, it's one of the most popular combinations. Use lava rock as the base layer to fill the burner pan, then add fire glass on top for sparkle. Lava rock costs less than fire glass, so this approach lets you fill a deep pan without buying as much glass. Keep the combined media over the burner within the depth your burner manufacturer recommends.

How do I clean soot off lava rock?

Let the fire pit cool completely, then remove the rock and rinse it with a hose on low pressure. For heavier soot, soak the rock in a mix of water and white vinegar before rinsing. Let it dry completely before returning it to the burner pan, and start the fire on a low flame the first time. If soot keeps building up, check that the rock isn't packed too tightly over the burner ports.

Fire Pit Lava Rock & Stones

Lava rock is one of the most popular fire media for gas fire pits, and for good reason. It spreads the gas evenly for a natural-looking flame, holds up to high heat, and costs less than other media. Use it on its own for a rustic look, or as a base layer under fire glass or fire balls.

Why Use Lava Rock in a Gas Fire Pit?

Lava rock is porous volcanic stone that handles high heat and lets gas flow through it easily. That makes it a reliable way to cover your burner and diffuse the flame so it rises evenly across the fire pit. Its natural texture and earthy color fit traditional, rustic, and transitional outdoor spaces.

Lava Rock as a Base Layer

Many fire pit owners use lava rock to fill the bottom of a deep burner pan, then add a top layer of fire glass, fire balls, or fire pit logs. Because lava rock is lighter and less expensive than other media, it reduces the amount of decorative media you need while still covering the burner fully.

Lava Rock and Natural Stones

Along with classic black and red lava rock, we carry tumbled stones and pebbles that give your fire pit a smoother, more refined look. Choose a size that suits your burner pan: smaller pieces fill tight spaces and narrow burners, while larger pieces work well in wide fire pits.

How Much Lava Rock Do You Need?

Most burners need about one to two inches of media covering them. Measure the length and width of your burner pan, decide how deep you want to fill it, and use the coverage information on the product page to estimate how much to order. Always follow your burner manufacturer's guidelines for media depth.

Tips for Using Lava Rock

Lava rock is porous and can hold moisture. If it gets wet, let it dry completely before lighting your fire pit, and run the flame on low for the first few minutes. Heating wet rock too quickly can cause it to crack or pop. Rinse new lava rock before installing it to remove dust, and keep your fire pit covered between uses to keep the rock dry.

Frequently Asked Questions

How much lava rock do I need for my fire pit?
It depends on the size and depth of your burner pan. Measure the inside length and width of the pan (or the diameter for a round pan) and how deep it is, then check the coverage information on the product page to find the right amount. If you'd rather not do the math, give our NFI-certified team your burner pan measurements and we'll tell you how much to order.
How deep should lava rock be over the burner?
Most burners need about 2 to 4 inches of media covering the burner ports to spread the gas evenly and produce a natural-looking flame. Piling media much deeper than that can restrict the gas flow and make the flame weak or uneven. In deep burner pans, lava rock is often used to fill the space below and around the burner, with the top layer kept to the recommended depth. Always follow your burner manufacturer's guidelines.
Why does lava rock pop, and how do I prevent it?
Lava rock is porous and can absorb water. If wet rock heats up too quickly, the moisture inside turns to steam and can cause the rock to pop or crack. To prevent it, let the rock dry completely after rain, run the flame on its lowest setting for several minutes before turning it up, and keep your fire pit covered between uses so the rock stays dry.
Do I need to rinse new lava rock?
Yes, it's a good idea. New lava rock often has dust and small fragments from shipping. Rinse it with a hose before installing it, then let it dry completely before lighting the fire pit.
Can I mix lava rock with fire glass?
Yes, it's one of the most popular combinations. Use lava rock as the base layer to fill the burner pan, then add fire glass on top for sparkle. Lava rock costs less than fire glass, so this approach lets you fill a deep pan without buying as much glass. Keep the combined media over the burner within the depth your burner manufacturer recommends.
How do I clean soot off lava rock?
Let the fire pit cool completely, then remove the rock and rinse it with a hose on low pressure. For heavier soot, soak the rock in a mix of water and white vinegar before rinsing. Let it dry completely before returning it to the burner pan, and start the fire on a low flame the first time. If soot keeps building up, check that the rock isn't packed too tightly over the burner ports.