Subsidies and tax for heating renovation: what applies to underfloor heating?
As a rule, there are no direct subsidies for renovating existing underfloor heating. As a value-preserving measure, however, it is relevant for tax purposes: maintenance costs for properties held as private assets can currently, in principle, be deducted from taxable income; for owner-occupied property, based on the current legal position, this applies for the last time for the 2028 tax year. In Switzerland, subsidies are mainly available for replacing fossil-fuel or electric heating with renewable systems and for energy-related improvements to the building envelope. Which measures and contributions apply is decided by the canton in which the building is located.
According to information as of 24 September 2026, cleaning, repairing or internally renovating existing underfloor heating is not normally a subsidised measure in its own right. It can nevertheless be technically important if a heat pump is planned and the existing heat distribution first needs to be inspected or repaired. Subsidies, technical necessity and tax-related value preservation are therefore three different questions.
What renovation means for tax purposes
Renovating existing underfloor heating serves to preserve the value of the property. Value-preserving maintenance costs for properties held as private assets can currently, in principle, be deducted from taxable income for both federal and cantonal tax. In addition, certain investments in energy saving and renewable energy may be deductible. Subsidies reduce the portion you bear yourself, and therefore the deductible portion. Whether a specific piece of work counts as value-preserving maintenance, a value-enhancing investment or an energy-related measure is assessed by the competent tax authority; you should therefore clarify the classification with the tax authority or a fiduciary specialist in advance.
The Federal Council has brought the reform of residential property taxation into force with effect from 1 January 2029. For owner-occupied property, the imputed rental value will then be abolished, along with the deductions for maintenance costs at federal, cantonal and municipal level. For direct federal tax, the deductions for investments in energy saving and environmental protection will also be abolished; the cantons may continue such energy deductions for a limited period. For let or leased properties, the deduction for maintenance costs remains in place. This overview does not replace individual tax advice.
The most important principle before construction starts
For the subsidy measures covered here, the application must as a rule be submitted before construction starts. The current conditions of the relevant programme and canton are decisive. Do not start the work or make any purchases that could jeopardise the subsidy until the competent body has confirmed the permissible procedure. A quote alone is not a subsidy commitment.
What the Buildings Programme (Das Gebäudeprogramm) supports
Depending on the canton, the Buildings Programme run jointly by the Confederation and the cantons supports thermal insulation, renewable heating systems, connections to district heating networks and comprehensive energy-related renovations, among other things. For heat pumps, the conditions vary according to output, heat source, the existing heating system and location. Each canton decides which measures it offers and on what terms.
For reliable project planning, you should therefore use the current cantonal programme page and the specific application portal rather than general tables or older information sheets.
Is renovating existing underfloor heating subsidised?
As a rule, no. The official subsidy measures are primarily aimed at heat generation, the building envelope and defined comprehensive renovations. Cleaning, repairing or internally renovating existing hydronic underfloor heating is not normally listed as a separate subsidy measure.
One important exception must not be confused with renovating existing underfloor heating: under certain conditions, the national incentive programme (Impulsprogramm) supports the replacement of decentralised oil, natural gas or electric resistance heating systems that have no hydronic heat distribution system. In this case, the first-time installation of hydronic heat distribution can form part of the subsidised conversion. The competent canton confirms whether a specific project meets the conditions.
How to find the programmes for your building
Enter the postcode of the building's location on energiefranken.ch and collect the available programmes.
Cross-check the results on the official energy website of the competent canton.
Clarify the project, the existing heating system and the planned measures with the cantonal energy office or a qualified energy adviser.
Submit the complete subsidy application before construction starts and wait for the canton's response.
Only then commission services or start work, insofar as the subsidy conditions allow.
Official offices in your canton
We renovate underfloor heating throughout Switzerland. Subsidy matters are always the responsibility of the canton in which the building is located. The Conference of Cantonal Energy Directors (EnDK) lists the energy offices of all 26 cantons in its directory: energiehub-gebaeude.ch/kontakte/kantonale-energiefachstellen.
To see which programmes apply at your location, enter your postcode on energiefranken.ch.
SwissEnergy's free «renewable heating» consultation (Impulsberatung)
The «renewable heating» consultation (Impulsberatung) is a service of the federal SwissEnergy programme and is carried out by approved specialists. It is free and without obligation if the subsidy conditions are met and the heat generator serving as the main heating system is more than ten years old. The consultation includes an on-site assessment and a recommendation with an initial cost estimate, as well as information on subsidies and tax deductions.
This consultation assesses the replacement of the heating system. It does not replace the technical condition analysis of old underfloor heating. The two assessments answer different questions and can usefully complement each other.
What we can and cannot clarify
We inspect and renovate existing underfloor heating. In doing so, we clarify whether the heat distribution is suitable for the planned overall system and whether any measures are needed on heating circuits or components. The binding subsidy assessment, submission of the application, tax advice and planning of the new heat generator are the responsibility of the competent cantonal offices and qualified specialists.
Frequently asked questions
Next step
If you are planning to replace your heating system and do not know the condition of your existing underfloor heating, we will assess your situation in a free initial phone consultation. If a detailed inspection makes sense, this is followed by our on-site condition analysis, which can be carried out for a few hundred francs. Subsidy applications, heating planning and tax questions are dealt with separately with the bodies responsible for them.
Subsidy and tax information as of 24 September 2026. Programmes and conditions may change. The official bodies at the time of the project are authoritative.