Introduction to firewood
A Forno Bravo wood fired oven is considered a “black oven” which means the firewood you use is in the oven chamber where your food is cooked. You want to avoid using anything that will release hazardous chemicals into your food, make it hard to keep your temperature consistent or leave a soot and creosote buildup that presents a fire hazard.
What not to use as firewood
Never burn laminated woods like plywood (or particle board), pressure treated woods or anything painted or chemically treated or glued. You can use untreated pallets and construction lumber scrap for kindling to get your firewood going. If you aren’t sure if the wood has been treated chemically: “when in doubt, throw it out.” You don’t want these toxins in the air or in your food.
Charcoal shouldn’t be used in your home pizza oven. One reason not to use charcoal is because it produces more carbon monoxide than firewood. Since carbon monoxide is undetectable without equipment it is a safety issue. Also, despite charcoal burning hotter than firewood, it doesn’t transfer that heat as efficiently inside the oven. Brick ovens get heat in three ways, flame refraction off the dome, thermal equilibrium and hot coal transfer. Because charcoal doesn’t produce a direct flame, you lose one of the sources of heat in a brick oven. Using charcoal in your Forno Bravo oven can void the warranty and present safety risks.
Avoid resinous woods with high sap or oil contents like red pine. This type of firewood will leave excessive soot coating the pizza oven and chimney flue with creosote. You can burn it off with a hotter / clean burning firewood like oak. While you can handle most routine oven cleaning, it’s a good idea to hire a certified chimney sweep at least once or twice yearly (more often depending on frequency of use). Some woods that fit into the sappy or oily category are most pine, fir, eucalyptus, white birch and cedar. However, if you decide to use some oily woods for flavor remove the resinous bark to reduce moisture and sap content.
Best woods to use for woodfuel
The best woods to burn in your Forno Bravo pizza oven are hardwoods such as oak, maple, ash, beech, and birch. Oak is probably the safest, easy to find and it burns very hot compared to other woods. Hardwoods also weigh as much as three times as softwoods so they give off more heat (BTU’s).
Fruitwoods are also extremely popular including apple, almond, cherry, hickory, pear and pecan. Another advantage to fruitwoods are the fragrance. Some of the best-known wood fired pizzerias swear by apple because it burns very hot, has a great aroma and flavor.
If you choose to use a softwood, ensure you properly cure and season it to reduce sap content. Also, removing the bark from the top will also help reduce moisture and sap content.
Woodchips and wood pellets can be used as kindling and fuel provided they fit the untreated conditions set forth above. However, they will typically not produce the same amount of BTU’s as firewood, so it probably won’t work as the sole woodfuel source in your pizza oven.
The type of wood you burn will depend on where you live. There are some great resources about firewood on university and state sponsored websites.
Moisture levels in firewood are critical
Firewood should have a moisture content around 20%. A moisture content lower than 15% is actually too dry for use in wood fired ovens. Overly dry wood will convert heat energy to smoke and creosote on a bed of hot coals. A good way to check is to see if the firewood has darkened cut ends with small radial cracks, this means the wood is very dry.
Wet or damp wood will burn poorly and also produce a lot of smoke. If your wood is green, it is most likely uncured, will burn poorly and produce a lot of smoke. This will cause soot and creosote build up and not burn very hot.
Harvest or buy firewood in early spring or late winter if possible so it has the summer to dry out.
We suggest you invest in a wood moisture gauge if you can’t find a reliable source or harvest your own wood.
Burning or cutting firewood
If you have sufficient storage room, try to purchase wood a cord at a time. A cord is a stack of wood four feet wide, four feet high and eight feet long (4’x4’x8’). Be careful, as many people have been ripped off by un-reputable foresters looking to make a quick buck. For a complete understanding of what a cord of wood is, click here.
If you cut your own firewood, try to do it in the off-season, when the sap is in the roots. Wood should be given about six months to a year to dry properly. You will know it’s ready when the cut ends have darkened and a series of “checks’ or cracks have appeared across the ends.
Split wood dries faster than rounds, catches fire faster and burns brighter in the oven. As a general rule, the wood you burn should be no larger than 3″ in diameter and around 12-18 inches long. Kindling is cut into smaller pieces. Do not use bark, needled pine twigs, or leaves for kindling; they are too resinous and smoky. If you do leave the bark on because you want more smoke, than we suggest you turn the bark up with the exposed wood below, this will help it catch fire and burn better in the oven.
If you are stuck with a load of damp wood, or your wood has been rained on, there is one trick to help dry it out. Each time you are finished cooking with your oven, place the next day’s wood inside the oven. Doing this will bake out the moisture using the previous fire’s retained heat. Even if you are doing low heat cooking overnight, you can still dry your next load of wood the next day. It really works. Be sure to leave the oven door open slightly to let any gasses escape from the oven chamber.
Storing and managing firewood
We recommend you build your foundation 2” to 3” above ground to prevent rain from getting the firewood stored under your pizza oven wet. You can store some wood below your oven, but the size is somewhat restricted, and it might be best reserved for kindling and your wood supply for the next few firings. If you purchase a Forno Bravo Cucina stand, it provides wood storage below the pizza oven hearth.
If you have room, build a woodshed to store your split wood. An effective woodshed has a waterproof roof and a raised floor with gaps for sufficient airflow. If your wood should be rained on or otherwise dampened, you can place it in your oven with the door slightly ajar after you are finished cooking and it should be sufficiently dry for use the following day.
As always, another great resource is the Forno Bravo community Forum, with over 26,000 users worldwide with brick ovens, why not ask someone who has already done the research in your area?