How Many Sacks and Steres in 1 Tonne of Firewood? How Many Tonnes Is 4 Steres?

Short answer: with 25 kg sacks, 1 tonne of firewood is 40 sacks; with 20 kg sacks, 50. Türkiye's General Directorate of Forestry (OGM) takes an average stere as 500 kg, so 1 tonne is about 2 steres, 4 steres about 2 tonnes and 6 steres about 3 tonnes. Real weight varies with species, piece thickness and moisture.

Current prices and types: Firewood prices →

What is a stere?

A stere is the amount of wood stacked in a 1 m³ space; the gaps between pieces count towards that volume, so the solid wood in a stere is less than 1 m³. According to an OGM research bulletin, OGM assumes a stere holds on average 0.7 m³ of solid wood and weighs 500 kg; the same bulletin stresses that in reality the volume and weight of each stere vary a lot with species, piece size, whether the wood is green or dry, and how carefully it is stacked. FAO's conversion table likewise gives 0.65 m³ of solid volume per stere of fuelwood.

How many tonnes is a stere of firewood?

With the OGM average, multiply the number of steres by 500 kg. The second column shows how a light species deviates: in OGM's Eastern Anatolia study, an air-dry stere of Scots pine weighed about 266 kg.

By the same arithmetic, 15 steres is about 7.5 tonnes and 20 steres about 10 tonnes. A stere of a dense hardwood such as oak can weigh more than average, but we found no measured Turkish stere weight for oak. A rough check: FAO gives fuelwood densities of 750 kg/m³ for non-coniferous and 625 kg/m³ for coniferous wood; 0.65 m³ × 750 ≈ 490 kg and 0.65 × 625 ≈ 405 kg per stere.

How many steres and cubic metres is 1 tonne of firewood?

With the OGM average, 1 tonne is about 2 steres. Since a stere is a stacked volume, that is about 2 m³ of stack; the solid wood inside is 2 × 0.7 = 1.4 m³ by OGM's figure or 2 × 0.65 = 1.3 m³ by FAO's. Part of the weight of green wood is water, so a tonne of green wood means less wood and less heat; for heat per tonne see our guide How many calories in firewood?.

How much space does 1 tonne of firewood take?

About 2 m³ when neatly stacked: for example 2 m long, 1 m high and 1 m deep. 2 tonnes by the same arithmetic need about 4 steres, i.e. 4 m³ of stack. A loose pile takes more: according to Forest Research's technical supplement, 1 m³ of loose wood is about 0.66 m³ stacked, so 1 tonne (2 m³ stacked) piled loosely takes roughly 2 ÷ 0.66 ≈ 3 m³. Light species and large, crooked pieces need more.

In storage, raise the wood off the ground and cover only the top, leaving the sides open; details in how to dry firewood.

How many sacks are in 1 tonne of firewood?

Divide 1,000 kg by the sack weight. Sack weights are on the product pages: dry oak firewood comes in 20-25 kg sacks, red oak in 28 kg and yellow oak in 30 kg sacks.

How many bags are in 1 tonne of coal?

The arithmetic is the same: with 25 kg bags, 1 tonne of coal is 40 bags. For bag weights and other coal-bag questions, see how heavy is a bag of coal.

How many tonnes or steres should I buy?

That depends on the size of the home, its insulation and your stove. For ranges see how much coal or firewood do I need, and for an estimate for your own home use our fuel calculator.

What does it depend on?

• Species: a stere of a dense species weighs more; 1 tonne of oak is fewer steres than 1 tonne of pine.
• Moisture: part of green wood's weight is water; OGM measured stere weights falling over time after felling.
• Piece thickness: according to OGM, as the diameter of the pieces decreases, the stere conversion factor and stere weight fall.
• Stacking: a neat stack takes less space than a loose pile.

Safety

Burning wood also produces carbon monoxide. The CDC describes it as an odourless, colourless gas; with headache, dizziness or weakness, ventilate, leave the room and call 112, the emergency number in Türkiye. See stove gas symptoms and carbon monoxide detectors.

Frequently asked questions

How many tonnes is 4 steres of firewood?

About 2 tonnes with OGM's 500 kg/stere. Light species can weigh less: Eastern Anatolian Scots pine gives 4 × 266 = 1,064 kg.

How many tonnes is 6 steres of firewood?

About 3 tonnes with the average (6 × 500 kg).

How many steres is 1 tonne of firewood?

About 2 steres; it varies with species and moisture.

How much space do 2 tonnes of firewood take?

About 4 m³ (4 steres) neatly stacked; more as a loose pile.

How many cubic metres is 1 tonne of firewood?

About 2 m³ of stack; the solid wood inside is 1.3–1.4 m³ (FAO and OGM factors).

Sources: General Directorate of Forestry (OGM), Eastern Anatolia Forestry Research Institute, “Stere conversion factors of Scots pine fuelwood in Eastern Anatolia” (stere definition, 0.7 m³ and 500 kg, Scots pine 266 kg/stere, diameter effect); FAO, “Conversion factors” (1 stere = 0.65 m³; fuelwood density); Forest Research, “Wood as Fuel – Technical Supplement” (1 m³ loose ≈ 0.66 m³ stacked); EPA Burn Wise (store with only the top covered); CDC, carbon monoxide.