Energy renovation in Geneva: obligations, subsidies and works to anticipate

Energy renovation in Geneva has become a central issue for owners of older buildings, villas and rental properties. It is no longer only about comfort or reducing heating costs, but also about cantonal obligations, available subsidies and the long-term value of the property.

In a canton where a significant part of the existing building stock needs to be improved, anticipating the works makes it possible to better control costs, plan administrative procedures and avoid having to act under pressure.

Why renovate a building for energy efficiency in Geneva?

A large part of Geneva’s existing building stock still has significant potential for energy improvement. Older buildings, especially when poorly insulated, can lead to high heating needs, thermal discomfort and significant operating costs.

A well-designed energy renovation can improve indoor comfort, reduce heating needs and modernise the building’s technical installations. It can also help preserve the long-term value of the property, especially in a context where energy requirements are becoming increasingly important.

In Geneva, this is also a regulatory matter. Property owners must take into account the energy performance of their building, particularly through the IDC, the heat expenditure index.

Understanding the IDC in Geneva: the key indicator for energy renovation

The IDC, or heat expenditure index, measures the annual energy consumption for heating and domestic hot water of a building, in relation to its surface area. It is expressed in kWh/m²/year.

This indicator makes it possible to identify the most energy-intensive buildings and determine which measures may be required. For a property owner, the first step is therefore to know the IDC of the building, either through existing available data, with the help of a qualified professional, or through an energy audit.

When the IDC exceeds certain thresholds, improvement measures may be required. These may range from the optimisation of technical installations to a more complete renovation of the building envelope or heating system.

In Geneva, buildings with an IDC above 222 kWh/m²/year are notably concerned by a renovation obligation aimed at reducing their consumption below 125 kWh/m²/year. The framework is also expected to become progressively more demanding: from 2027, the relevant threshold is lowered to 180 kWh/m²/year, then to 153 kWh/m²/year from 2031.

Key point: before starting an energy renovation project, it is essential to know the building’s IDC. This indicator helps identify the applicable obligations, understand the current level of performance and anticipate the works to be planned.

HPE, THPE, Minergie: which standards should be targeted for an energy renovation in Geneva?

In an energy renovation project in Geneva, the HPE-Renovation and THPE-Renovation standards are important references. They help structure the project around a level of energy performance recognised by the canton.

These standards can be achieved in different ways: through a comprehensive renovation, through measures carried out in stages, or through recognised certification such as Minergie-Renovation. The HPE-Renovation standard corresponds to a high level of energy performance. The THPE-Renovation standard targets a more ambitious level, with stricter requirements.

Beyond energy performance itself, these standards may offer several advantages. They help give coherence to the works, improve indoor comfort, reduce energy needs over the long term and, in some cases, provide access to financial incentives or tax advantages.

In Geneva, buildings complying with an HPE or THPE standard may notably benefit from an exemption from the supplementary real estate tax for a defined period, subject to the applicable conditions and the certification issued by the OCEN.

For a property owner, the objective is not necessarily to transform everything in a single phase. A progressive strategy can be considered, provided that the interventions are properly coordinated from the beginning.

Subsidies for energy renovation in Geneva: what should you know?

Geneva provides financial support to property owners for the energy renovation of buildings. These subsidies may apply to different types of measures, depending on the applicable conditions and current technical requirements.

They may support the improvement of the building envelope, the replacement of a fossil fuel heating system, the integration of renewable energy systems or projects aiming for a recognised energy standard such as HPE or THPE.

Subsidies may notably apply to:

• building envelope insulation;
• replacement of the heating system;
• integration of renewable energy systems;
• projects aiming for an HPE or THPE standard.

One point is essential: the subsidy application must be submitted before the works begin. In Geneva, the application must be received by the OCEN at least 14 days before the start of the works concerned. Retroactive applications are not accepted.

Before starting a construction site, it is therefore essential to check which measures are eligible, the available amounts, the technical conditions, the required documents and the applicable deadlines. In some cases, subsidy procedures must also be coordinated with building permit requirements.

Which works should be planned for an energy renovation?

A coherent energy renovation generally begins with a global analysis of the building. Before replacing a heating system, it is important to understand where the main energy losses occur and which interventions will have the greatest impact.

The building envelope is often a central element. Poorly insulated roofs, façades, windows or floors can lead to significant heat losses. Improving the envelope makes it possible to reduce energy needs before correctly sizing a new heating system.

Replacing a fossil fuel installation with a solution using more renewable energy must then be studied according to the building and its context. Depending on the case, possible solutions may include a heat pump, connection to district heating, solar thermal systems, photovoltaic panels, controlled ventilation or optimisation of technical regulation.

The objective is not to add isolated measures, but to build a coherent, progressive strategy that is compatible with the existing building.

Energy renovation of rental buildings in Geneva: what should be anticipated?

For rental buildings, energy renovation must be studied with particular care. The works may reduce tenants’ heating charges, but they also involve questions of financing, rents, subsidies, phasing and the applicable legal framework.

Before starting a project, it is important to assess the energy measures being considered, the available financial support, the possible impact on charges, the rental situation of the building and the necessary administrative procedures.

In this type of project, a preliminary analysis helps define a coherent strategy adapted to the building and its situation. It also helps avoid contradictory decisions, for example between the choice of subsidies, the phasing of the works and the constraints linked to occupied housing.

Why involve an architect from the beginning of an energy renovation?

Energy renovation is not a standard product. It is a project that must bring together several dimensions at once: architecture, technical systems, energy performance, permits, subsidies, budget, planning, building use and long-term real estate value.

An architect can be involved from the early stages to analyse the potential of the property, coordinate the necessary studies, anticipate regulatory constraints and integrate energy requirements into the architectural project.

The architect can help coordinate:

• analysis of the existing building;
• energy objectives;
• permits and subsidies;
• budget and planning;
• architectural quality of the project.

This coordination is particularly important when the building is old, located in a sensitive area or subject to heritage constraints. It helps avoid contradictory interventions and build a coherent strategy between energy performance, architectural quality and real estate value.

Do you have an energy renovation project in Geneva?

Before starting any works, it is essential to understand the energy situation of your building, the applicable obligations, the available subsidies and the real potential of the property.

We support you with the analysis of the existing building, feasibility studies, assessment of transformation potential and definition of the first project orientations.

Contact us to assess the potential of your property and define the first steps of your energy renovation project.

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