What to Put Under a Fire Pit on Grass: The Best Materials and Practices

A fire pit is a wonderful addition to your backyard, creating a cozy space for outdoor gatherings, relaxation, and even roasting marshmallows. However, when placing a fire pit on grass, it's important to think about the safety, stability, and longevity of both the fire pit and the grass underneath. The heat generated by the fire can easily scorch or kill the grass, while the fire pit itself can shift or sink into the ground without proper support. To ensure safety, efficiency, and minimal damage to your lawn, it’s essential to put the right materials under your fire pit. This guide will explain the best options for creating a stable and safe base for your fire pit on grass.

Why Do You Need to Put Something Under a Fire Pit on Grass?

The ground under your fire pit can become scorched and damaged due to the high temperatures generated by the fire. Grass, soil, and any other vegetation will typically burn or die if exposed to the direct heat of the fire. Additionally, without proper support, the fire pit may sink into the grass over time, causing instability or making it difficult to move. For these reasons, placing the right materials under your fire pit helps protect your lawn, ensures safety, and prolongs the life of your fire pit.

Materials to Use Under a Fire Pit on Grass

There are several options for materials to use under a fire pit on grass. These materials help insulate the ground from heat, provide a stable surface for the fire pit, and prevent damage to the grass or surrounding area. Let’s take a look at the best materials you can use:

1. Gravel or Crushed Stone

Gravel is one of the most commonly recommended materials to place under a fire pit on grass. It serves several important purposes:

Heat Insulation: Gravel provides a layer of insulation between the fire pit and the ground, protecting the grass from the intense heat.
Drainage: The gaps between the gravel stones allow for water drainage, preventing puddles from forming around your fire pit and ensuring the base stays dry.
Stability: Gravel provides a stable foundation for your fire pit, preventing it from sinking into the ground or shifting around. It also makes it easier to level your fire pit.

When using gravel, it’s best to lay down a 2- to 3-inch thick layer over the ground. For added durability, you can use crushed stone, which is denser and more stable than regular gravel.

2. Sand

Sand is another effective option for protecting your lawn from the heat of the fire pit. Like gravel, it helps to insulate the ground and provides a stable base for the fire pit. It’s particularly effective at filling in any gaps around the edges of your fire pit.

Heat Protection: Sand absorbs heat, which helps prevent the heat from reaching the grass beneath. However, sand does not offer the same level of insulation as gravel, so it may need to be used in combination with other materials.
Smooth Surface: Sand creates a smooth, level surface for your fire pit to rest on, which can help keep it stable.

A 2- to 3-inch layer of sand is typically enough, but you can add more if necessary.

3. Fire Pit Mat or Fireproof Pad

Fire pit mats or fireproof pads are specialized products designed to protect the ground from heat damage. These mats are made from fire-resistant materials that can withstand high temperatures without burning or disintegrating. They are a great option if you want a simple, low-maintenance solution for your fire pit.

Convenience: Fire pit mats are easy to use and require minimal setup. Simply place them under your fire pit, and they will protect the grass from heat.
Portability: Fire pit mats can be moved around easily, making them ideal for those who want to relocate their fire pit or avoid permanent damage to their lawn.
Durability: Most fire pit mats are designed to last for several seasons, though it’s important to check the manufacturer’s instructions for care and maintenance.

These mats are usually made from materials like fiberglass, aluminum, or heat-resistant rubber, which provide a high level of protection from the heat.

4. Lava Rock

Lava rock is another option for under your fire pit. Lava rock is heat-resistant and provides excellent insulation between the fire pit and the grass. It’s a good material to use in combination with a fire pit that is frequently used or built into the ground.

Heat Resistance: Lava rock can withstand high temperatures without breaking down or deteriorating, making it an ideal material for fire pit bases.
Aesthetic Appeal: Lava rock has a unique look and can add an aesthetic element to your fire pit. It’s available in a variety of colors and sizes, so you can choose one that complements your outdoor space.

Lava rock is typically used as a top layer or decorative stone around the fire pit, but it can also work well underneath the fire pit if you want a more permanent base.

5. Concrete Pavers

If you’re looking for a more permanent solution, concrete pavers are an excellent choice. Concrete pavers provide a solid, stable foundation for your fire pit and prevent it from sinking into the grass over time.

Durability: Concrete pavers are long-lasting and provide a flat, sturdy surface for your fire pit. They are resistant to heat and weather, ensuring that your fire pit remains stable and safe for years.
Easy to Maintain: Concrete is low-maintenance and can be easily cleaned with a hose or pressure washer.

Concrete pavers are a more permanent solution and require more effort to set up. They are ideal for those who want a permanent fire pit installation or a more structured design.

Best Practices for Setting Up Your Fire Pit on Grass

In addition to choosing the right materials, there are a few best practices to keep in mind when placing a fire pit on grass:

Create a Safe Zone: Clear the area around the fire pit of any flammable materials, including dry grass, leaves, and branches. This will help reduce the risk of accidental fires.
Use a Fire Pit Ring: To contain the fire and keep it from spreading, use a fire pit ring made from steel or stone. This will help keep the fire controlled and prevent it from damaging the ground.
Maintain Your Grass: Over time, the grass around your fire pit may suffer from heat exposure. To help it recover, regularly water and fertilize the lawn, and consider replanting grass in areas that were damaged.

Conclusion

When placing a fire pit on grass, it's crucial to protect your lawn and ensure the fire pit remains stable. Using materials such as gravel, sand, or a fireproof mat can help prevent heat damage and maintain a safe, attractive outdoor space. Always consider safety when setting up your fire pit, and choose materials that will help preserve both the functionality and beauty of your backyard.