Pellet stove size by square footage: a complete guide to choosing the ideal heating capacity

Are you thinking about installing a pellet stove but unsure what heating capacity you need? Choosing the right size is key to enjoying optimal comfort, efficient consumption and genuine savings on your heating bill. An oversized stove wastes energy and money; an undersized one will leave you cold.

In this guide, we explain how to calculate exactly how many square metres a pellet stove can heat, which factors affect the heating capacity you need and which Ecoforest models are best suited to each type of home.

How many square metres can a pellet stove heat?

The answer depends on three main factors:

1. Stove output (kW): the higher the output, the greater the heating capacity.
2. Home insulation: thick walls, double-glazed windows and good draught-proofing reduce heat loss.
3. Climate zone: heating a home in Galicia is not the same as heating one in Andalusia.

As a general rule of thumb:

• 1 kW heats between 8 and 10 m² in mild climates and well-insulated homes.
• 1 kW heats between 6 and 8 m² in cold climates or poorly insulated homes.

But this is only an estimate. To make the right choice, you need a more precise calculation.

How to calculate the pellet stove output you need: a step-by-step method

Step 1: Calculate the volume (m³) of your home

Knowing the floor area is not enough; ceiling height also matters.

Formula:

Volume (m³) = Floor area (m²) × Height (m)  

Example:

• An 80 m² home with 2,5 m ceilings:
  80 m² × 2,5 m = 200 m³

Step 2: Determine the kW/m³ coefficient based on insulation and climate

This coefficient varies according to two key factors:

Table: kW/m³ coefficient by insulation and climate

Example:

• A 200 m³ home in Madrid (moderate climate) with average insulation:
  Coefficient = 0,040 kW/m³

Step 3: Calculate the required output

Formula:

Required output (kW) = Volume (m³) × Coefficient (kW/m³)  

Example:

• 200 m³ × 0,040 kW/m³ = 8 kW

In this case, you would need a pellet stove rated at between 7,5 and 9,5 kW to heat your home comfortably.

💡 Expert tip: If your home has several floors or rooms far apart, consider a ducted stove that distributes warm air through ducts. If it is an open-plan space or has just a few adjoining rooms, an air stove will be sufficient.

Summary table: Stove output by floor area and climate

To make your choice easier, here is a guide to recommended outputs by floor area and conditions:

Ecoforest pellet stoves: which is ideal for your home?

Ecoforest offers a wide range of pellet stoves with different outputs, designs and features. Here, we help you choose based on your floor area:

For homes of 50–60 m² (mild climate or good insulation)

Miami – 5,5 kW

• Ideal for small apartments, studio flats or holiday homes.
• Compact, modern design.
• Perfect for spaces of up to 55 m² with good insulation.

Recommended for: city flats, beach apartments, small country houses.

For homes of 60–75 m²

Creta – 6 kW

• Air stove with an elegant design.
• Efficient heating for spaces of up to 60 m².

Lyon – 7,5 kW

• Versatile output for homes of up to 75 m².
• Excellent value for money.

Monaco – 7,5 kW

• Slim design, ideal for hallways and small spaces.
• Perfect for long, narrow layouts.

Moon II – 7,5 kW

• Modern, minimalist look.
• Excellent flame visibility.

Nature – 7,5 kW

• Rustic, fireplace-style design.
• Perfect for vintage interiors or country houses.

Recommended for: 2–3-bedroom flats, small terraced houses, areas with a mild climate.

For homes of 80–100 m²

Eco Mini Insert – 8 kW

• Insert stove, ideal for fitting into existing fireplaces.
• Combines existing structures with modern technology.

Vigo III – 9,5 kW

• Contemporary design with high performance.
• Heats up to 95 m² under average conditions.

Keops – 9,5 kW

• Elegant lines and advanced functionality.
• Perfect for spacious living rooms.

Marsella – 9,9 kW

• Output suited to medium-sized homes.
• Excellent energy efficiency.

Recommended for: three-bedroom detached houses, spacious flats, areas with a moderate climate.

For homes of 100–130 m² or cold climates

Lisboa – 11,9 kW

• High output for large or poorly insulated spaces.
• Heats up to 120 m² under normal conditions.

Cordoba – 12 kW

• Built-in air stove.
• Wall-integrated design, perfect for renovations.

Cordoba Glass – 12 kW

• Version with panoramic glass.
• Maximum flame visibility and premium design.

Praga – 12 kW

• High-capacity air stove.
• Ideal for two-storey homes or open-plan spaces.

Tokio – 12 kW

• Modern, functional design.
• Perfect for spacious living rooms and seating areas.

Recommended for: detached houses, two-storey homes, homes in cold areas, spaces with average insulation.

For homes larger than 130 m² or small buildings

Eco I – 13,5 kW

• High output for large floor areas.
• Heats up to 135 m² under average conditions.

Eco I Insert – 13,5 kW

• Insert version of the Eco I model.
• Fits seamlessly into existing fireplaces or openings.

Atenas – 14 kW

• The highest-output stove in the Ecoforest range.
• Ideal for homes larger than 140 m², small buildings or very cold areas.

Recommended for: large detached houses, country houses, buildings with two full floors, mountain areas.

At a glance: Air stove or ducted stove?

Air stove

• Fans release heat from the front of the stove.
• Ideal for open-plan spaces, spacious living rooms or single-storey homes.
• More affordable and easier to install.

Ducted stove

• Distributes warm air through ducts to several rooms.
• Perfect for multi-storey homes, long hallways or rooms far apart.
• Requires a more complex installation but provides comfort throughout the home.

Ecoforest advice: If your home is larger than 100 m² and has several rooms or floors, a ducted stove will provide much more even heating.

How much does a pellet stove consume?

Pellets are one of the most efficient and sustainable fuels:

• Efficiency above 90% (compared with 70% for firewood).
• Lower smoke and odour emissions.
• Eco-friendly, renewable fuel, with ENplus A1 certification.

Consumption depends on:

• Stove output.
• Hours of daily use.
• Outdoor temperature and insulation.

Estimated consumption:

• 7,5 kW stove under moderate use: 1,5–2 kg/hour → 12–16 kg/day.
• 12 kW stove under intensive use: 2,5–3,5 kg/hour → 20–28 kg/day.

With pellets priced at 0,30–0,40 €/kg, the daily cost ranges from 4 to 11 €, much less than heating oil or electricity.

Frequently asked questions (FAQ)

How many kW do I need to heat 100 m²?

It depends on insulation and climate:

• Good insulation + mild climate: 8–10 kW.
• Average insulation + moderate climate: 10–12 kW.
• Poor insulation + cold climate: 12–14 kW.

Can I heat my entire home with a single pellet stove?

Yes, if you choose a ducted stove with the right output and a well-designed duct layout. For homes larger than 100 m² or with several floors, it is the best option.

What happens if I buy a stove with more output than I need?

• You will use more pellets than necessary.
• The stove will run in short cycles (switching on and off), which reduces its lifespan.
• You will lose efficiency and comfort.

What if I buy a stove with too little output?

• You will not reach your desired temperature.
• The stove will always run at maximum output, causing more wear.
• You will use more pellets trying to compensate for the lack of output.

Conclusion: choose wisely and enjoy a comfortable winter

Calculating the correct output for your pellet stove is essential to:

• Save on pellet and electricity consumption.
• Enjoy genuine comfort in every room.
• Extend the lifespan of your equipment.

Ecoforest pellet stoves offer:

• A wide range of outputs (from 5,5 to 14 kW).
• Designs for every taste and space.
• Advanced technology, efficiency and sustainability.
• Technical support and a network of professional installers.

Not sure which model to choose? Contact an Ecoforest installer or the brand’s technical team. They will help you choose the right stove size for your home, climate and needs.