How to Build a Gas Fire Pit

Your guide on how to build a DIY fire pit from scratch!

GETTING STARTED

Before you start thinking about making a gas fire pit from scratch, you need to nail down a few details first. We’ll break down the decisions you have to make and all of the parts you’re going to need, then walk you through the building process!


DETERMINE YOUR LOCATION

Surface

Ideally, you’ll want to build an outdoor fire pit on a flat, level surface, like a stone patio, deck, or flat yard.

For installations on grass and decks, you’ll need to use a non-combustible base underneath the fire pit to prevent radiant heat from transferring to the surfaces and starting a fire.

For grass, you can use a layer of sand or pea gravel as your non-combustible base. For decks, you can use bricks, pavers, Hardie Board, or Dura Rock.


Proximity

We recommend that your fire pit has at least six feet of clearance around the sides and above the burner area.

Once you choose the type and size of your burner, you’ll want to double-check the manufacturer requirements to make sure you have adequate clearance to combustible materials.

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Check any city ordinances to make sure your fire pit is legal and will be up to code.

CHOOSE YOUR GAS TYPE

Natural Gas

Natural gas requires a permanent gas line to be installed before building your fire pit. This costs more upfront, but the cost to operate a natural gas fire pit is lower than one fueled by propane. You'll also never run out of gas.


Liquid Propane

Propane offers you a little more flexibility with installation. You can choose to hook-up a 20lb propane tank for quick installation, or if you have a large propane tank on-site, you can have a permanent gas line routed to the fire pit.

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You’ll need to hire a licensed gas plumber to run a permanent gas line to the fire pit location.

Read more on the benefits of each fuel type here.

SELECT YOUR ENCLOSURE

The enclosure is the body of a fire pit. It houses the burner and gas and ignition components. You can construct the fire pit enclosure on-site using masonry bricks, or you can buy an unfinished enclosure, which can be purchased separately or in a kit.

DIY fire pit kits take the guesswork out of building a fire pit from scratch. Most come with all of the components you need and either include masonry bricks that you stack yourself, or an unfinished enclosure.

VENTILATION

No matter what type of outdoor gas fire pit you're building, you'll need to include ventilation in the base. Ventilation provides fresh air for the ignition system to work, allows for continuous airflow and water drainage, and prevents excess gas and heat from building up inside the enclosure.

Without proper ventilation, the buildup of gas and heat could lead to a potentially hazardous situation, like an explosion. Ventilation should include at least two built-in air vents on opposite sides of the fire pit.

If your fire pit doesn't have an open bottom, you can create adequate airflow by using risers to elevate the fire pit off of the ground.

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Liquid propane is heavier than air and will sink to the bottom of your fire pit. Install the air vents on opposite sides of the fire pit at the bottom of the base. Natural gas is lighter than air and will rise to the top of the fire pit. Install the air vents on opposite sides of the fire pit at the top of the base. 

CHOOSE YOUR BURNER & COMPONENTS

Burner

Burners are the most important feature of your gas fire pit. They are used to burn the gas and will determine the size and height of the fire.

Burners come in several shapes, sizes, materials, and BTU capacities. You’ll want to research the types available and their BTU outputs to ensure you get the proper flame presentation.

You can buy a burner individually or get a fire pit burner kit that comes complete with all of the components you need to set it up.

Check out our deep dive on fire pit burners to learn more!


Pan

Pans sit directly underneath the burner and hold the media (like lava rock or gas logs). Some burners come with pans attached to them, but others require the pan to be purchased separately.

If you're buying a pan separately, you'll need to consider the size and shape of the fire pit, and if you'd like the pan to be recessed into the surface or sit flush with the top.

The pan's diameter needs to be large enough to provide approximately three inches of clearance from the sides of the burner to the edge of the pan.


Connectors & Fittings

Connectors and fittings are small parts that sit inside the enclosure and are used to route the gas to the burner. We recommend using a whistle-free flexible line to connect the gas source to your ignition system.

Avoid using corrugated pipe, elbow connectors, and sharp turns in your flex hose, as they will result in unpleasant whistling.

Gently curving the flex line during installation will result in optimal gas flow and prevent whistling.

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You can avoid low flames and poor burner performance by making sure you have the right size gas line to supply enough fuel to the burner. If you have an existing gas line that's the wrong size, you can have it modified by a gas plumber.


Air Mixer

Propane fire pits require an air mixer. Air mixers work by drawing in fresh air to mix with the propane before exiting the burner for combustion. They need to be installed vertically and as close to the burner as possible.

If an air mixer is installed horizontally or it’s connected to an elbow, the air will slow down, causing gas to leak out and resulting in flames underneath the pan.

The manufacturer of the burner generally determines the type of air mixer you need.

A burner system like the CROSSFIRE Brass Burner doesn't require an air mixer since it has small air mixers in each jet.


Media

Media sits on top of the burner and pan to disguise them from view and helps to distribute the gas evenly to create a natural flame pattern. For a traditional look, we recommend a ceramic gas log set or lava rock media. For a modern look, we recommend colored fire glass, fireballs, or firestones.

With proper gas pressure, media should only cover the burner by one-inch.

If you're using a burner with jets, like a CROSSFIRE, you'll cover only the tube with media and leave the jets exposed (the media can sit flush with the jets, or the jets can stick out a little above the media).

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Liquid propane will leave a sooty residue on fire glass. Use darker colored fire glass or lava rock to hide the appearance of soot. If you prefer lighter colored fire glass, you can easily clean the residue off by removing the fire glass and washing it in a bucket of soapy water. Let it air dry before placing it back on the burner.


Ignition System

The ignition system is used to start and control the fire. You have the choice between a match-lit (manual), push-button, or automatic ignition system.

Automatic ignition systems are the most expensive and typically require an electrical connection, but they are also the simplest and most convenient to use.

Automatic ignitions can be controlled with a wall switch, remote control, Bluetooth, or smart home system.

PUTTING IT ALL TOGETHER

Now that you have all of your components picked out, we’ll walk you through how they fit together in both manual and automatic ignition systems.

Before we dive in, it’s important to note that this is not something you should do yourself. When it comes to gas and electrical installations, it’s imperative to have them done by licensed professionals.

If your gas line and connections aren’t hooked up correctly, it could lead to a very dangerous situation and ultimately result in serious injury or even death. Always take the safe road and hire a professional!


Manual Ignition

First, the gas line is routed to the location for the fire pit, and the enclosure kit is placed on top.

Next, one side of the key valve is connected to the gas stub and the other to the flex hose. The flex hose is connected to an air mixer (only with propane), then the air mixer to the pan and the burner to the pan.

Before setting the burner and pan in place, you’ll test for gas leaks at each connection (burner to air mixer, air mixer to flex hose, flex hose to key valve, and key valve to stub).

After the gas connections are tested and ready to go, you’ll set the pan and burner into place.

Next, you’ll check the ignition and burner to make sure the gas is flowing adequately, and the burner is producing the desired flame presentation.

The flame pattern may not look completely accurate at this point since there isn’t media on top to disperse the gas flow, but you’ll be able to see if the gas pressure is off (low flames) or if the burner isn’t working correctly.

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This diagram illustrates what installation will look like with a push-button ignition.

Once you’ve determined everything is working as it should, you’ll turn the fire pit off and fill the pan with media, adding enough to cover the burner by one-inch (let the burner cool first).

Next, you’ll finish the outside of the enclosure with your desired finishing material.

Finally, turn it on, make sure the flames look good, and sit back and enjoy the fire!



Automatic (Electronic) Ignition System

Automatic ignition systems require both gas and electricity to function. Most automatic ignitions are hardwired, plugged in, or battery powered. How you want to control the fire pit will determine how your electrician will do the installation.

You should also consider including a gas shut-off valve approximately twenty feet away from the fire pit. This will ensure you can cut the gas supply off to the fire pit in case of an emergency.

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Any fire pit that we sell for a commercial application (restaurant, hotel, multi-family application, etc.) must include an automatic ignition system, emergency stop button, and a timer.

First, gas is routed to the location of the gas shut off valve, then to the fire pit. Next, if you have hardwired power, a junction box will be installed remotely from the fire pit, and for plug-in power, an outdoor-rated outlet will be installed inside the fire pit.

From here, you’ll follow the manufacturer instructions for installing your particular automatic ignition system.

When it comes time to test your gas connections, you’ll also need to check the automatic ignition system to make sure your electrical connections are working.

Once you’ve determined the gas and electrical systems are working as they should, you’ll add the media, covering the burner by one-inch, finish the enclosure, then run another test fire to make sure the flames look good.

Sit back and enjoy!

WE'RE HERE TO HELP

Still need help building your fire pit? Call our NFI certified experts at (844) 264-2855, and they’ll walk you through the process!

MORE RESOURCES:

Save time and money with these simple do-it-yourself fire pit kits.

Read this handy guide to find out which gas type is right for you.

Not sure which fire pit burner is best? Here are our top gas fire pit burners kits to help you get started!