Building Modernisation Act: What Owners Need to Know When Selling a House
More freedom in heating, new questions when selling
Since 29 July 2026, the Building Modernisation Act (GModG) has been in force, replacing the previous Building Energy Act. For owners planning a house sale or apartment sale, this changes the arguments in price negotiations. We explain what matters now.
The controversial 65 percent rule for new heating systems has been abolished. Owners may once again choose freely between heat pumps, district heating, hybrid systems, biomass and gas or oil heating. For sellers and buyers in Berlin-Pankow, Barnim and Oberhavel, the question is how the new legal situation affects property valuation and market value. Important to note: functioning existing heating systems may continue to operate.
The bio-fuel ladder: gas and oil will gradually become more expensive
Anyone installing a new gas or oil heating system must use a growing share of climate-friendly fuels: 10 percent from 2029, 15 percent from 2030, 30 percent from 2035 and 60 percent from 2040. From 2045, heating fuels are to be fully climate-neutral. Prospective buyers increasingly factor these future running costs into their offers. Relevant for investors: for new gas and oil heating systems in rented apartments, landlords will in future bear half of the grid fees, CO2 costs and bio-fuel costs.
What the heating system means for the market value of your property
A modern, efficient heating system remains a strong selling point, especially for detached houses in Berlin's commuter belt. Older systems are no obstacle to a sale, but should be presented openly. A current energy certificate, maintenance records and the year the heating was installed are helpful. Government heating subsidies continue, since 21 July 2026 with a maximum of 28,000 euros in eligible costs, which matters to buyers planning renovations. Sellers who can document the type of heating, consumption data and possible modernisation costs shorten the marketing period and strengthen their negotiating position.
Tip from your real estate agent: check the heating system before selling
Before you sell your house, apartment or plot of land, a sound property valuation that realistically takes the condition of the heating system into account is worthwhile. Our real estate agents in Berlin-Pankow and Wandlitz know the markets in Pankow, Barnim and Oberhavel in detail and offer personal, non-binding advice on market value, documents and sales strategy. You are welcome to arrange an appointment at our office on Wollankstraße in Pankow or on Prenzlauer Chaussee in Wandlitz.