Select Location and Shape
First and foremost, when building a fire pit you must select a location that is a safe distance from any structures or low hanging trees.
Choosing the shape of your fire pit will determine how many blocks you will need. Most fire pits will be three to four feet across.
- For a fire pit ring, you need trapezoidal blocks, which are narrower on one side. This allows the edges to fit snugly together for a circle without creating any gaps.
- A square fire pit uses rectangular blocks and can be constructed in a variety of patterns with blocks of different shapes and sizes.
Mark and Prepare Site
Outline what will be the footprint of the fire pit to mark your work area.
- If you are building a circular fire pit in your yard, drive a stake at the center of what will be the fire pit location.
- Use marking paint tied to a string to draw a circle around the stake.
- The diameter of the circle should be slightly larger than the outside dimensions of the fire pit ring you’re preparing to build.
- For a square or rectangle fire pit, temporarily lay out the first layer of concrete blocks for your design on the ground and check the layout for square. Use a shovel to outline the perimeter and then remove the blocks.
- Remove the sod and dirt to a depth of about seven-inches from inside the perimeter that you marked. Keep the excavated area level as you work.
- Pack the dirt solidly all the way around with a hand tamper.
Build Gravel Base
- Pour a generous amount of crushed gravel paver base into the hole so your finished base will be approximately five-inches thick.
- Wet the gravel thoroughly with a garden hose, and then use the hand tamper to compact it into a hard layer a couple of inches below the surface.
- Check the base at several points to be sure it is level and make adjustments where necessary.
Lay out the Fire Pit
- Place the blocks one-by-one around the perimeter of the hole, pushing them together and using a level to make sure the height stays consistent.
- If necessary, add leveling sand beneath low blocks or tap high blocks down with a rubber mallet to keep everything even.
- After finishing the first row, check the layer in several places with a long level to be sure the structure is even.
- Then, temporarily assemble the second level of blocks, making sure to stagger the joints between rows.
Test Fit the Bowl or Insert
Bowls and insert rings come in several standard sizes, so make sure to choose the right one for the fire pit you’re planning to build.
Add Construction Adhesive to the Blocks
Use construction adhesive between the layers of blocks to secure the concrete block pavers as you build the fire pit walls.
- Remove the second row of blocks that were temporarily placed.
- Add beads of construction adhesive to the bottom layer to bond everything in place.
- Refit the second layer of blocks and continue the process for the third row of blocks.
A fire pit typically has three or four rows of blocks. Repeat the test-fitting for each layer before securing with adhesive.
Tips courtesy of homedepot.com