Energy efficiency increasingly affects renovation budgets, mortgage terms and resale value when buying a Swiss house. According to the FSO, Switzerland had around 1.8 million residential buildings in 2023; oil heating accounted for about 39 % of residential buildings and gas for about 17 %.
The GEAK, known in English as the Cantonal Energy Certificate for Buildings, rates properties from A to G and distinguishes between the building envelope and overall energy efficiency. Class A indicates a very efficient envelope and low energy demand, while class G typically points to an unrenovated property with substantial heat loss. The certificate does not use one single kWh threshold for every house, because building category, use and energy reference area are taken into account. For buyers, a GEAK Plus is more useful than a basic certificate because it sets out renovation packages, cost estimates and savings, and for a single-family house it often costs around CHF 1'200 to CHF 2'000.
Energy rules are cantonal, so a buyer must check the exact law in the canton where the property is located. Canton Zurich, for example, generally requires existing central electric resistance heating systems to be replaced by 2030 and has applied stricter rules for replacing fossil heating since 2022. Cantons such as Basel-Stadt, Geneva and Vaud have also introduced tighter requirements for oil and gas systems, permits or minimum renewable-energy shares. A house with GEAK E, F or G can therefore imply future renovation costs of CHF 50'000 to more than CHF 200'000, depending on the canton and building condition.
An air-to-water heat pump for a single-family house typically costs about CHF 35'000 to CHF 55'000, while a ground-source system with boreholes often reaches CHF 55'000 to CHF 85'000. The economics become particularly relevant where the current consumption is around 1'500 to 2'500 litres of heating oil per year or where the heat load is roughly 8 to 10 kW or more. With a seasonal performance factor of 3.0 to 4.0, a heat pump producing 18'000 kWh of heat uses about 4'500 to 6'000 kWh of electricity. Depending on electricity tariffs, oil prices and the CO₂ levy, annual energy costs can fall by roughly CHF 1'000 to CHF 2'500 compared with oil or gas.
The Buildings Programme run by the Confederation and the cantons is financed partly by the CO₂ levy, which has been CHF 120 per tonne of CO₂ since 2022. The programme reported nationwide subsidy payments of around CHF 528 million in 2023. Typical grants are about CHF 40 to CHF 80 per m² of insulated component area, CHF 3'000 to CHF 10'000 for replacing a heating system and additional cantonal bonuses for improving the GEAK rating. Under FTA practice, value-preserving energy-saving investments may be deducted for direct federal tax purposes, and since 2020 certain energy-related costs connected with replacement buildings can be carried forward over up to 3 tax periods.
Market value is influenced not only by location and land value, but also by the capital expenditure needed for the envelope, heating and hot water system. A house with GEAK F and a 25-year-old oil boiler will often face a larger valuation adjustment than a comparable property with GEAK B and a heat pump. Swiss banks commonly offer green mortgage discounts of about 0.10 to 0.25 percentage points, usually for Minergie, GEAK A or GEAK B properties. FINMA and the Swiss Bankers Association do not prescribe a uniform discount, but the SBA self-regulation requires energy efficiency and value preservation to be addressed in mortgage advice for owner-occupied single-family houses.
Before signing, buyers should request the current GEAK, a GEAK Plus or at least the energy bills for the last 3 years. Key points are the year of construction, energy reference area, insulation standard, heating age, tank condition, chimney requirements and whether a heat pump is permitted under noise, groundwater or borehole rules. In many cantons, subsidy applications must be filed before work starts, otherwise grants worth several thousand francs can be lost. The financing plan should test a renovation reserve of at least CHF 50'000 to CHF 150'000, because banks often assess affordability using a notional mortgage rate of around 5 %.