In a German owners association (WEG) anything beyond upkeep of common property needs a resolution (§ 20 (1) WEG). Five measures can be demanded as of right, provided they are appropriate and neither fundamentally alter the complex nor unfairly disadvantage an owner: accessibility, EV charging, burglary protection, fibre, plug-in solar. The community decides how; whoever demands one normally pays (§ 21 (1) WEG).
That became possible with the WEG reform (WEMoG, in force since 1 December 2020). This guide explains what structural alterations are, which privileged measures you can demand, where the limits lie and who ultimately pays, with the relevant provisions from § 20 and § 21 WEG.
What are structural alterations?
Under § 20 (1) WEG, structural alterations are all measures that go beyond the proper upkeep of the common property. While upkeep preserves or restores the existing condition (maintenance and repair), a structural alteration creates something new or changes the substance and appearance of the property.
Typical examples are installing a charging station in the underground car park, adding a ramp or a lift, replacing the flat’s entrance door with a burglar-resistant one, laying fibre into the flat, or fitting a balcony solar device. The decisive question is always whether the measure affects the common property. Pure changes within the individual unit that do not touch the common property are not structural alterations within the meaning of § 20 WEG.
The principle: nothing without a resolution
Under § 20 (1) WEG, structural alterations can be resolved or permitted to an owner by resolution. This is the central fork in the road: there are two routes.
- The community resolves a measure for everyone (for example a lift for the whole building).
- An individual owner is permitted to carry out a measure at their own expense (for example their personal charging point).
In both cases a resolution of the owners meeting is required. Building on one’s own initiative without a resolution is not allowed and may give rise to an obligation to remove the works and restore the original condition. Since the WEMoG a simple majority resolution suffices for permission; the consent of all affected owners, as required in the past, is no longer necessary.
The privileged measures: what you have a claim to
The real progress lies in § 20 (2) WEG. Under it, every owner may demand reasonable structural alterations that serve certain privileged purposes. Here there is a genuine claim as to the whether: the community cannot simply refuse a reasonable measure. The community must, however, resolve on the execution within the scope of proper administration, so it continues to steer the how.
| No. | Privileged measure (§ 20 (2) WEG) | Example |
|---|---|---|
| 1 | Use by people with disabilities (accessibility) | Ramp, lift, wider doors, handrails |
| 2 | Charging of electrically powered vehicles | Wallbox at the parking space, supply line in the car park |
| 3 | Burglary protection | Burglar-resistant flat or building door, locking system |
| 4 | Connection to a very high capacity telecommunications network | Fibre into the flat (FTTH) |
| 5 | Electricity generation by plug-in solar devices | Balcony solar device on balcony or facade |
Note: Number 5 (plug-in solar devices) was added after the first version of the law and is now expressly part of the catalogue in § 20 (2) WEG. The focus of most WEG debates, however, remains the charging point, accessibility and fibre.
Accessibility
Measures that serve use by people with disabilities have long been the classic claim. They include ramps, a retrofitted lift, wider doors or handrails in the stairwell. The claim is not limited to the affected owner; it also applies where a member of the household depends on the measure.
Charging point and charging of electrically powered vehicles
Charging electric vehicles is in practice the most common privileged measure. Anyone who owns a parking space as part of their unit or holds an exclusive right of use can demand the installation of a charging device. The community may regulate the how, for example a uniform load management, the routing of the supply line, or a common operator. How several charge points share one service connection, and what applies to a balcony power plant, is covered in the guide to wallbox, load management and PV in a condominium.
Burglary protection
This covers burglar-resistant flat and building entrance doors, additional locking technology, or secure lighting in the entrance area. Here too the individual owner can demand permission.
Fibre
Connection to a very high capacity telecommunications network essentially means laying fibre into the flat. Given the broadband roll-out, this is one of the most practically relevant claims for the value and lettability of a flat.
The limits: fundamental redesign and unfair disadvantage
The claim is not without limits. Under § 20 (4) WEG, structural alterations may not be resolved or permitted if they
- fundamentally redesign the property, or
- unfairly disadvantage an owner relative to others without that owner’s consent.
These two limits also apply to the privileged measures. A charging point, for instance, may not be carried out in a way that fundamentally changes the character of the property or unreasonably impairs another owner’s parking space. Outside the privileged catalogue, an owner may demand a measure under § 20 (3) WEG if everyone whose rights are impaired beyond the level unavoidable in orderly communal living consents.
Costs and benefits: whoever pays may use
Who bears the costs is governed by § 21 WEG. The principle is in paragraph 1: the costs of a structural alteration that was permitted to an owner or that was carried out on that owner’s demand under § 20 (2) are borne by that owner. That owner alone is then entitled to the benefits. So anyone who demands their own charging point pays for it themselves and uses it alone.
There are two important exceptions in which all owners share costs and benefits (§ 21 (2) WEG):
- The measure was resolved with more than two thirds of the votes cast and half of all co-ownership shares, unless it involves disproportionate cost.
- The costs of the measure amortise within a reasonable period (for example because the measure permanently saves energy or effort).
In all other cases, under § 21 (3) WEG the owners who resolved the measure bear the costs in proportion to their shares; only they are entitled to the benefits. An owner who was not initially involved may later demand participation against reasonable compensation (§ 21 (4) WEG). Finally, under § 21 (5) WEG the community may resolve a deviating allocation of costs and benefits. How these subsections play out for a measure covering the whole building is worked through for a heating replacement in the guide to the energy retrofit of a condominium.
Charging point example: Owner A demands a charging station for her parking space in the underground car park. The meeting permits the measure and stipulates that a common load management is used (the how). A bears the costs of her charging point including the supply line alone and uses it alone (§ 21 (1) WEG). If the community later resolves a charging base infrastructure for all parking spaces with more than two thirds of the votes and half of the co-ownership shares, all owners bear that base infrastructure together (§ 21 (2) WEG).
The practical process: from request to execution
In practice a structural alteration proceeds in orderly steps:
- Submit a request. The owner who wants to build approaches the manager in good time and describes the measure as concretely as possible (type, location, scope, cost, contractor).
- Add an agenda item. The manager puts a clear, decidable item on the agenda of the next owners meeting. A precise draft resolution that separates the whether from the how is essential.
- Pass the resolution. The meeting resolves the permission or the measure itself. For privileged measures there is a claim as to the whether; disputes usually concern only the how.
- Clarify costs and benefits. The resolution should clearly state who bears the costs and who is entitled to the use (§ 21 WEG), to avoid later disputes.
- Carry out and document. Building only starts after the resolution. The manager and the owner should document execution and acceptance, especially for interventions in the common property.
A clean draft resolution decides almost everything here: it must separate the whether from the how, name the cost allocation, and describe the execution concretely enough for the resolution to become final. That is precisely the task of professional condominium management in Frankfurt, which checks requests, drafts resolutions and accompanies the measures. For let units, individual unit management additionally coordinates the interface between owner, tenant and community. Anyone re-organising their administration should look for certified property management with proven expertise.
Since the WEMoG, structural alterations are no longer taboo but a right that can be shaped. Anyone who knows the claim under § 20 (2) WEG, separates the whether from the how, and settles the cost question of § 21 WEG cleanly in the resolution brings a charging point, accessibility or fibre into the building without needless conflict.
Sources
Editorial responsibility: digo.immo Verwaltung & Invest - certified residential property manager under § 26a WEG (IHK Frankfurt), licence under § 34c GewO. About the certification
This article provides general information only and does not replace individual legal advice. It was created with AI assistance; the legal statements have been checked against the official texts of the law. Legal status: 28/08/2026; laws and case law may change. No warranty is given as to completeness, accuracy or timeliness. When in doubt, please seek qualified advice.