Building an outdoor fire pit is an easy and rewarding project anyone can accomplish with the right safety precautions and materials. Following a few guidelines will result in a unique outdoor fireplace in your yard. Here are some tips for building a sturdy, safe, and long-lasting outdoor fire pit.
1. Dig and Lay a Good Foundation
Your outdoor fire pit should ideally rest in a trench area laid with rock, away from any structures or shrubbery that could potentially present a fire danger. A good rule of thumb is to place your fire pit at least 10 to 30 feet away from any structure. It is recommended to check your local fire codes concerning outdoor burning. These can vary from place to place, and some towns require additional insurance and/or permits before building a fire pit.
Dig a circular trench in softer dirt for your fire pit foundation, and fill this with good quality concrete from a cement mix that contains portland cement and sand. This will give the fire pit the durability and strength it needs. Mix the concrete with less water for a thicker consistency; this will prevent cracking later. You should dig your circular trench roughly as deep as your rocks or bricks are long, and level the poured concrete with a trowel to make it as even as possible.
2. Provide a Simple Drainage Sump
In the center bottom of your fire pit, dig a hole roughly the diameter of a fence post and fill this with dry gravel or sand. This will help rainwater drain away from your fire pit, prolong its use, and prevent later water damage.
3. Select the Right Rocks
The best stones for an outdoor fire pit are large, flat ones. Lay the first set of them around the outer perimeter of the pit; this will give off the impression of them being stacked. Other options include river rock, landscaping blocks, or even bricks for this step. Be sure to use a generous amount of cement on the outside bottom of each rock to secure it in place within your fire pit foundation.
Stack the rest of the stones with cement in a circular structure, similar to the idea of laying brick. However, only apply cement to the outer area of each stone to protect from the heat. Also fill in any gaps in the rock with additional concrete; this will prevent any flames from escaping through the sides of the finished structure. It is not recommended to use home-fired clay bricks or porous rocks; these can potentially explode when heated past a certain temperature.
4. Fire Safety
Before lighting your fire pit, pour a circle of water around its outer perimeter to prevent stray fires. It is also a good idea to keep at least one five-gallon bucket of water on hand just in case. Some cities outlaw fire pits but allow barbecue pits; if this is the case, purchase a grate big enough to keep over the top of your fire pit to stay within this ordinance.