How to Build a Brick or Rock Fire Pit
- 1). Drive a wooden stake into the ground at each corner of the location of the fire pit.
- 2). Dig a square hole 8 to 10 inches deep inside the stakes.
- 3). Put a 2- to 3-inch layer of gravel in the hole. Rake the gravel level and tamp it down.
- 4). Mix a batch of mortar, following the instructions on the packaging. Pour a 2-inch layer of mortar over the gravel. Smooth the surface with a trowel and allow the mortar to set for three or four days.
- 5). Add a layer of fresh mortar around the perimeter of the fire pit. Lay firebricks on top of the mortar, keeping them about 3/8 inch apart. Fill the gaps between the firebricks with mortar. If necessary, cut the firebricks with a wet saw to fit.
- 6). Add mortar on top of the firebricks, then install another row of firebricks. Stand the bricks in the second row on their ends, keeping them 3/8 inch apart and filling the gaps with mortar.
- 7). Begin laying the bricks or rocks on the outside of the firebricks, filling the gaps with mortar.
- 8). Continue to build the outer walls of the fire pit until you are 4 to 6 inches above the top of the firebricks. Stagger the bricks or rocks in each row from the previous row to strengthen the walls.
- 9). Add mortar on top of the last layer of bricks or rocks and set the capstones into position. Allow the mortar to set for three or four days.
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