Making a wood fire in your barbecue pit instead of using charcoal takes a bit more time, but with patience and the right tools it can easily be done. How you build the fire depends somewhat on the style barbecue pit you have, but the general fire-building rules are the same. A wood fire provides a longer, slower cooking process that produces juicy, tender meats and vegetables with a distinct smoky flavour.
Remove any grates or grills covering the top of the barbecue pit. If your pit has a door to the fire pit and the grill surface to one side, open the doors.
Make a pile of small kindling in the centre of the pit. Shredded paper, cardboard, wood shavings, and dry grass all work well for kindling. The bigger the pile of kindling, the better: the longer the kindling burns, the more time it has to catch the twigs on fire.
Over the pile of kindling, arrange small sticks and twigs in a tepee shape. The idea is for the kindling to catch the small sticks on fire, which will burn longer than the kindling, and then transfer heat to the logs.
Squirt some liquid or gel lighter fluid on your bigger logs before placing them in the pit. Put on enough lighter fluid that the logs catch in various places, but don't saturate the wood.
Arrange wood pieces around the small sticks, again in the tepee shape. You can also lay the logs flatter; just make sure they touch the smaller tepee without squashing it. Anything from dried tree branches to standard fireplace logs, or even scrap wood from building projects, works for your major wood pieces. Place the wood on the stack gently so you don't collapse the previous layers.
Wearing a heat-safe glove, carefully light the kindling with a barbecue lighter, or light the end of a stick on fire and hold it to the kindling until it catches. Light several spots in the kindling to get the fire going faster. Do not to ignite the lighter fluid on the logs; the flames will shoot up and burn you with little warning.
Blow gently on the kindling to reignite the embers. A bellows can also be used to do this. Allow the kindling to burn, giving it enough time to heat and catch the twigs. If your kindling burns up too quickly, carefully add more, wearing the heat-safe glove.
Allow the twigs to catch fire, then carry the flame up to the logs. The lighter fluid on the logs should increase the fire's intensity enough that the logs eventually catch fire. You can strategically add more lighter fluid to the logs to help them catch. However, simply dousing the logs with lighter fluid indiscriminately only wastes fluid, as it burns off quickly without properly igniting the logs.
Once the fire is burning steadily, the logs have caught, and parts of them are glowing red, you can replace the barbecue grill top, if you plan to cook over the flame; leave it open if you want to toast marshmallows or simply warm your hands while you're outside. If your fire pit has a door, shut the door and open the grill top, which should be receiving heat by this point.
Add a log to the fire about once every hour. Do not smother the embers in the fire's centre when you add new logs.
When cooking over a wood flame, rotate food around the grill top to achieve even heating. Cooking over a wood fire takes longer than with charcoal or gas, but your patience will pay off with tender and juicy meats and vegetables. Only use dry wood, twigs, and paper. Wet kindling or wood produces excessive smoke. Have an ash base in the bottom of the pit before you start. If there is no ash, pour in some sand, just enough to cover the bottom of the pit to a 1/2-inch depth. Wood ash is great for composting, so after your fire burns out, save the wood ash for another use.
Always practice proper fire safety precautions when working around an open flame. Juices and fat from food dripping into the fire can cause flare-ups, so keep your distance while cooking, especially during flipping. Never use printed paper or other kindling containing dyes, coatings, plastics, or anything containing chemicals, as when these burn off they can contaminate your food. If using printed or coated paper, allow the kindling to burn off before using the flame to cook food.