My wife and I love lighting a big fire in the backyard to cap off a day of entertaining. But building a pyre on the lawn left an ugly charred circle that grew larger over time. It made me cringe the next morning; it was like a visual hangover. We also worried that a wind-blown ember could torch the nearby woods.
I considered building a traditional brick fire pit on a concrete footing, but that’s no small undertaking or expense. The first step would be to dig a 30-inch-deep footing trench down through rocky soil. Then I’d have to get the concrete into the trench. Even if I opted to get the material delivered, it’s not easy lugging it by wheelbarrow. Mixing it by hand also seemed like a backbreaker. So I abandoned the idea of traditional masonry. Investigating chimineas and steel fire rings at a nearby home center, my wife and I discovered the Fossil Stone Fire Pit from Natural Concrete Products, a $500 kit of concrete blocks and a steel fire ring.
Much to my surprise, a buddy and I constructed the pit in 4 hours. When night fell, I kindled a big fire. Friends gathered, and I relaxed with a cold beer. The pit looked great and safely contained the fire without a burnt ring of grass the next day.

Prepare a Site:

Here’s what not to do: Build the pit under low-hanging limbs or power lines. Also, avoid putting it over or near a septic tank, leaching field, well head, or property line. Local laws will almost certainly require you to position a structure of this type a given distance from your neighbor’s plot, not to mention your own house. Check the codes at the town hall or the fire department.

After my buddy—Roy Berendsohn, Popular Mechanics’ senior home editor—and I had located the ideal spot in my yard, we drove a stake at the approximate center of the pit, looped a mason’s line around the stake, and then tied the line around a can of white landscape spray paint, with which I created a 102-inch-diameter circle. This is large enough to accommodate the pit, whose outside diameter is 66 inches, and a surrounding 18-inch band of River Jacks gravel.To create a base for the pit and gravel, we dug a hole 4 inches deep bordered by the painted circle and dumped in enough crushed stone to fill a few wheelbarrows. (I used 2A Modified, a common road-building material in my area; check for something similar at your local stone yard.) After raking the stone to a depth of about 2 inches, we compacted it with a hand tamper.

For aesthetic reasons and to ensure the fire-pit blocks align properly, it’s important to build the pit’s walls on a level surface. So we marked a 68-inch-diameter circle (a couple inches wider than the outer wall of the pit) on the compacted stone, then used a 4-foot mason’s level to check the surface. We weren’t as fussy about leveling the rest of the stone, since it would be covered just by the gravel.

Build the Pit:

The fire-pit wall consists of two layers of wedge-shaped concrete blocks, each with a clearly marked top and bottom. The inside edge of each block sits 24 inches from the center of the pit. After we positioned one block, we placed each successive one snugly against the next. The process was simple, like completing a puzzle, with the last block of the first tier neatly completing the circle.

Before installing the second layer, we placed a straight piece of lumber on top of the first one and used the level to make sure we were on the mark. We laid up the second tier, staggering the blocks to ensure that the seams didn’t line up; this improves the wall’s stability.

Next, we bolted together the two steel pieces that form the fire ring, placed it in the pit, and tapped it with a rubber mallet to get it to settle into the crushed stone.

Fill the gap between the fire ring and the wall with crushed stone.

After backfilling the space between the ring and the inside of the wall with more crushed stone, we added the cap, first laying the pieces in position and then gluing each one into place with a quarter-size glob of masonry adhesive. Finally, we ringed the pit with gravel.



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