Fire Wood - the Cord
The chord is the most commonly used measurement unit for purchasing fuel wood.
A cord is a stacked unit volume of wood where
1 cord = (4 ft) (4 ft) (8 ft)
= 128 cubic feet
or in metric units
1 cord = (1.22 m) (1.22 m) (2.44 m)
= 3.62 m3
This volume includes bark and air space. Due to the irregular shape of wood the air space in the cord can be as high as 40 percent. The net cord volume can therefore be as low as 75 cubic feet. In general net cord volume ranges 80 - 100 cubic feet.
- 1 ft (foot) = 0.3048 m
- water content in wood
How to Calculate the Cords
To calculate the number of cords in a pile of fire wood - measure the length (l), the width (w) and the height (h) of the pile. Calculate the volume of the pile and divide the volume with 128 if your unit is feet - or with 3.62 if your unit is m.
Example - Calculate the number of Cords
A pile with fire wood is 12 ft long, 2.5 ft wide and 6 ft high. The number of cords in the pile can be calculated as
(12 ft) (2.5 ft) (6 ft) / 128
= 1.4 cord
A pile with fire wood is 6 m long, 1.2 m wide and 1.5 m high. The number of cords in the pile can be calculated as
(6 m) (1.2 m) (1.5 m) / 3.62
= 3 cord
Typical Firewood
- Ash, white - Hardwood - Good firewood
- Beech - Hardwood - Good firewood
- Birch, yellow - Hardwood - Good firewood
- Chestnut - Hardwood - Excessive sparking, can be dangerous
- Cottonwood - Hardwood - Good firewood
- Elm, white - Hardwood - Difficult to split, burns well
- Hickory - Hardwood - Slow steady fire, best firewood
- Maple, sugar - Hardwood - Good firewood
- Oak, red - Hardwood - Slow steady fire
- Oak, white - Hardwood - Slow steady fire
- Pine, yellow - Softwood - Quick hot fire, smokier than hardwood
- Pine, white - Softwood - Quick hot fire, smokier than hardwood
- Walnut, black - Hardwood - Good firewood
Related Topics
• Combustion
Boiler house topics, fuels like oil, gas, coal, wood - chimneys, safety valves, tanks - combustion efficiency.
Related Documents
Biomasses - Energy Content when Used as Fuel
Biomass fuels and their energy content.
Hardwood and Softwood Species
Species of hardwood vs. softwood.
Lumber - Weights
Weights of green, kiln dried and pressure treated lumber boards.
Softwood Lumber - Standard Sizes
Nominal and minimum-dressed lumber sizes.
Tree Species - Water Demand
Trees species and relative water demand.
Urban Tree Heights
Height of trees commonly used in towns and urban areas.
Wood - Combustion Heat Values
Combustion of wood and firewood heat values for species like Pine, Elm, Hickory and more.
Wood - Compressive Strength vs. Moisture Content
Red Spruce, Longleaf Pine and Douglas Fir - moisture content and their compressive strength.
Wood - Density vs. Moisture Content
The density of wood versus moisture content.
Wood and Bio Mass - Combustion Heat
Combustion heat values for wet and dry wood - Btu/pounds, kJ/kg and kcal/kg.
Wood Species - Densities
Densities of various wood species - apple, ash, cedar, elm and more.
Wood Species - Moisture Content and Weight
Weight of green and air-dried fire wood.