Renovating an owned flat in Berlin: what you can do independently and what the WEG decides

When renovating an owner-occupied flat in Berlin, one question determines almost everything: are you affecting individually owned property or common property? You can generally replace floor coverings, internal walls, bathroom surfaces and sanitary fittings yourself. Windows, the flat's entrance door, load-bearing walls, screed and service pipes, however, belong to the homeowners' association — these require a WEG resolution. Berlin also has neighbourhood protection rules, which affect owner-occupiers too. This guide shows what you can do independently, what the WEG decides and what costs to expect.

Key points at a glance

• Individually owned property (can be renovated independently): floor coverings, non-load-bearing internal walls, internal doors, surfaces, sanitary fittings
• Common property (WEG resolution required): windows, flat entrance door, load-bearing walls, screed, façade, risers and heating pipes¹
• According to the BGH, windows (including frames) and the flat entrance door are necessarily common property — even if the declaration of division says otherwise⁴
• Since the 2020 WEG reform, structural alterations to common property are approved by a simple majority (§ 20 WEG); the person requesting them usually bears the costs (§ 21 WEG)
• In Berlin's neighbourhood protection areas, modernisation requires approval — whether you let the property or live in it yourself⁵

Individually owned or common property — what can I do independently?

Individually owned property comprises the rooms in your flat and components you can alter without unreasonably affecting the common property or other owners (§ 5 Abs. 1 WEG). By contrast, any parts necessary for the building's continued existence and safety, or serving communal use, cannot be individually owned — they are necessarily common property, even when located inside your flat (§ 5 Abs. 2 WEG).¹

The declaration of division is always the first reference point. However, it cannot override the statutory boundary under § 5 Abs. 2 WEG — which is why conflicting window or door clauses regularly fail in court. The Federal Court of Justice expressly classified windows including frames (judgment V ZR 174/11) and the flat entrance door (V ZR 212/12) as common property.⁴

Which measures require a WEG resolution?

As soon as a measure goes beyond simple maintenance and changes common property, it constitutes a structural alteration under § 20 WEG and must be approved by the owners' meeting or authorised for you by resolution.² Since the WEG reform (in force since 1 December 2020), a simple majority of votes cast has been sufficient — previously, all affected owners had to agree. In principle, the person requesting the measure bears the costs and is also entitled to its benefits (§ 21 Abs. 1 WEG). Costs are shared by all owners only if more than two thirds of the votes and half of all co-ownership shares approve, or if the measure pays for itself within a reasonable period (§ 21 Abs. 2 WEG).³ You even have a right to certain privileged measures — accessibility, electric vehicle charging, burglary protection and fibre-optic connections.

In practice, this means a new bathroom in the same position is usually possible independently — but as soon as you affect the screed, move risers or open up a load-bearing wall, you need a resolution. For work on the entire building (façade, roof, WEG heating system), see the guide to WEG renovation.

What does renovating an owned flat in Berlin cost?

Costs depend mainly on the scope: cosmetic refurbishment in Berlin costs 300 to 600 euros per square metre, standard renovation including the bathroom, electrics and floors costs 800 to 1.400 euros, and complete renovation costs 1.400 to 2.500 euros per square metre. Berlin is 10 to 25 per cent above the national average. You will find a breakdown by trade in the 2026 cost overview, and you can use the renovation cost calculator for a quick assessment of your project. Please note: if your flat is in an older building, allow for risks relating to hazardous materials and the building's condition — details in our guide to renovating older buildings in Berlin.

Neighbourhood protection also applies to owner-occupiers

In Berlin's 82 social conservation areas, all modernisation measures require approval — regardless of whether you let the flat or live in it yourself. Approval is required because of the building work, not the letting status; district offices provide a dedicated application form.⁵ Upgrades such as a second bathroom or opening up the layout may also be prohibited for owner-occupiers. Clarify your address's protection status with the district office before planning.

Frequently asked questions

What can I renovate independently in my owned flat in Berlin?

Anything that is exclusively individually owned property: floor coverings, non-load-bearing internal walls, internal doors, wall and ceiling surfaces, and sanitary fittings. As soon as you affect load-bearing walls, windows, the flat entrance door, screed or communal pipes, you are dealing with common property (§ 5 Abs. 2 WEG) — and need a resolution under § 20 WEG.

Do windows and the flat entrance door belong to my flat or to the WEG?

Both are necessarily common property, even if the declaration of division says otherwise. The BGH ruled this for windows including frames (V ZR 174/11) and the flat entrance door (V ZR 212/12). An individual owner therefore cannot arrange replacement unilaterally — it is a matter for the association.

Do I need a WEG resolution to renovate the bathroom in my owned flat?

Generally not for simply replacing tiles, taps and sanitary fittings in the same positions — these are individually owned property. A resolution under § 20 WEG becomes necessary as soon as you affect the screed, move risers or drainage pipes, or open up a load-bearing wall. If in doubt, check with the property manager beforehand and consult the declaration of division.

Who pays for a structural alteration I request for my flat?

You do. Under § 21 Abs. 1 WEG, the owner requesting an authorised structural alteration bears its costs alone — and is also entitled to its benefits. Costs are shared by all owners only if the measure is approved by more than two thirds of the votes and half of all co-ownership shares, or if it pays for itself within a reasonable period.

Does Berlin's neighbourhood protection also apply to owner-occupiers?

Yes. Modernisation measures in social conservation areas require approval — whether you let the property or live in it yourself. The requirement is linked to the building work; district offices provide a dedicated application form. Upgrades such as a second bathroom may also be prohibited for owner-occupiers.

For an initial estimate of your flat renovation costs, use the renovation cost calculator. Our guide shows how to find the right company: Finding & comparing renovation companies.

Sources

1. § 5 WEG, subject matter and scope of individual ownership (Abs. 2: mandatory common property)
2. § 20 WEG, structural alterations (resolution of the owners' meeting)
3. § 21 WEG, benefits and costs of structural alterations
4. BGH, judgment of 02.03.2012, V ZR 174/11: windows including frames are necessarily common property (and V ZR 212/12 on flat entrance doors)
5. Berlin Reinickendorf District Office, social conservation regulations (neighbourhood protection): approval requirement for modernisation, including for owner-occupiers