Tax bonus under § 35c EStG: requirements and relation to the BEG
Tax bonus under § 35c EStG for owner-occupied homes: requirements, maximum amounts, specialist contractors, certificate and relation to the BEG.
Read articleTopic archive
Category: Cost-effectiveness
Articles on building physics, application and cost-effectiveness.
BEG grant for the building envelope: application route since July 2026
BEG funding for the building envelope: who may apply, what counts as project start, and which evidence and deadlines BAFA has required since July…
Read article
Calculating payback properly: savings, price, interest, funding
A payback model covering savings, energy price, interest and funding, a neutral worked example and the limits of the simple calculation.
Read article
GEG Is Now GModG: What Applies to the Facade from 29 July 2026
Since 29 July 2026, Germany's Buildings Energy Act (GEG) is called the Buildings Renovation Act (GModG). Which sections were renumbered, what stays the same…
Read article
The Degree-Day Method: What the Calculation Can Do, and Where It Stops
Q = U · A · Gt · 24 / 1000 — the method behind every rough savings estimate, its five blind spots, and…
Read article