What is a Cord?
Firewood quantities are sometimes difficult to estimate. The official measurement of firewood is a cord. To help you make an accurate estimate, here is how some common units of firewood measurements compare to a full cord.
A full cord is a large amount of wood. It measures four feet high by four feet wide by eight feet long (4‘x 4‘x 8‘) and has a volume of 128 cubic feet.
A face cord or rick of wood is four feet by eight feet long and is wide as the individual firewood pieces, but averages 16 inches wide. A 16-inch wide face cord is equal to one-third of a full cord.
One plus one-third full-size pick-up truck load (eight foot box) equals one full cord. If the wood is stacked neatly, the wood will be about level with the truck box sides. If it’s thrown loosely into the truck box, the wood will be about as high as the truck cab.
Some Facts about Firewood
Firewood is an area where you can have great influence over how well your system performs and how enjoyable your experience will be. Quality, well-seasoned firewood will help your wood stove or fireplace burn cleaner and more efficiently, while green or wet wood can cause smoking problems, odor problems, rapid creosote buildup and possibly even dangerous chimney fires.
A few minutes spent; understanding firewood will be time well spent, so please read on for general background information, as well as how to buy wood and store wood.
The heat produced by burning firewood is actually the energy of the sun, the ultimate source of all energy on planet earth. Through the process of photosynthesis, arguably the single most important thing that happens on our planet, trees are able to store solar energy as chemical energy that we can use for heat when the sun abandons us to the cold dark days of winter. Burning wood is just the quick reversal of this process, liberating the suns heat when we need it most.
Unlike the burning of fossil fuels like gas or oil, which many believe to be upsetting our climate for the worst. Burning firewood releases no more harmful greenhouse gases than would be produced were the wood to simply rot on the forest floor. If we are responsible in the ways we select, cut, and burn our firewood, wood burning can actually be the correct choice for the environment too.
All firewood contains water. Freshly cut wood can be up to 45% water, while well-seasoned firewood generally has a 20-25% moister content. Well-seasoned firewood is easier to start, produces more heat, and burns cleaner. The important thing to remember is that the water must be gone before the wood will burn. If your wood is cut six months to a year in advance and properly stored, the sun and wind will do the job for free. If you try to burn green wood, the heat produced by combustion must dry the wood before it will burn using up a large percentage of the available energy in the process. This results in less heat delivered to your home, and literally gallons of acidic water in the form of creosote deposited in your chimney.
Wood is composed of bundles of microscopic tubes that were used to transport water from the roots of the tree to the leaves. These tubes will stay full of water for years even after a tree is dead. This is why it is so important to have your firewood cut to length for six months or more before you burn it, it gives this water a chance to evaporate since the tube ends are finally open and the water only has to migrate a foot or two to escape. Splitting the wood helps too by exposing more surface area to the sun and wind, but cutting the wood to shorter lengths is of primary importance.
There are a few things you can look for to see if the wood you intend to purchase is seasoned or not. Well-seasoned firewood generally has darkened ends with cracks or splits visible, it is relatively lightweight and makes a clear clunk when two pieces are hit together.
Green wood, on the other hand, is very heavy. The ends look fresher, and it tends to make a dull thud when struck. These clues can fool you however, and by far the best way to be sure you have good wood when you need it is to buy your wood the spring before you intend to burn it and store it properly.
Even well-seasoned firewood can be ruined by bad storage. Exposed to constant rain or covered in snow, wood will reabsorb large amounts of water, making it unfit to burn and causing it to rot before it can be used. Wood should be stored off the ground if possible and protected from excess moisture when weather threatens.
The ideal situation is a wood shed, where there is a roof but open or loose sides for plenty of air circulation to promote drying. Next best would be to keep the woodpile in a sunny location and cover it on rainy or snowy days, being sure to remove the covering during fair weather to allow air movement and to avoid trapping ground moisture under the covering. Also don’t forget that your woodpile also looks like heaven to termites, so it’s best to only keep a week or so worth of wood near the house in easy reach. With proper storage you can turn even the greenest wood into great firewood in six months or a year, and it can be expected to last three or four years if necessary.
Firewood is generally sold by volume, the most common measure being the cord. Other terms often employed are face cord, rick, or often just a truckload. A standard cord of firewood is 128 cubic feet of wood, generally measured as a pile 8 feet long by 4 feet tall by 4 feet deep. A face cord is also 8 feet long by 4 feet tall, but it is only as deep as the wood is cut, so a face cord of 16 wood actually is only 1/3 of a cord, 24 wood yields ½ of a cord, and so on.
Webster defines a rick simply as a pile, and truck sizes obviously vary tremendously, so it is very important that you get all of this straight with the seller before agreeing on a price; there is much room for misunderstanding. It is best to have your wood storage area set up in standard four or eight foot increments, pay the wood seller the extra few dollars often charged to stack the wood, and warn him before he arrives that you will cheerfully pay only when the wood actually measures up to an agreed upon amount.
Another thought concerning getting what you pay for is that although firewood is usually sold by volume, heat production is dependent on weight. Pound for pound, all wood has approximately the same BTU content, but a cord of seasoned hardwood weighs about twice as much as the same volume of softwood, and consequently contains almost twice as much potential heat. If the wood you are buying is not all hardwood, consider offering a little less in payment.
A Few Random Details
Yes, it’s OK to burn a little pine, even construction scraps as long as you burn just a little and use it mainly for kindling.
DO NOT, however, burn large quantities of resinous softwoods as these fires can quickly get out of hand.
DO NOT burn any construction scraps of treated or painted wood, especially treated wood from decks or landscaping ties. The chemicals used can release dangerous amounts of arsenic and other very toxic compounds into your house.
If the seasoned wood you bought turned out to be pretty green and you elected to try to burn it anyway, be sure to have the chimney checked more often than usual, you may build up creosote very quickly. You don’t have to burn only premium hardwoods. Less dense woods like elm and even soft maple are abundant and make fine firewood as long as you ‘re willing to make a few extra trips to the woodpile.
Many people also have questions about burning artificial logs. Convenience is their strong suit and in general they are fine when your time is an issue and you want a quick fire without all the muss and fuss of natural firewood. Usually they should be burned only one at a time and only in an open fireplace. One should be careful about poking them and moving them around once they are burning since they may break up and the fire may get a bit out of control. Be sure to carefully read the directions on the package.
Thanks for your time and attention. We hope you have all your firewood questions answered. If not, check the general Questions & Answers area, and feel free to e-mail us from there if you still need help.
Characteristics of Firewood
Some types of wood are more user-friendly since they ‘re easier to start on fire and will burn much better. Ash is often called the Firewood of Kings since it burns well even when freshly cut.
Generally speaking, woods high in resin content (pine, spruce, fir) aren’t used in the home fireplace since resin build-up in a chimney can promote chimney fires.
Woods that pop and spark are also considered less desirable for burning. No matter what type of wood is burned, it’s important to practice good maintenance by having a chimney periodically inspected and swept.
Rating the overall quality of firewood is open to some debate, but the categories below should give the reader a rough idea of where the various woods stand.
Overall Rating Type of Firewood
Excellent=Ash, Beech, Hickory, Sugar Maple, and Oak
Good= Black Cherry, Black Locust, Red Maple, and Black Walnut
Fair= Elm, Sweet Gum, Poplar, and White Pine
Source: The Chimney Safety Institute of America