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Regional service

Flat-Roof Photovoltaics Wallis – Loads, Roof Protection and Mounting

Flat roofs in Canton Wallis offer large PV potential – provided mounting angles, wind loads and maintenance access are aligned before installation. Exactly this planning step decides yield, roof protection and later maintenance.

Clarify before quoting

In Canton Wallis, flat roofs on commercial buildings and multi-family homes represent the largest untapped solar area. Valais relies heavily on solar energy and has integrated MuKEn 2014 into its cantonal energy law. The canton positions itself as the "battery of Switzerland" – the combination of hydropower and solar electricity is to enable year-round renewable supply.

Flat-roof photovoltaics in Wallis requires technically coordinated planning: wind load verification per SIA 261, roof membrane protection and SUVA-compliant fall protection are fixed components of every Vigorek project. The choice between east-west and south orientation is calculated individually based on available roof area, self-consumption profile and ballast requirements.

Prefer to contact us directly? Send your property address, annual electricity consumption (if known) and preferred timing. Roof photos or existing plans help with the initial assessment.

Project profile

Location

Wallis

Service focus

Flat-Roof Photovoltaics

Regional fit

Wallis

Context

How this service works in Wallis in practice.

Wallis comes with its own framework conditions – from incentives and tax treatment to technical requirements. From those, a cleanly managed project flow for your property takes shape.

  1. Service focus

    What matters most for flat roofs

    Flat-roof PV demands more than module rows on paper: wind load verification per SIA 261, roof membrane protection and SUVA-compliant fall protection are part of every Vigorek project scope. For multi-family buildings, commercial properties and industrial halls in Switzerland.

    • Mounting concept based on wind zone, snow load and roof-edge clearance – ballasted or penetrating, with a traceable wind load verification per SIA 261.
    • East-west or south layout matched to available roof area, self-consumption profile and ballast requirements – with realistic yield ranges rather than averages.
    • Protection concept for the roof membrane (separation fleece), maintenance walkways (min. 20 cm foot clearance) and SUVA-compliant fall protection with guardrails from 1 m height.
    • Structurally coordinated planning: PV dead loads, snow and wind loads per SIA 261, and existing roof structures – verified as a requirement, not an option.
  2. Regional framework

    Why this canton shifts the priorities

    Valais: the solar superlatives. ~2,000 sun hours (sunniest canton). Alpine radiation at 2,000m = up to 300 kWh/m²/year (comparable to southern Spain!). Gondosolar: 1,500 solar trees, 18 million kWh/year, 55% winter share. Vineyard agri-PV as innovation.

    • In Canton Wallis, load distribution, wind uplift and roof-skin protection must be resolved before ordering materials.
    • Flat roofs require a different mounting concept than pitched roofs – standard solutions often lead to change orders.
    • Maintenance paths and accessibility determine the long-term operating costs of the system.
  3. Project logic

    How structure and roof membrane are planned together

    The order records these steps, responsibilities and required documents. Outstanding assessments belong in the schedule before work begins.

    • Roof inspection assessing statics, roof skin and existing installations.
    • Mounting geometry aligned with wind zone, tilt angle and usage concept.
    • Protection concept for roof skin, walkways and future maintenance access.

Regional context

Flat-Roof Photovoltaics in Wallis: what matters here

In Canton Wallis, cantonal rules, the responsible grid operator and local permit procedures shape how a project is planned and delivered. The points below show what really matters before quoting, installation and handover.

Regional starting point
In Canton Wallis, incentives, grid operators and permit procedures change the priorities for this service.
Service core
Flat-roof PV is not a standard grid: wind load, ballast, roof membrane protection, walkways and later access define the design.
Grid & registration
For Canton Wallis, grid operators such as EnBAG, EW Obergoms, metering concept and commissioning are aligned early.
Decision reason
In Canton Wallis, load distribution, wind uplift and roof-skin protection must be resolved before ordering materials.
Execution
Roof inspection assessing statics, roof skin and existing installations.
Economic frame
Feed-in tariff and self-consumption are matched to the property; in the canton, EnBAG 2026, unter 80 kVA: 14.00 Rp./kWh Sommer / 6.5 Rp./kWh Winter, exkl. MWST; zusätzlich 1.5 Rp./kWh HKN bei Übertragung. Andere Walliser Netzgebiete: Tarif beim zuständigen VNB prüfen. is one relevant reference point.

Cantonal framework

Which cantonal framework shapes the project in Wallis.

The technical service stays the same, but the project frame changes with the canton. That is exactly where incentives, tax treatment and MuKEn requirements become strategically relevant.

Local context

Wallis sets the economic pace for this service.

Valais has the highest solar irradiation in Switzerland – Sion counts over 2,100 sunshine hours per year. Alpine systems like those on the Muttsee dam wall or at Gornergrat demonstrate the enormous potential for winter electricity production in the Valais Alps.

Tax and subsidy logic

In Valais, solar systems are fully tax-deductible as energy-saving investments. The high solar irradiation ensures short payback periods of often only 8–10 years – the tax deduction further accelerates this. Solar obligation for new buildings: under federal Art. 45a EnG, new buildings with a chargeable floor area over 300 m² must install a solar system (photovoltaic or solar-thermal) on the roof or façade (for permits filed from 1.1.2023); the cantons set the exceptions and the specific minimum area. In the canton of Valais the area of the solar panels or thermal collectors must cover at least 40% of the chargeable building area (cantonal energy ordinance, formerly Art. 28a VREN, kEnV since 1.1.2025). In addition, the cantonal energy law (kEnG, in force since 1.1.2025) introduces a self-generation obligation for new buildings: at least 20 W/m² of energy reference area, with no power above 30 kW being required. Mainly thermal subsidies at cantonal level.

Permits and energy law

Solar obligation: federal law (Art. 45a EnG) requires a solar system on the roof or façade of new buildings with a chargeable floor area over 300 m² (for permits filed from 1.1.2023) — the cantons set the specific minimum area; in Valais at least 40% of the chargeable building area (cantonal energy ordinance, formerly Art. 28a VREN, kEnV since 1.1.2025). In addition, a cantonal self-generation obligation applies since 1.1.2025 (at least 20 W/m² of energy reference area, no requirement above 30 kW). Gondosolar and large alpine systems: Solarexpress procedure. Vineyard agri-PV: flexible regulations. Normal notification procedure for standard systems. Valais relies heavily on solar energy and has integrated MuKEn 2014 into its cantonal energy law. The canton positions itself as the "battery of Switzerland" – the combination of hydropower and solar electricity is to enable year-round renewable supply.

Market signal and location

Valais: the solar superlatives. ~2,000 sun hours (sunniest canton). Alpine radiation at 2,000m = up to 300 kWh/m²/year (comparable to southern Spain!). Gondosolar: 1,500 solar trees, 18 million kWh/year, 55% winter share. Vineyard agri-PV as innovation. Valais offers special subsidies and simplified approval procedures for alpine solar systems. Besides the Pronovo one-time payment, the canton subsidizes storage solutions and large projects. The Service for Energy and Hydropower (DEWK) provides comprehensive consulting.

Sun hours/year

~2'000h SONNIGSTER Kanton der Schweiz!