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How To Build a Circular Built-in Fire Pit

A photo collage showing on how to build a built-in ciccular fire pit.

A fire pit is one type of outdoor fire feature that is an inexpensive, easy way to add a lot more fun to your backyard.

While you buy all kinds of fire pits, it’s also easy to build your own fire pit.

This extensive article steps you through how to build the two main types of fire pits: in-ground and above-ground.

Here we go.

1. DIY Above-Ground Built-In Fire Pit

DIY Veneer Patio with Firepit

We’re here today to help you build a small, combination fire pit and patio area. When we crafted this project ourselves, the dimensions kept expanding, leaving us with a sizable flagstone patio and sitting wall. We hadn’t previously done a masonry project, so we turned to internet how-to videos and relied on classic trial and error. The aim here is to assist anyone wishing to do a similar type of project.

The most important lesson learned from this project is this: flagstone is a time sink. If you want a quick and easy build, try a wall block or a stack rock veneer, or other options like uniform patio pavers, as flagstone varies in size and thickness, making leveling a challenge.

Our finished product isn’t perfect, but we are still very pleased with the results.

Tools needed:

  • shovel
  • wheel-barrow
  • pic
  • trowel
  • rake
  • circular saw (with masonry blade)
  • rock hammer
  • rock chisel
  • access to the water hose
  • dust masks
  • level
  • sponges
  • buckets
  • rubber mallet
  • tamper

Materials list (approximate):

  • Quikrete  (40 bags of 60 lb)
  • Mortar (30 bags of 60 lb)
  • concrete blocks – Qty 60
  • cap block-  Qty- 24
  • 1/2 ton of yellow sand
  • 1/2 ton of #7/8 gravel
  • 1/2 ton of ‘thin flagstone’
  • 3/4 ton of ‘standard flagstone’
  • firepit ‘kit’

Total Cost: $1500 (approximately)

Phase 1: Digging out the hill

Digging out the hill

Digging out the hill

Digging out the hill

First, eyeball and dig out the shape that you want. Begin scooping out dirt. Make sure you have a place to put it, and save some for later purposes of back-filling the wall. Next, dig out a 20′ footing (16″ wide and 16″ deep). Level out the footing and patio area.

Phase 2: Dig and Pour the Footing

Dig and Pour the Footing

Dig and Pour the Footing

Dig and Pour the Footing

Dig and Pour the Footing

Close up - Dig and Pour the Footing

Close up - Dig and Pour the Footing

When researching what type of base is necessary for a sitting wall we discovered that most sources said a 16″; x 16″ footing with a gravel base (10 bags of all-purpose gravel from Home Depot in our case). So, level the rock base out, then use 18 bags of 60-pound quikrete, which you can mix by hand in a wheelbarrow. Pour this over two rows of rebar set on bricks.

You can simply mix the Quikrete fairly runny and pour evenly throughout. Try to make this as level as possible. Let it completely set

Phase 3: Drystack

Drystack blocks

Drystack blocks

Lay the blocks out dry to ensure they fit. If they look good, mix a mortar to begin wet laying the blocks.

Phase 4: Mortar the Blocks

Mortar the Blocks

Mortar the Blocks

Mortar the Blocks

Mortar the Blocks

Mortar the Blocks for Veneer Patio with Firepit

Note: you may want to try a concrete adhesive here. Probably cleaner and simpler than mortar.

Mix a 60lb bag of mortar with just over 1 gallon of water until the mix is somewhere in viscosity between peanut butter and oatmeal. Lay it on with a trowel, aiming for a smooth surface and level blocks. Next, pour quikrete down the open cells of the blocks for extra strength. We went back and added a row of blocks behind the original for a thicker wall. Add cap blocks and fill gaps with more mortar,

Phase 5: Mark Out The Full Patio

Mark Out The Full Patio and Lay Gravel Base

Mark Out The Full Patio and Lay Gravel Base

Mark Out The Full Patio with blocks

Your patio may change in shape and size as the project proceeds; ours did, starting as a semi-circle that became a full circle and merged into an oval.

Now, dig another footing in order to use blocks to contain the patio. Without it, the project may wash away with the first big rain!

Phase 6: Spread a Layer of Gravel and Sand

Spread a Layer of Gravel and Sand

Spread a Layer of Gravel and Sand on the Foundation

We obtained a half-ton of 7/10 gravel from a local supplier (at $28) and spread it over level ground. Tamp this down using whatever you can – we used an improvised tamper (patio umbrella base w/ broken shovel, that worked like a charm) but any method you use should be ok. This should make for about 4″ worth.

Next, we used a half-ton of yellow sand from a local dealer ($28 again) and spread it out in anticipation of laying your flagstone. Tamp this down as well to level, keeping a slight slope away from the wall. This will hopefully end up being about 2-3″ thick.

Phase 7: Locating the Veneer

Locating the Veneer

We found the veneer (less than 1″) flagstone at a local dealer, priced at about $280 per ton. This project required about $180 worth.

Phase 8: Mortar Veneer On Wall

Mortar Veneer On Wall

Mortar Veneer On Wall

Mortar Veneer On Wall

Mortar Veneer On Wall

Note: This process is better off completed *after* laying the floor, but being pressed for time, and not having the floor pieces available, we began anyway.

Begin the process of putting a scratch coat of mortar on the block wall. This allows for better adhesion when you apply the veneer itself. Using a trowel, place 1/2″ of mortar on each stone along with a gap in the middle for suction to the wall. Start low and work from the bottom up. With the curved shape of the wall, vertical placement for large stones may be more flush than horizontal, so you may place a couple of them that way too.

Tap each one on using a rubber mallet and leave a 1/2″ gap between each piece. Where big gaps are left, you can fill in with smaller stones as needed.

Phase 9: Lay Patio Stones

Lay Patio Stones

Lay Patio Stones

Lay Patio Stones

Lay Patio Stones

In making sure the stones lay level, we made a limited amount of cuts with a skill saw and masonry blade, scored the stone, and used a hammer to shape it.

Once confident that you can level the stones out, begin lifting them one at at time and placing a quikrete sand/topping mix (requiring only water) that lifts each stone in an even fashion to that of the thickest stones.

Phase 10: Add Mortar/Grout

Add Mortar/Grout

Add Mortar/Grout

Add Mortar/Grout

Mortar and Grout Completed

We had seen on various videos how easy a grout bag is to use, so we went out and bought one. If the mortar doesn’t flow easily, do as we did, and take out the trowel and use it to fill the gaps along with a sponge to wet down the excess mortar. This will be a long process that you may want to break up into sessions.

Phase 11: Add Fire Pit

Add Fire Pit

Our pit happened to come from the rock store where the flagstone was obtained. It was a $300 kit, which was very reasonable after pricing out other options that require fire brick as a lining and plenty of other rock to make an eye-pleasing centerpiece.

Once crafted, you’re good to go! We have a bit of landscaping work to finish here, as you can see. Your results may vary, but even an imperfect product will remain a beautiful place and social center in your yard for years to come.

Project tutorial provided and republished with consent by alr227.

2. DIY In-Ground Fire Pit

Illustration of a DIY fire pit

This is a simple illustrated tutorial on how to build an in-ground courtesy of


Once you have your plan in mind, your next step is to pick the perfect spot. Evaluate your space. How much room do you really have? While there’s a fire pit to fit any space, you’ll want to know exactly what you’re working with before you get to the dirty part of the job.

If you have a large piece of property, you can be a little free while selecting the spot, but you’ll still want to make sure the spot you’ve selected is safe and convenient.

You’ll want to begin by checking your local ordinances and HOA rules to make sure you’re following all regulations. Plus, then you can be sure that your HOA won’t show up in the middle of your project and tell you that you have to demolish all your hard work!

The area you pick will want to have at least seven feet clear all around it, so you can be sure that you have enough seating. You’ll want the space to be flat and about ten feet from the nearest structure and plants. No fires here!

You’ll also want to consider what direction your prevailing wind blows in at, to avoid smoke and embers blowing in your face.

Illustration of where to build a fire pit in your backyard

Choose Your Style: Custom, Prefab, or Portable

Once you’ve selected the perfect spot, it’s time to decide which style direction you want to go in. Will you want a permanent or portable fire pit? Portable can be a great option for those who have limited space or want to take it camping.

Permanent or portable, both options come in a ton of shapes, sizes, materials, and design styles. You can opt to have your permanent fire pit custom built, or, if you’re handy, build it yourself.

The options are many, and whatever you choose should depend entirely on your taste, available space, location, and, of course, your budget.

The different fire pit styles

How to construct a simple in-ground DIY fire pit (4 easy steps)

If you are crafty and want to build your own, you can at a very reasonable budget. Check out the following directions to build your very own fire pit!

4 steps for building a simple in-ground fire pit

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