Germany's Building Modernisation Act: What Renters and Expats Should Know

Introduction

Germany's newly passed Gebäudemodernisierungsgesetz (Building Modernisation Act) was designed to accelerate the energy-efficient renovation of the country's aging housing stock. But the law has run into a wall of criticism. During a Bundestag hearing, experts and industry associations voiced serious concerns — not just about the practical impact of the legislation, but about whether it is even constitutional. At least one association has announced it will pursue legal action to challenge the law. For expats living in Germany, particularly those renting apartments or planning long-term stays, this is a story worth following closely: renovation laws have a direct effect on rent levels, living conditions, and tenant rights.

What the Building Modernisation Act Proposes

The Gebäudemodernisierungsgesetz sets out requirements and incentives for modernising buildings to improve their energy efficiency. Germany has committed to ambitious climate targets, and the built environment — heating, insulation, and energy consumption in homes and offices — is a major part of that equation. The law aims to push property owners to upgrade older buildings with better insulation, modern heating systems, and other energy-saving measures.

In theory, more energy-efficient homes mean lower heating bills for residents. In practice, however, the path to get there is contentious. The costs of renovation work are substantial, and the question of who pays — and how much can be passed on to tenants — is at the heart of the controversy.

Why Critics and Associations Are Pushing Back

During parliamentary hearings, experts and industry groups raised two main lines of criticism.

First, there are constitutional concerns. Some legal experts argue that certain provisions of the law may exceed what the federal government is permitted to mandate, or that the financial obligations it creates for private property owners could be challenged as an disproportionate interference with property rights. One association has already announced plans to take the matter to court.

Second, critics point to the financial burden the law places on landlords and, by extension, tenants. German tenancy law allows landlords to pass on a portion of modernisation costs to tenants through rent increases. If large-scale renovations become mandatory, tenants in older buildings — a category that covers a huge share of Germany's rental housing — could see significant rent hikes. For expats already navigating a tight rental market in cities like Berlin, Munich, Frankfurt, or Hamburg, this is a very real concern.

What This Means for the Rental Market

Germany already has one of the most competitive rental markets in Europe, with demand far outstripping supply in major cities. Any law that increases costs for landlords without robust tenant protections risks accelerating rent increases or pushing landlords to sell rather than renovate.

At the same time, energy-efficient housing does offer genuine long-term benefits. Lower heating costs can offset higher base rents, particularly as gas and electricity prices remain elevated compared to pre-2022 levels. The key question is how the transition is managed and how tenant protections are structured within the law.

If the legal challenge proceeds and courts weigh in, implementation of parts of the law could be delayed or revised, introducing further uncertainty for both landlords and tenants.

Frequently Asked Questions

Can my landlord raise my rent because of renovation work under this law?

Under existing German tenancy law (§559 BGB), landlords can in certain circumstances pass on up to 8% of the renovation cost per year as a rent increase. The Gebäudemodernisierungsgesetz does not eliminate this mechanism. If your landlord plans renovation work, they are required to notify you in advance — typically at least three months before work begins. You should read any such notice carefully and, if needed, seek advice from a local tenants' association (Mieterverein).

Will this law make it harder to find an affordable apartment in Germany?

It is too early to say with certainty. If the legal challenges delay or water down the law, the immediate impact on the rental market may be limited. However, if widespread renovations are triggered, supply of affordable unrenovated flats could decrease and rents in renovated buildings could rise. Staying informed about how the law develops and monitoring rental listings in your city is the most practical step you can take right now.

What happens if the constitutional challenge succeeds?

If a court rules against the law or specific provisions within it, those parts would need to be revised by parliament or suspended pending a new legislative process. This could take months or years. In the meantime, the law as currently written remains in force unless a court orders a temporary injunction.

Conclusion and Next Steps

The Gebäudemodernisierungsgesetz is still in the early stages of being tested — both politically and legally. For expats living in rented accommodation in Germany, the most important thing right now is awareness. If you receive a renovation notice from your landlord, do not ignore it. Contact your local Mieterverein (tenants' association) for guidance. Keep an eye on how the legal challenge develops, as it could significantly change how and when the law is applied.

If you own property in Germany, speak with a legal or tax adviser about your obligations under the new legislation before making any investment decisions.

Source: tagesschau