What to Put in Bottom of Fire Pit?

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When winter arrives and temperatures lower exponentially, you’ll want to have an outdoor place to spend without your friends and family without freezing. Here’s where a fire pit enters into action. 

Heating up the area, working as a stove, and sometimes even adding a unique look to the place – fire pits are never disappointing.

However, to build a fire pit, you’ll have to consider factors like the ideal place to prevent accidents and what materials you’re using to start the fire. More importantly, you’ll have to consider what to use for the bottom. 

The surface of any patio or backyard is susceptible to burns and horrible damage. And in most cases, it won’t help the fire start. With a suitable material, you can prevent that.  

Here, we will show you how to prevent that by picking the ideal material for the fire pit’s bottom. 

7 Materials to Use in the Bottom of a Fire Pit

With all the ideal factors for a perfect bottom of a fire pit, let’s take a look at the different materials you can consider: 

#1. Sand

Sand Firepit

Probably the most popular, and unsurprisingly, the cheapest. Sand of almost any kind will make for an excellent bottom of any firepit.

This happens because sand is easy to use, requires little maintenance, and still keeps the fire from spreading. What’s more critical, sand absorbs the heat and keeps whatever is below from getting damaged.

The best thing about sand is that it lasts a lifetime. A few hundred pounds of sand can stay in place for decades and give your fire pit a nice look nonetheless. 

#2. Dirt

Dirt firepit

Similar to sand, dirt makes for an excellent choice for your firepit bottom. The main benefit of dirt is that you can find it pretty much anywhere, from your own backyard or garden or neighbors. In case you need to buy your own, it is dirt cheap.

But dirt comes with a tiny problem: it burns. In contrast to sand, dirt will have a bit of organic matter that burns with the fire coming from the pit. This eventually makes it looks awful and often requires replacement.

Apart from that, dirt is not always non-flammable. Some dirt types (like garden or potting soil) may contain enough matter to produce fire themselves. They won’t fire up like kindling, but they may still help it spread. 

#3. Stones 

Stones firepit

Probably the safest alternative is a bed of stones. As simple as it sounds, placing rocks in the bottom of your fire pit will save you enormous dangers and maintenance efforts.

What sets stones apart is that they’re easy to find. As long as they’re small enough to produce a stable stone bed where you can place the pit on, you’ll have a perfect bottom to use.

One advantage of stones is that you can use them as an additional protective layer for the ground below. Placing the stones over sand or dirt, for example, can be an excellent way to increase the protection and still keep the fire going without any drawback. 

Also Read: How to Make a Rock Garden? Complete DIY Guide

#4. Gravel

Gravel Firepit

While you may argue that gravel and stones are the same things, you would be wrong. Gravel refers to small rocks, often slightly shredded, that you can spread across a particular area.

For a firepit’s bottom, for example, gravel works incredibly well. Like stones, it has no downsides, as it keeps the pit heated and maintains the base from burning.

Some types of gravel may actually add up to the place’s appeal. This can be an additional benefit from using gravel, especially when paired with how easy they are to bring around and pour on the area.

Additionally, gravel also works with sand and dirt, so you can combine them for even better results.

#5. Lava Rocks

Lava Rocks Firepit

Many people confuse gravel and lava rocks because they look almost the same. But they aren’t.

Lava rocks are specifically built to work as fire retardants while still working neatly to keep an area heated. Sounds counterintuitive, but it’s true. 

Also known as magma rocks, they also offer a fantastic advantage: they look fantastic. Boasting an often pink or reddish tone, these stones add up to your yard’s appearance. Especially if you have plants of similar colors or butterfly gardens around, using lava rocks can be a game-changer.

The only drawback is the price. While not necessarily expensive, lava rocks are a bit less affordable than other options in the list. 

#6. Fire Glass

Fire Glass

When it comes to boosting the patio’s appeal using exotic firepit materials, nothing compares to fire glass.

The name comes from the glass-like appearance of these small stones. Fire glass looks pretty much like expensive gravel, and that wouldn’t be far from the truth. 

These small shiny rocks come in all kinds of colors and shapes, but mostly small – like shredded rocks or glass. The advantage over other materials apart from the looks is that they’re a bit flammable.

You read that right. Fire glass works almost like coal itself. But despite that, it doesn’t spread the fire. When used in bottoms of fire pits, they keep the heat concentrated and the fire going for hours on end.

To make fire glass even better, it never wears off, maintaining the outstanding looks for decades. You’ll have to do little to no maintenance to fire glass. And it will still manage to protect the bowl or ground below. 

#7. Concrete Slabs

Concrete Slabs firepit

A lot of people will dismiss concrete as a bottom for the fire pit because it is bulky, expensive, and often harder to use. Yet, concrete slabs are probably the safest alternative you have.

Not only is concrete completely non-inflammable but it’s also highly resistant and will protect the ground from any burn. 

Apart from that, concrete lasts a lifetime and produces enough heat to keep the fire pit lighted up for hours. 

While it may feel a bit expensive and slightly complicated to use as bottom of a fire pit, it’s still a worthwhile alternative. 

You May Also Read: How Thick Should a Concrete Patio Be?

What to Use in the Bottom of the Fire Pit?

The materials you can use for the bottom of a fire pit will depend heavily on what you have available. But there are many other factors to consider, such as:

1. City’s Building Code

In some areas, the fire pit can only be made with specific materials. For example, you will need to use only gravel or sand. Other materials may be prohibited. Be sure to meet this code if you want to avoid possible issues later on.

2. Non-Flammability 

Whatever you pick for the bottom of the pit, it’s vital that it doesn’t catch fire. This often means materials like rocks and sand. Get away from mulch, wood, and grass that could light up and produce fires. 

3. Ground Protection

While not entirely necessary, it is worth choosing a material to keep the ground from getting burned. In case you want to remove the fire pit in the future, you’ll be glad that you chose a protective material. 

4. Good Looks

Probably the least important of all factors, but still worth considering. A good-looking material will make the area a lot more attractive, especially if the fire pit is already unique. The right material can boost the place’s appeal surprisingly well.

What Is the Bottom of a Fire Pit?

the Bottom of a Fire Pit

As the name says, it refers to the bottom of a fire pit. The place that separates the ground of a backyard or patio with the kindling or firewood. 

But more than a place, the bottom of a fire pit needs to be composed of materials that help the fuelwood ignite. At the same time, it needs to be sturdy enough to not get damaged and prevent whatever is below from getting burned.

 Apart from all that, the bottom of a fire pit is the first thing you need to prepare. In fact, it is the base of the whole fire pit, so it is essential to do it right. 

How to Build a Bottom of Fire Pit Safely?

With a better idea of the materials you can use for the fire pit’s bottom, let’s give you a few tips on how to build one properly:

Place it Far from Flammable Items

First and foremost, consider the bottom of a fire pit as the base. Here’s where the fire will start and will end. 

For that reason, it is vital to place it at least 10 feet away from any source of kindling. This means trees and shrubs, mulch, grass, wooden ornamentals, plastic and rubber objects, or pretty much anything that could light up.

Build Over Concrete

Most people build their fire pits over the soil in their patios. But the best alternative is always to build it over concrete.

While soil is not a bad idea, it may eventually ignite and produce unwanted results. Thus, it gets burned and damaged over time. Concrete, however, withstands the heat and fire while still preventing any possible spread. 

If you’re using concrete slabs as the bottom, you can overlook this tip.

Use a Bowl if Possible

Even though the bottom pit material can protect the ground and nearby stuff from getting damaged, you can always add a bowl for better results.

Metal bowls will host the flammable material (firewood, fire glass, coal, etc.) and prevent the fire from reaching the bottom. In case something does, you’ll have the bottom as an extra layer of protection.


So, did you learn what to put in bottom of fire pit? There are several options to consider, each one with its own advantages and disadvantages.

As long as you pick something that stays within your budget and delivers the performance you’re looking for, building that fire pit will be a no-brainer.

Now that you’re aware of what to pick – let’s get to work! That fire pit won’t build itself! 

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