Germany's Building Modernization Act (GModG) Enters Force

The Building Modernization Act (Gebäudemodernisierungsgesetz, GModG) was published in the Federal Law Gazette on 28 July 2026 and began to apply on 29 July 2026. Immediate changes include the removal of the previous 65 % renewable‑energy requirement for new heating systems, the lifting of bans on oil and gas boilers, new rules for the exchange and installation of heating equipment, and a revised allocation of CO₂ costs between landlords and tenants.

Further provisions are phased in: on 1 January 2027 the law adopts EU building‑directive standards, sets minimum energy standards for certain non‑residential buildings, introduces solar obligations, updates energy‑certificate requirements and mandates lifecycle‑based eco‑balancing for new constructions. On 1 January 2028, zero‑emission building rules apply to new public‑sector non‑residential buildings, and by 1 January 2030 a zero‑emission target is established for all new non‑residential buildings.

Federal President Frank‑Walter Steinmeier signed the act on 23 July 2026. While the Verband Deutscher Kälte‑Klima‑Fachbetriebe (VDKF) welcomed the legislation for the planning certainty it provides, the environmental group Deutsche Umwelthilfe (DUH) argues that the law may conflict with Germany’s climate protection goals and plans to seek a constitutional review.