Protect Your Patio! What To Put Under A Firepit & Why


photo of firepit with firepit mat

It’s no secret that fire pits can help enhance the ambiance and utility of your backyard. However, you may have also discovered that they can do a bit of damage to a grass lawn, wooden deck, and concrete floors if not well handled. Let’s go over some of the materials you can use in and under a fire pit to keep the base it’s on in the perfect condition.

The most useful items to protect your grass, concrete and wooden patios are:

  • fire mats
  • pavers
  • natural stone
  • lava rocks
  • volcanic ash
  • sand

Where To Buy A Firepit Base

You can easily find most of these items at your local hardware store like Home Depot or Lowes. If you are looking for firepit pads, you are more likely to find more choices online. A big 67×60 inch firepit mat like this one on amazon is well-reviewed and stores very well.

Tip: You can often find people trying to get rid of their excess sand, pavers, and tile on local marketplaces like offer up, craigslist, or Facebook marketplace. These are generally much less expensive than buying new!

Why A Firepit Base Is Necessary

Not all materials have the ability to withstand the high temperatures that firepits emit. Wooden decks, grass lawns, and concrete pavements are susceptible to catching fire, sparking, and exploding if a fire gets too hot. Firepit bases help shield the patio material underneath from the heat and embers created by the firepit. So, now that we have the why out of the way, let’s go over each of these materials and see how they help protect your patio.

Related: If you are wondering if a smokeless firepit is a better fit for you, I wrote an article about it here.

Materials That Go Under A Firepit

Items that go under firepits are designed to keep the raw heat from the firepit away from the patio. They act as a cushion between the two. These are generally less aesthetic, but they are better at reducing the amount of heat your patio must endure. These materials are:

  • Firepit Pad – this helps to protect your concrete from cracking and your wood and grass from scorching. You still need a raised firepit for most firepit pads. 10 inches minumim is the standard distance from the firepit to the patio surface.
  • Bricks or Pavers – raising your fire pit on a platform creates a heat shield for the patio below. These are great to use in conjunction with a firepit pad, or on their own.
  • Marble, Slate, and Granite – these are dense materials and thus less likely to crack and explode under heat. Firpits usually do not have to be raised if placed on these types of stone.

Materials That Go In A Firepit

These materials are much more aesthetically pleasing, they also have the added benefit of keeping the bottom of the firepit free from direct fire as these can evenly distribute the heat reducing the wear and increasing the longevity of your firepit. These materials include:

  • Sand – placing sand underneath your heat pit helps distribute the heat evenly and acts as an insulator.
  • Lava Rocks – fantastic at absorbing and distributing heat, these also come in many different shapes and sizes.

The Best Materials To Use Depends On The Patio Type

Everyone’s situation is different. People have different patio types and different priorities in what they want from their firepit experience. Let’s go over the most common types of patios, which base materials pair well with them, and why.

What To Use Under A Firepit On Grass

Imagine you want to relax in the backyard with family and few friends. The problem is, you don’t have a specially built fireplace and your manicured lawn is the only spot to set up a portable fire pit. Grass is definitely the least forgiving to firepits and a majority of the time I would say to either buy a specially built firepit or dig up enough dirt to make a firepit area. Still, grass is a viable option to put your firepit on, with some proper setup first.

Tip: Before setting up and using your firepit, it is a great idea to wet the area around the firepit with a hose. This will help keep the grass green by protecting it from any stray embers.

The best things to use under a fire pit on grass are:

  • Firepit Pad – this helps to protect your grass and keeps embers from the grass
  • Bricks or Pavers – raising your fire pit on a platform creates a heat shield for the grass below
  • Sand – placing sand underneath your heat pit helps distribute the heat evenly and acts as an insulator
  • Marble, Slate, and Granite – these might be good choices if you would like a more semi-permanent base. These are dense materials and thus less likely to crack and explode under heat
firepit on concrete

What To Use Under A Firepit On Concrete

Most gas and wood-burning fire pits spot a copper, steel, or wrought iron bottom that can burn any heat-sensitive materials placed underneath, including concrete. Concrete flooring is fairly heat resistant, but ambient temperatures are not the same thing as direct heat from a firepit. That being said, concrete, especially polished or stamped concrete can crack under intense heat unless you use some sort of protection.

The best things to use under a firepit for concrete are:

  • Bricks or Pavers – simply lay the concrete pavers or fire bricks between the fire pit and your concrete-floored patio. One step above this, would be be to stack them with little gaps between them, this allows for more airflow and a place for the heat to escape.
  • Sand – you may be able to get away with just using a good layer of sand in your firepit. This would depend on the quality of your firepit as well as the type of concrete flooring you have. Sealed concrete may fair better than a polished concrete in this aspect. This also keeps the aesthetics.

What To Use Under A Firepit On Wood

Lighting a fire pit on a wooden deck can be disastrous, especially if you don’t take some precautions. A wooden deck can fuel the fire you are trying to light up because wood is highly susceptible to burning. Here are a few bases you can use on top of your wooden deck:

  • Sand – Spread a fine layer underneath your heat pit to provide extra screening on top of your wooden deck. Sand protects your wooden floor by absorbing and redistributing the heat evenly above the wooden floor.
  • Landscaping Tiles – You could use these as a permanent flooring in combination with other heat-resistant surfaces to protect your wooden deck.
  • Pavers – Temporarily arrange bricks underneath your fire pit to create an elevated, fireproof insulator to protect your wooden deck entirely from even the most intense heat. Just make sure to cover your flooring completely.

Tip: Placing a protective pad under the bricks may reduce scratches and dents from the heavy bricks.

Final Thoughts

Camping around a fire pit is a terrific way to spend time with loved ones outside as you bond and create memories. However, some care must be taken while handling them to prevent the risk of fire or injury. Using a base for your fire pit isn’t 100 percent necessary, but it can extend the life of your fire pit and your patio!

Michael Carpenter

Hi, I'm Mike. I grew up in North Carolina having a blast on trampolines, go-karts, and just sitting on the porch with my friends. I have since moved to Las Vegas with my wife, 2 children, and 3 dogs. When I'm not chasing the kids around the house, I am probably chasing them around the backyard!

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