Building Wood Fires (Countryman Press, 2018), explores different fireplaces to keep your house warm in the winter. McGivney shares recipes meant to be cooked over an open flame. Use the step-by-step instruction to build your own fire pit and cook the recipes in your own backyard. Find this excerpt in Chapter 4, “Backyard Fires.”
Wood Burning Fire Pits
For all the same reasons that a fire is one of the most beloved parts of a camping trip and a crackling fire in a fireplace adds ambiance to an indoor living room, a real wood burning fire pit in the backyard is hard to beat (as long as it is legal). Compared to natural gas or propane, a wood burning fire has the ability to give off a more intense heat. Firewood is readily available and offers aesthetically pleasing aromas. Plus you can cook on the fire and the coals. And as my son and his friends discovered, there is something pleasingly primal about sitting around dancing flames generated by a technology that has been used by humans for more than a million years.
Portable wood burning fire pits are basically large metal bowls that range in diameter from about 30- 36 inches and are about 20- 28 inches deep. Most have legs to keep the container a few inches above the ground and all have tight fitting spark arrestor screens to prevent flying embers. The bowls are made from stainless steel (which is the least expensive), cast iron, or copper. Cast iron is durable and has the added benefit of radiating heat from the bowl’s surface. Deeper iron bowls often have cut- out designs on the walls that add interest and allow viewing the fire from the side as well as the top. However, iron is prone to rusting and needs to be covered when not in use to protect against moisture. Copper is visually appealing and can add an aesthetic element to backyard landscaping but it is also significantly more expensive. Copper does not rust and it gains a pleasing patina over time. No matter what they are made of, portable fire pits should be placed on concrete or stone and never on wood decks.
The main advantage to a portable fire pit, besides the fact that it is portable, is the tight- fitting spark- arresting screen and the ease of cleaning. The bowl can just be picked up and the cold ashes dumped into the garden or trash. But these pits are generally smaller than permanent fire features and they are not integrated into the backyard space the way a permanent fire pit is.
Building a fire pit in the backyard can be as simple as following these steps:
Step 1: Find a level patch of ground that is at least 12 feet in diameter. Drive a stake in the ground that is attached to a string 2– 3 feet long. Rotate the string to form a perfect circle and mark the perimeter with spray paint. Remove dirt from the circle, reaching a depth of about 18– 20 inches deep.
Step 2: Shovel 6 inches of fine gravel into the pit and rake it smooth. Tamp down the gravel to create a solid base. Then spread a layer of coarse sand that is 1– 2 inches thick. Tamp it down and make sure the surface is level.
Step 3: Cut a strip of sheet metal to match the depth and circumference of the pit. Wrap the metal around the inside of the pit, covering exposed dirt. Use iron stakes to secure the metal flush against dirt wall.
Step 4: Place concrete retaining wall blocks around the rim of the pit. Use a rubber mallet to pound blocks into place and make sure they are flush with one another. Lay a second layer of blocks that is staggered over the first layer. Attach the two tiers of blocks using masonry adhesive. Allow slight gaps in the blocks to encourage airflow to the fire. Allow two days for the adhesive to dry before you use the pit.
Alternative Fuel Fires: Natural gas and propane
Unlike wood- burning fire pits, backyard fire features that are fueled by natural gas or propane are widely allowed across the United States because they do not contribute to particulate air pollution or emit embers that can start wildfires. However, some extremely dry cities in the West that are especially vulnerable to wildfire require that natural gas or propane burners be registered. Rather than have fake wood, most of these pits are filled with lava rock that covers a circular gas burner. Some fire pits are filled with colorful glass or specially heat- treated river rocks. It is important to only use fire pit materials that have been provided by the manufacturer and are designed to withstand extreme heat. Untreated river rocks or stone may explode and cause serious injury to those sitting around the fire pit.
If you are contemplating upgrading the landscaping in your backyard, a stationary natural gas fire pit can be incorporated into the design project. The pit will need to hook into a natural gas line and be located in a place that follows local building codes. When constructing a patio with a gas fire pit, it is also convenient to use the same line for hooking up a gas barbecue grill as part of the outdoor room. Before any construction begins be sure to have all utility lines marked on your property. Most regions in the United States are part of the North American One Call Referral System (888- 258- 0808), which will contact all the utilities in your area to have the lines in your yard marked. The network generally requests at least three days’ notice before you plan to begin excavation.
Propane fire pits are usually mobile and hook up to a propane tank that is not far from the pit. Often the pit is incorporated into a table that offers a place to prop feet and also hides the tank. Compared to natural gas, the mobility of the propane- fired pit offers more flexibility for backyard uses and can also be an easy back- up for times of year when wood burning fires are banned. The drawbacks are that the fire is generally smaller than a natural gas pit and the tank can run out at inopportune times.
Even though natural gas and propane fire pits do not generate embers, they still emit steady heat that travels up in a column. In order to provide proper venting, they should be situated under the open sky without tree branches overhead and should also be at least 10 feet away from any structures. A valve and/or push- button ignition makes these fire pits easy to start and instantaneous flames can be adjusted by regulating the gas flow. There is also no mess of ashes to clean up when the party is over.
Eco- friendly fuels
Bioethanol is the latest innovation in clean burning fire technology. Portable fire pits using bioethanol are completely free standing and are allowed throughout the United States just like natural gas and propane units, but these come with a smaller carbon footprint than fossil fuels. Bioethanol is a clear, odorless liquid produced from fermented plant material, such as sugar cane, corn, and wheat. Currently, most bioethanol fire pits utilizing this new and evolving technology have fake ceramic logs that are fed by a liquid fuel canister attached to the fire bowl. A one- liter canister burns for approximately two hours.
Logs made from alternative materials such as coffee grounds, grass, and soy also offer environmentally sustainable options for a backyard fire pit. Yet, even though these innovative “logs” are not made from wood, they are still restricted in places where wood burning fires are banned. The Pine Mountain Java- log is made from recycled coffee grounds and burns for four hours. Unfortunately, it does not smell like coffee when it burns but it does give off BTUs comparable to wood. Pine Mountain, the company that produces the Java- log, has established agreements with large coffee shop chains to pick up their discarded coffee grounds and turn the garbage into fuel. Coffee grounds contain more oil than wood, which makes it easy to burn, even though it has less carbon than trees. According to OMNI, an independent testing company, the Java- log burns seven times cleaner than wood and emits 96 percent less residue into the air. It comes in a paper wrapper that can be put in the fire pit and, once the paper is lit, the log easily catches fire.
Try This: Turn an Old Washing Machine Drum into a Fire Pit
If you’re feeling handy or just like the ethics of up- cycling, head to a junkyard to find your fire pit. Your quarry is the drum from any top loading washing machine. The size, shape, and sturdy stainless steel construction with its many tiny holes make the inner drum a perfect portable fire pit.
• Extract the drum from the body of the machine.
• Remove the plastic rim around the drum and all other non- metal pieces.
• Use an angle grinder to cut out the drum’s center spindle.
• Use the grinder to cut off the metal lip on the top of the drum and then smooth the surface and polish away any soap scum. (This is for cosmetic, not functional, reasons.)
• You can choose to make legs for the drum with metal pipe or by cutting legs off an old metal bed frame and welding them to the bottom. Or you can go without legs and place the drum on a foundation of firebricks (regular clay bricks or other stone could dangerously explode under the fire’s heat).
• Paint your drum a fun color with high temperature paint, and you are done.