How to Build a Firepit Out of Cinder Blocks
- 1). Select a style. Depending on what you want out of your fire pit, you may choose one of various sizes and types: round, square, rectangular or free form. If you will be grilling in the pit, be sure to plan the dimensions of your pit based around the shape and size of your grill grate.
- 2). Dig within the boundaries of your site to a depth of between six and 10 inches. Once you've made a level excavation, lay two inches of gravel and then two inches of concrete. Level the concrete with a trowel and allow to dry.
- 3). Place your bottom levels of cinder blocks according to your fire pit design. Use mortar between each block and each layer, including the first, and stagger layers by placing subsequent layers between previous ones. This will enhance the fire pit's strength and durability. Usual height for a fire pit is between two and a half to three feet tall, so usually two levels will suffice before adding your rebar and final layer.
- 4). Lay three or four pieces of rebar, spaced evenly across the pit. This is where your grill grate will rest on. Next, place the final layer of cinder blocks, using extra mortar to keep it level in spite of the rebar.
- 5). Place one-inch-thick cap pieces (stone slabs) over the tops of your cinder block fire pit's perimeter. Spread mortar beneath them to attach them to the pit and be sure to cover the entire top surface of cinder blocks.
- 6). Allow 48 hours for the concrete and mortar to dry. Light your fire in the bottom of the pit, place the grill grate on the rebar and enjoy grilling.
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