How Much Coal or Firewood Do I Need? Estimating by Square Metre

There is no single correct answer to “how many tonnes of coal does a 100 m² house need?” — and anyone who gives you one number is guessing. Two houses of the same size can burn twice as much fuel as one another depending on insulation and habits. Instead of a fixed figure, this article explains which variables matter and by how much, and how to arrive at a sensible range.

The Six Variables That Set Your Needs

1. Heated Floor Area

What matters is not the total size of the house but the area you actually heat. If you heat only the living room and one bedroom of a 120 m² home, calculate on about 70 m². In stove-heated homes this gap can be large.

2. Insulation

This is the second and most decisive factor. Between an insulated flat with double glazing and good seals and an uninsulated house with single glazing and draughty doors, consumption easily differs by 40-50%. In an uninsulated house, even the most expensive fuel will not fully close that gap.

3. Ceiling Height

Heating is really a question of cubic metres, not square metres. A flat with a standard 2.60 m ceiling and an old village house with 3.20 m ceilings differ significantly in volume at the same floor area. If your ceilings are high, take your estimate from the upper end of the range.

4. Heating System: Stove or Central Heating?

A stove heats one point and the warmth fades room by room, leaving closed rooms cold. A central heating boiler warms the whole house evenly — comfort is higher, and so is total consumption. Automatic systems such as pellet stoves modulate to demand and can use less fuel per unit of heat delivered.

5. The Fuel's Calorific Value

If you heat with high-calorie imported coal, your tonnage will be noticeably lower than with low-calorie domestic lignite. So the answer to “how many tonnes?” changes with the product. Compare on total seasonal cost, not on tonnage.

6. Region and Climate

This is the point that matters most for our customers around Ödemiş. Most of the calculation tables you find online are built for Central and Eastern Anatolian conditions. In Ödemiş and the inland Aegean the heating season is shorter and winter averages are milder. High-altitude settlements such as Bozdağ are the exception: there the season is longer and consumption higher. Apply a table written for Ankara or Erzurum directly to Ödemiş and you will substantially over-order.

Rough Ranges (Aegean / Ödemiş Conditions)

The figures below are rough estimates, not exact numbers. They assume a home with moderate insulation, standard ceiling height and regular heating through the whole season. Your own house may fall below or above these ranges.

Stove-heated, roughly 80-100 m²: around 1-1.5 tonnes of high-calorie imported coal per season; around 2-3 tonnes of domestic lignite; or roughly 4-6 steres of dry hardwood.

Stove-heated, roughly 120-150 m²: around 1.5-2.5 tonnes of imported coal; around 3-4.5 tonnes of domestic lignite; or roughly 6-9 steres of firewood.

Detached house with a central heating boiler (150 m² and above): because you heat the whole house, needs rise markedly; around 3-5 tonnes of imported coal is a realistic starting band. Boiler efficiency and the state of the installation shift this considerably.

For uninsulated buildings: take the top of each range and add a margin. Insulation work pays for itself in fuel savings within a few seasons.

Use Our Calculator

For an estimate specific to your home, try our heating calculator. Enter your floor area, insulation level and heating system and it will return a range. That result is also an estimate; the exact amount depends on how you use the system.

Buying Strategy: All at Once or in Two Parts?

Once you have an estimate you have two options. Buying the whole season at once is usually better on unit cost and keeps you clear of the November rush — but it needs dry storage with enough space.

If storage is tight, split the season: take about two thirds in September and October and top up in January. That solves the storage problem and removes any risk of running out mid-season.

If you are unsure about your estimate, send us your floor area, insulation level and heating system on WhatsApp and we will give you a realistic range based on what comparable homes in the area actually use. Products and starting prices are in the current list below this article.