I Burn About 3 ft3 Per Day

I burn about a cord in three weeks going full tilt 24/7 (Jan and Feb). There is about 85 cu.ft. in a stacked cord, so I guess I burn 4 cu.ft./day.

Which is strange because my stove is 2.5 cubic feet, but it seems like I fill it at least four times a day when the mercury plummets. Must be a lot more air space in there than I figured.

I thought a cord was 128 cu.ft. (4x4x8)?

spendaviscpa said:

I thought a cord was 128 cu.ft. (4x4x8)?

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me 2....thats what i get when i do the math....4 x 4 x 8 = 128 cu ft.

...but when you put wood in your stove there's air space.

FirewoodMan said:

...but when you put wood in your stove there's air space.

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Good Point!

BrotherBart said:

85 cubic feet after you take out the air space between the splits.

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where is that rule.....this is what i find:
The cord is a unit of measure of dry volume used in Canada and the United States to measure firewood and pulpwood. A cord is the amount of wood that, when "ranked and well stowed" (arranged so pieces are aligned, parallel, touching and compact), occupies a volume of 128 cubic feet (3.62 m3).[1] This corresponds to a well stacked woodpile 4 feet (122 cm) wide, 4 feet (122 cm) high, and 8 feet (244 cm) long; or any other arrangement of linear measurements that yields the same volume.

cass

Thought I was the only one who measured it that close... Last year when really cold I was running nearly 5 cu ft per 24 hour day, just shy of a month for a cord. (I figure a cord at 128 cu foot of space including the air between the pieces) However, it doesn't run that hard all that often. Right now, an armful each morning when we get into the thirties overnight is all it takes. Sometimes we've lit a small fire in the evenings too. Cold starts all the time are kindof a hassle but the two other choices are not desirable: 1) Natural gas furnace, or 2) open windows and keep coals in the stove all the time.

I don't know what is wrong with the rest of you but I don't have air space in my stacks they are perfect...... :lol:

BrotherBart said:

tcassavaugh said:

BrotherBart said:

85 cubic feet after you take out the air space between the splits.

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where is that rule.....this is what i find:
The cord is a unit of measure of dry volume used in Canada and the United States to measure firewood and pulpwood. A cord is the amount of wood that, when "ranked and well stowed" (arranged so pieces are aligned, parallel, touching and compact), occupies a volume of 128 cubic feet (3.62 m3).[1] This corresponds to a well stacked woodpile 4 feet (122 cm) wide, 4 feet (122 cm) high, and 8 feet (244 cm) long; or any other arrangement of linear measurements that yields the same volume.

cass

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All over the web. But here is one place. http://woodheat.org/cord-wood.html

But the OP didn't reference how much of a cord. He said cf of wood. No question about it. A stacked cord of wood takes up 128 cubic feet of space. But it ain't 128 cubic feet of wood.

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agreed, aint all wood. almost didn't recognize you with your new avitar

thats better.....now i recognize ya.

cass

Any aviator will tell you that one of the most useless things in the world is the airspace in your fuel tank...same with the airspace in my wood stacks. I burn as much wood as I need to burn to keep warm. On a cold day, that will likely mean burning hotter/longer, so more wood than on a milder day. Honestly, I've never paid any attention whatever to actually quantifying the fuel I burn. To make it meaningful, I'd think that, at a minimum, the species and weight should be specified. The volume doesn't really mean a heck of a lot by itself. Rick

128 down to 85 is a loss of 34%. I doubt my stacks have that much air, even if I let my wife do the stacking :snake:

fossil said:

Any aviator will tell you that one of the most useless things in the world is the airspace in your fuel tank...same with the airspace in my wood stacks. I burn as much wood as I need to burn to keep warm. On a cold day, that will likely mean burning hotter/longer, so more wood than on a milder day. Honestly, I've never paid any attention whatever to actually quantifying the fuel I burn. To make it meaningful, I'd think that, at a minimum, the species and weight should be specified. The volume doesn't really mean a heck of a lot by itself. Rick

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Probably something closer to weight and moisture content, if you want to get real technical. 50 lbs of 15% MC red oak is going to put out way more heat than 50 lbs 45% red oak...and 50 lbs of 15% MC osage orange is going to put out pretty close to equal heat as 50 lbs of 15% MC pine, but take up a whole lot less space in the process.

In case you are wondering, I have 0 empirical evidence to back up this claim....so take it for what it's worth.

Ouch, are you heating outside too? haha!

I burned about 3 cords total last year, started heating in Sept and shut it down in April.

Battenkiller said:

I burn about a cord in three weeks going full tilt 24/7 (Jan and Feb). There is about 85 cu.ft. in a stacked cord, so I guess I burn 4 cu.ft./day.

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lukem said:

fossil said:

Any aviator will tell you that one of the most useless things in the world is the airspace in your fuel tank...same with the airspace in my wood stacks. I burn as much wood as I need to burn to keep warm. On a cold day, that will likely mean burning hotter/longer, so more wood than on a milder day. Honestly, I've never paid any attention whatever to actually quantifying the fuel I burn. To make it meaningful, I'd think that, at a minimum, the species and weight should be specified. The volume doesn't really mean a heck of a lot by itself. Rick

Click to expand...

Probably something closer to weight and moisture content, if you want to get real technical. 50 lbs of 15% MC red oak is going to put out way more heat than 50 lbs 45% red oak...and 50 lbs of 15% MC osage orange is going to put out pretty close to equal heat as 50 lbs of 15% MC pine, but take up a whole lot less space in the process.

In case you are wondering, I have 0 empirical evidence to back up this claim....so take it for what it's worth.

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From what I understand you're right. No matter the wood pound for pound they hold about the same btu's...just that pine would take up a lot more room then say oak .

fossil said:

To make it meaningful, I'd think that, at a minimum, the species and weight should be specified. The volume doesn't really mean a heck of a lot by itself.

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Species does needs to be known, but the actual weight is not that important. You want to know the weight of the wood fiber in that volume. Oven-dry weights are available for numerous species on several engineering websites.

For example:

White oak has an oven-dry density of about 45 lbs/cu.ft. It's average shrinkage from green to oven-dry is about 8%, therefore a 128 cubic foot stack of green white oak has about .92 X 85 cu.ft. = 78 cu.ft. of dry wood fiber. The low heating value of a pound of wood fiber is about 7800 BTU. So... 78 X 45 = 3510 lbs. dry wood fiber X 7800 BTU/lb. = 27,400,000 BTU/cord. At 20% MCW, there is an additional 25% water in there. 3510 X .25 = 880 pounds water X 960 BTU/pound water evaporated = 842,400 BTU lost evaporating water inside the stove. 27,400,000 - 842,400 = 26.5 million BTU/cord of white oak at 20% MCW... just about what the published tables all say.

Everybody's correct. Species, moisture content and some measure of "how much" all need to be specified. Of course density information is available, and of course, a pound of Pine will take up more volume than a pound of Oak. But since measuring the actual volume of split firewood is problematic because it tends to not pack together tightly, weight would be a much more readily available parameter, as it's easy to determine. If you want to know the actual volume of wood you burned (sans the airspace) start with the weight and the density information and whatever else you know about correcting for moisture content and work backward from there. But if you want to have some idea of the energy you released from combustion of the wood (which is what's really important to us, I think), then knowing only the volume isn't going to really tell you squat. Rick