Valais

Renovating in Martigny: A comprehensive guide for your property

Renovating your property in Martigny requires a precise understanding of local climatic, energy, and heritage specificities. This guide assists you in your projects to optimize the value and performance of your building.

471 m

Altitude

12.5 °C

Mean temperature

50

Frost days

1'252 kWh/kWc

Estimated solar yield

Local context: climate and built environment

Located at an altitude of 471 meters, Martigny presents climatic conditions influenced by its alpine location.5 °C and about 50 frost days per year, heating needs are real, calculated at 2,482 Kj/year (20/12 °C).2 °C. Sunshine is a major asset for the region, with global horizontal irradiation of 1,423 kWh/m²/year.

The real estate stock of Martigny, although diverse, faces the challenges of aging structures. The City is currently working on developing a complete inventory of its built heritage, including ISOS perimeters and historic zones.

This process, coupled with the revision of the Zoning Plan (PAZ) and the Construction and Zoning Regulation (RCCZ) expected by 2025, will regulate interventions on facades and roofs to preserve the local architectural identity while allowing for necessary energy transitions.

Priorities for energy renovation

The absolute priority for owners in Martigny is the optimization of the building's thermal envelope. Given winter temperature variations, facade insulation is a key measure to reduce energy demand. In addition, replacing old windows with high thermal performance models is highly recommended.

These works help limit thermal bridges and sustainably improve interior comfort.

Once insulation is optimized, the transition to renewable heat production systems should be considered. Aid from the Building Program, accessible in Valais, specifically supports these global renovation measures.

It is crucial to plan these interventions in a coherent logic, prioritizing passive actions (insulation) before sizing a new heating system. This approach allows not only for achieving better energy efficiency but also for benefiting from cantonal grants for the building envelope.

Heating and district heating

Martigny has a district heating network (CAD) developed for over 40 years by Sinergy. This network represents a structuring solution for owners. In 2025, the CAD was 51% powered by renewable energy, including wood from regional forests and biogas from the treatment plant, the rest being provided by natural gas.

The goal is ambitious : to reach 80% renewable energy by early 2027, thanks to the installation of a new wood boiler and a second silo. Deployment continues in many neighborhoods.

For those who cannot connect to the CAD, installing a heat pump is an alternative encouraged in Valais. Owners can benefit from cantonal aid, often in the form of flat-rate contributions per kW. It is essential to inquire with the competent energy department or via the Building Program website for the applicable rates.

8 °fH), an advantageous factor for the longevity of thermal installations.

Authorizations and heritage compliance

Renovation in Martigny takes place within an evolving regulatory framework. The City is currently conducting an inventory of its built heritage, including ISOS perimeters and historic zones.

If your property is located in these sectors, specific constraints may apply, especially for modifications visible from the public space. The approval of the PAZ and RCCZ expected by 2025 will aim to harmonize these rules for protecting and enhancing significant buildings.

Before undertaking work that alters the external appearance (facade insulation, installation of solar panels, changing visible windows), it is imperative to consult the municipal authorities. The Municipality evaluates each project to ensure architectural coherence.

There are no general guidelines fixed in the provided sources for solar installation, which implies that each case is studied according to its zone.

Early planning and consultation with the urban planning department help avoid refusals and integrate your energy improvement measures while respecting the historical character of Martigny.

Financial aid and taxation

Owners in Martigny can apply for several types of aid. At the federal and cantonal level, the Building Program offers contributions for facade insulation, window replacement as part of a comprehensive renovation, as well as for solar thermal systems.

For heat pumps, Valais grants flat-rate aid based on the installed technology. Regarding photovoltaics, a one-off remuneration is available via the federal Pronovo system, sometimes supplemented by specific municipal premiums.

1 since 2023 and remains stable for 2025. It is useful to recall that investments intended for energy saving and environmental protection can, in many cases, be deducted from taxable income. To maximize these benefits, it is recommended to precisely list maintenance work versus energy value-added work.

Consult the Building Program website for the exact eligibility conditions and do not sign any contractor agreement before having received a grant confirmation for your renovation projects.

Planning and selecting contractors

Succeeding in your renovation in Martigny requires rigorous planning. The first step is to establish an energy audit to prioritize work. Whether you are considering a kitchen renovation, changing floors, or installing solar panels, it is better to group interventions to optimize costs and subsidy applications.

Once your needs are defined, request several quotes from recognized local companies.

During selection, verify the qualifications of the artisans, particularly their specialization in Minergie standards or renewable heating systems. Require detailed quotes distinguishing between material and labor costs.

Coordination between different trades is crucial, especially in the context of a comprehensive energy retrofit. A general contractor or an architect can facilitate this project management.

Also, ensure that each company confirms its ability to meet deadlines and municipal heritage requirements, particularly in the city's protected sectors.

Local data in detail

Heating and energy

A well-oriented solar PV system yields roughly 1'252 kWh per kWp per year here.[5]

Permits and heritage

ISOS inventory. yes

Protected areas. yes[2]

Water quality

Local housing stock

Choose your works in Martigny

Climate data for Martigny

Altitude
471 m[6]
Heating degree days
2'482 Kj/an (20/12 °C)[7]
Frost days
50 jours/an[8]
Solar irradiation
1'423 kWh/m²/an (horizontal)[9]
Winter design temperature
-8.2 °C (1er percentile des minimales)[10]
Mean temperature
12.5 °C[11]
Estimated solar yield
1'252 kWh/kWc/an (toit ~30° sud, PR 0.8, estimation)[5]

Nearby municipalities : Sion · Monthey · Sierre · Brigue-Glis

Frequently asked questions

What aid is available for insulating my facade in Martigny?

In Valais, the Building Program grants financial contributions per m² for building envelope insulation according to the performance requirements achieved.

Is the district heating network mandatory in Martigny?

No, connection is not automatic, but it is strongly encouraged by Sinergy in served neighborhoods as an alternative to fossil fuels.

Do I need a permit to install solar panels?

Yes, consultation is recommended because Martigny protects its built heritage. Each project is evaluated according to its zone and visual integration.

What is the water hardness in Martigny for my appliances?

The water supplied by Sinergy is classified as very soft, with a hardness of 2.8 °fH, which is very favorable for your thermal installations.

Can subsidies be combined with tax deductions?

Yes, energy-saving investments can often be deducted from taxable income, in addition to the subsidies received.

Where can I find information on municipal premiums?

Inquire directly with the Municipality or on the Valais aid portal to identify the premiums available for your neighborhood.

Sources

  1. [1] sinergy.ch
  2. [2] Martigny.ch
  3. [3] QUALITÉ DE L'EAU 2023 - Sinergy
  4. [4] — · estimate
  5. [5] Open-Meteo Historical Weather API (réanalyse ERA5, moyenne 2015-2024) · estimate
  6. [6] swisstopo – service d'altitude (MNT)
  7. [7] Open-Meteo Historical Weather API (réanalyse ERA5, moyenne 2015-2024)
  8. [8] Open-Meteo Historical Weather API (réanalyse ERA5, moyenne 2015-2024)
  9. [9] Open-Meteo Historical Weather API (réanalyse ERA5, moyenne 2015-2024)
  10. [10] Open-Meteo Historical Weather API (réanalyse ERA5, moyenne 2015-2024)
  11. [11] Open-Meteo Historical Weather API (réanalyse ERA5, moyenne 2015-2024)