How much wood in a cord?

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That would work out to 192ft.
So here are the figures that I used to make my "Guesstimate" based on the dimensions of the box on my trailer that is = to 132 Cu.Ft. (Volume = L x W x H) Trailer Box is 12' x 6' x 22". Because one of the dimensions is inches I convert all dimensions to inches.
144 x 72 x 22 / 1728 = 132.
To make this a little easier I took the Avg. diameters of 12" and 16" and used 14" so all rounds are theoretically 14" wide x 16" long
A Length of 144" = 9 rounds @ 16"
A Width of 72" = 5 rounds @ 14"
A Hight of 22" = 2 @ 14" (28")
+ 30% = 27 rounds (to fill voids. Because rounds do not stack as tightly as split wood.)
And finally I added another 30% (27 rounds) for the actual rounds that will vary in diameter.
Total = 144 rounds
 
Diameter is the key here
It’s all measure of volume. A full cord is 128 cubic feet (4 x 8 x 4).

Since we’re dealing with inches (diameter), we first convert cord cubic feet to inches (48 x 96 x 48) = 221,184

Can also simply multiply total cubic feet by 12^3 to convert to inches:
128 x 1,728 = 221,184

Second, using the average diameter of log size suggested by the op (14”), we find the area of a circle (cross-sectional area of the log) using area formula:
π * r2

We do this by multiplying π (3.14) by the radius squared:
7 x 7 = 49
3.14 x 49 = 153.86

Last, to determine the total linear length of the log, we divide the cubic inches in a cord by the area of the circle in the last step, then convert inches back to feet:

221,184 / 153.86
= 1,437.56”

Convert back to feet:
1,437.56” / 12
= 119.79 feet

Total linear feet of 14” diameter log equal to a full cord is: 119.79’
 
It’s all measure of volume. A full cord is 128 cubic feet (4 x 8 x 4).

Since we’re dealing with inches (diameter), we first convert cord cubic feet to inches (48 x 96 x 48) = 221,184

Can also simply multiply total cubic feet by 12^3 to convert to inches:
128 x 1,728 = 221,184

Second, using the average diameter of log size suggested by the op (14”), we find the area of a circle (cross-sectional area of the log) using area formula:
π * r2

We do this by multiplying π (3.14) by the radius squared:
7 x 7 = 49
3.14 x 49 = 153.86

Last, to determine the total linear length of the log, we divide the cubic inches in a cord by the area of the circle in the last step, then convert inches back to feet:

221,184 / 153.86
= 1,437.56”

Convert back to feet:
1,437.56” / 12
= 119.79 feet

Total linear feet of 14” diameter log equal to a full cord is: 119.79’
So all that rocket science gets you pretty close to my "guess of 128' if using 12" rounds?
I may not be a scientist, but I did stay at a holiday inn one time. I've also put a cord of wood in my trailers once or twice :laugh: .
Screen Shot 2022-02-21 at 10.12.06 PM.png
 
It’s all measure of volume. A full cord is 128 cubic feet (4 x 8 x 4).

Since we’re dealing with inches (diameter), we first convert cord cubic feet to inches (48 x 96 x 48) = 221,184

Can also simply multiply total cubic feet by 12^3 to convert to inches:
128 x 1,728 = 221,184

Second, using the average diameter of log size suggested by the op (14”), we find the area of a circle (cross-sectional area of the log) using area formula:
π * r2

We do this by multiplying π (3.14) by the radius squared:
7 x 7 = 49
3.14 x 49 = 153.86

Last, to determine the total linear length of the log, we divide the cubic inches in a cord by the area of the circle in the last step, then convert inches back to feet:

221,184 / 153.86
= 1,437.56”

Convert back to feet:
1,437.56” / 12
= 119.79 feet

Total linear feet of 14” diameter log equal to a full cord is: 119.79’
No void space for all those 14" rounds?
 
A 16" round , 12" long is 1.5 cubic ft.... If it is 16" long you need to multiply 1.33 to the 1.5 cu ft.. SO, 12.5 X1.33 is 1.995 cu. ft. We will go with 1.75 cu ft. cause the bark will fall off. You will need 73 logs 16" long and 16" in diameter to make a cord. 128 cu. ft in a cord . 128 divided by 1.75 comes to 73. . That would be a perfectly tight fit however. I am sure with the air space you can knock off 10% and that would be 66 logs. That seems about right. If I am wrong, let me know, I would like to know myself.
 
Years ago... I came up with a system of measuring. Worked pretty well, and kept things fairly accurate.
I had a problem with yard monkeys... They would "cut a lot of wood". How much? We don't know... but you owe us a "lot of money". It always seemed that there was less wood than the money going out.
So, what to do?
Measure the length of the logs. Measure the circumference. Since we are not making boards, board feet didn't really work.
actual cubic feet did. Logs tend to taper at a constant rate, so measuring the middle worked...
work the thing up as a cylinder. pi r squared... times length

I could deck the logs, measure them, and say there is this much cubic feet in that deck.

Origional question...
how much wood in a "cord". 7 years later, I have done this hundreds of times. Depending on the size of the splits, 16" wood works out to 95 to 105 cubic foot.
 
So all that rocket science gets you pretty close to my "guess of 128' if using 12" rounds?
I may not be a scientist, but I did stay at a holiday inn one time. I've also put a cord of wood in my trailers once or twice :laugh: .
View attachment 967097
Only once or twice? Ha. I know you’ve been around long enough that it’s probably more like once or twice every other day
;-)

No void space for all those 14" rounds?
Voids created by rounds aren’t a factor here.

Since the OP wanted to know how long a single log of a certain diameter would need to be to equal one cord of wood, this equation eliminates the voids and simply converts the shape of the cord to a single solid round log.

The result will be the exact same amount of wood (one full-solid cord) every time…The same as if you took a solid block of wood the size of a cord and cut it up into firewood.

12” dia x 163 ft
= 128 cubic feet

14” dia x 119.8 ft
= 128 cubic feet

16” dia x 91.7 ft
= 128 cubic feet

54” dia x 8 ft
= 128 cubic feet

Cut the 12” log above into 16” long pieces and you end up with 122 rounds; which after chopping would equal exactly one full (solid) cord.

You’d still be hard pressed to actually get all of the pieces to fit exactly into a 4x8x4 space, since even the most nicely stacked cord has some air gaps between pieces, which we are all aware of and the reason many folks add a little extra to their product (kind of like a baker’s dozen).

Your specific method of splitting and stacking will affect the final dimensions of the cord stack.

I’ve shared this with numerous folks around here who have relied on many other methods of estimating and some were surprised at how much it helped them more accurately estimate their product before and after processing.

For those on here who regularly cut wood, give it a test and you might be surprised how accurate it is.
 
Patrick72 said it well above.

No stack is going to be completely solid.

Therefore, although a full cord is 128 cubic feet, there isn’t going to actually be that much wood in the stack unless the provider intentionally adds it as a bonus.

Being able to calculate a full cord equivalent before processing and evaluating how it stacks out using your particular processing method can help the provider more accurately determine the typical percentage of their cords that is air and help increase the accuracy of their product, price and profit.
 
In my experience, ten 16' logs averaging a foot in diameter will turn into a stacked cord more or less. No tape measure required, but I do need to take my mitts off.

Or - if you have a tree service friend - ONE 16' log ~3' in diameter will do it too.
 
A 16" round , 12" long is 1.5 cubic ft.... If it is 16" long you need to multiply 1.33 to the 1.5 cu ft.. SO, 12.5 X1.33 is 1.995 cu. ft. We will go with 1.75 cu ft. cause the bark will fall off. You will need 73 logs 16" long and 16" in diameter to make a cord. 128 cu. ft in a cord . 128 divided by 1.75 comes to 73. . That would be a perfectly tight fit however. I am sure with the air space you can knock off 10% and that would be 66 logs. That seems about right. If I am wrong, let me know, I would like to know myself.
I agree with using 10% as a typical air space factor. That has been what myself and others often came up with over the years.

Your method of calculating an estimate was interesting read. Only four logs different from what I came up with. Also, what I’ve generally seen as the case over the past 20 years or so :cool:
 
In my experience, ten 16' logs averaging a foot in diameter will turn into a stacked cord more or less. No tape measure required, but I do need to take my mitts off.

Or - if you have a tree service friend - ONE 16' log ~3' in diameter will do it too.
one 16 ft log, Let's say... 12 inches at the big end... about 10 inches in the middle??
8.73 cubic feet per log (my program, sez so) times 10... 87.3 cubic feet. Close.. Throw in one slightly larger log, and you got it.

Close enough.
 
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