The only legal measurement for the sale of firewood is the CORD.
It is defined as: " a loosely stacked pile of split firewood measuring 4 feet high by 8 feet long by 4 feet wide." Overall the cubic volume is 128 cubic feet. This is calculated by multiplying the length x width x height.
Although the cord is a defined measurement it is open to interpretation. This can make it difficult to estimate the volume of firewood, especially if it is unstacked.
Here are a few things to remember:
- the length of logs vary
- the diameter of logs will affect the stacking
- loose wood is 30% to 40% more volume
- wet wood can take up to 15% more volume
- 2 x 4 x 16 is also a cord
The Perfect Log Would be 14 Inches Long
The length of the logs will vary with most firewood. If they were a uniform 14" then a loose stack of three rows would equal 4 feet (with spacing). This is rare. Most wood varies and if it is more than 16" your cord will be two rows wide. The seller should make up for this by adding length and height to the cord, but in many cases they will just loosely space the two rows to equal approximately 4 feet in width. Technically a cord that is two logs wide should have 22" logs to equal 4 feet (with space in between). If that were true the logs would be too large for most fireplaces and stoves.
Not All Logs are the Same in Diameter
The diameter of the logs will also affect the stacking. Smaller diameter logs can be stacked more tightly, while large diameter logs will stack looser. A good mix of each will insure a truly measured cord, while too much of either size will vary the results.
A Pile is Much Less Than a Stack
A random PILE of firewood that is 4 feet x 8 feet x 4 feet does not equal a STACK of the same dimensions. Unstacked firewood takes 30% to 40% more room than the same wood stacked. A round pile can be very deceiving compared to a uniform stack. Stacking is the only true way to measure, otherwise you're counting air instead of firewood.
Wet Wood is Larger Than Dry Wood
Most people do not realize wet wood takes up more room than dry wood. It's just common sense. When the water evaporates, the wood shrinks. In some species this can be as much as 15%. If you don't believe it than just look at building lumber. Does anyone use wet lumber? No, because it shrinks when it dries. If you buy a wet cord you will have less than the same measured dry cord.
128 Cubic Feet Has a Lot of Possibilities
The defined cord is 4 feet x 8 feet x 4 feet. The magic number here is the 128 you get by multiplying the three measurements. The following also equal a cord:
2 x 4 x 16
2 x 8 x 8
1 x 4 x 32
1 x 1 x 128
Get the idea ?!
Still Not Sure What a Cord is?
If you're still confused about the size of a cord of firewood, you're not alone. Many sellers don't know either. There's a lot of room for error when you consider the average hardwood firewood cord weighs over 2 tons and contains 800 to 1000 pieces. Stacking it takes a lot of time but is the only true way to measure a cord. Be sure you have your firewood stacked unless you've got a really good eye. Most times cord deliveries aren't over, they're under.
