Attic Conversion: What Does It Cost?

Converting an attic costs an average of €20,000

The cost of converting an attic typically ranges between €10,000 and €30,000.

Many homeowners consider making use of their unused attic space. However, before starting any planning, you must clarify the legal requirements.

In most federal states, attic conversions require approval, especially when additional living space is created. Depending on the state, this might involve a building permit, an exemption procedure, or a notification process.

An attic conversion is a major renovation project involving multiple trades and factors, including:

• Roof stripping

• Insulation

• Flooring installation

• Number and type of windows

• Number and type of radiators

• Number and type of dormers

• Electrical installation

• Access – staircase

Depending on the roof’s condition and your preferences, the total cost usually ranges from €10,000 to €30,000.

Are There Any Grants Available?

There are various funding options, some of which can even be combined.

KfW Funding

Under programs for energy-efficient renovation and age-appropriate conversions, KfW provides funding that can also apply to attic conversions, such as for:

• Proper installation of energy-efficient roof windows

• Roof insulation

• Accessible bathroom installations

• Automated window systems

KfW programs you can use include:

• 151/152 – low-interest loans

• 430 – direct grants

For age-friendly renovations:

• 455 – subsidy program

BAFA Funding

If your attic renovation involves upgrading the heating system, you can also apply for funding from BAFA (Federal Office for Economic Affairs and Export Control) to support the modernization of heating systems and their components.

State and Local Programs

Many states and municipalities offer additional grants that can be combined with KfW programs.

Important: All applications for financial support must usually be submitted before the renovation work begins.

How Much Does a New Attic Staircase Cost?

The access to the attic is typically via a staircase, which can be installed indoors or outdoors.
Costs vary between €1,000 and €5,000, depending on material and design.

A simple pull-down attic ladder costs around €100 to €200.

What Do Electrical Installations Cost?

Electrical work should always be performed by a certified electrician, both for safety and insurance reasons.

Electricians often offer fixed-price packages. By comparing 2–3 local providers, you can usually get a fair price.

• Electrical installation: €500–700

• Light switches and outlets: €150–200 (flat rate)

How Much Do Roof Windows Cost?

Roof window prices depend on size, glass type, and functionality.
Including installation, expect €660–1,080 per window.

For roof exits or terraces:

• Pitched roof: Simple exit €3,000–5,000; roof terrace €15,000–20,000

• Flat roof: Roof terrace €4,000–5,000 (if structure allows)

A roof dormer (including installation) costs around €6,500 on average.

Tip: Dormers increase living space and light but require a building permit.

Heating the Attic

If your home has central heating, adding radiators costs around €120–1,500 each, depending on type and size.

Without central heating, electric or infrared heaters are an option—but expect higher running costs.

Partition Walls (Dry Construction)

For dividing rooms, drywall is the best choice.

• Drywall installation (including labor): €50–60/m²

• Wallpapering and painting: €10–20/m²

DIY work can reduce these costs significantly.

New Flooring

Installing flooring isn’t overly complex—DIY can save money.
Depending on material, expect €20–45/m², with parquet being especially popular for its warmth.

Roof Insulation

There are several insulation methods:

• Between-rafter insulation: €18–34/m² (affordable option)

• Above-rafter insulation: more expensive, requires complete roof replacement

Roof Clearance / Gutting the Attic

Gutting the attic costs around €20–30/m² if done by a contractor. You can reduce this cost by doing some work yourself.

This includes removing old fixtures, non-load-bearing walls, and systems like electrical, heating, or ventilation.
Also, any hazardous materials (e.g., asbestos) must be safely removed.

What Should You Consider?

Before starting, inspect the attic for structural issues—repair costs should be included in your budget.

Also, consider:

• The intended use of the attic

• Roof dormers cost more than skylights but add space

• The right balance between comfort, cost, and energy efficiency

Example Calculation: Attic Conversion

Scenario:
A single-family home’s attic (50 m²) will be converted.
The plan includes four roof windows, two radiators, and a flat-roof exit.
No additional walls are required.