Your roof: Lens
For a detached house, check roof condition, shading and electrical capacity before signing. A single owner’s decision still requires a technical roof survey.
In all cases, the useful surface area is almost always less than the gross surface area announced. Skylights, chimneys, setbacks, shading and future maintenance needs must be integrated before talking about final power.
Define included and excluded work during the technical survey. Value surplus using the confirmed export contract, with guarantees of origin accounted for separately.
Exposure and access: Lens
Request a survey of nearby shading and the horizon, with monthly generation estimates. Compare options for your building using the same weather data and loss assumptions.
Measure usable roof area with obstacles and required clearances included. Agree on tests, inspections and documents to be provided at handover.
Full cost and grants: Lens
The displayed scenario uses an indicative installed cost for 8 kWp. A quote must specify equipment, roofing and electrical work, connection, inspections and fees before deducting confirmed grants.
Programmes depend on the municipality and available funds. Obtain written confirmation of amounts, timing, limits and combined support for your address before including them in the budget.
Check the simultaneous consumption used to estimate avoided electricity purchases. Distinguish avoided purchase costs from the tariff paid for exported surplus.
Output must be assessed for the actual roof, its orientation, shading and condition. Tariffs depend on the grid, product and contract; a cantonal average does not replace your bill.
Building procedures: Lens
Request plans, equipment references and service boundaries before accepting a price. Agree on tests, inspections and documents to be provided at handover.
A serious estimate specifies who prepares the announcement, who manages the connection, who follows the administrative back and forth and how any comments are absorbed into the planning.
In Valais, residential photovoltaics first go through Pronovo; Any municipal aid or other energy measures must be confirmed before signature.
Request a technical site survey before relying on a sales estimate. Keep the simulation assumptions so results can be compared after commissioning.