Background
#The solar duty for roof renovations in Schaffhausen has applied since 1 January 2026 when the roof membrane is comprehensively renovated and the attributable building area is at least 300 m².
Section 26h of the Energy Ordinance then requires suitable roof areas with at least 85% global irradiation (Annex 7) to be used for on-site electricity generation. For buildings with an energy reference area, the solar-electricity system must provide at least 30 W/m² of energy reference area; buildings without an energy reference area must cover at least 60% of the roof, with solar thermal systems counted.
Minor repairs and maintenance work on roof areas are not covered by this rule, while protected objects and protection zones require additional assessment under the Building Act and the solar guidelines. The Schaffhausen energy office and cantonal geoportal support the preliminary check; the specific classification remains object-specific.
For your roof
New build: size the system right
For solar obligations what counts is output per area. With your address or postcode we size output, yield and cost for your new build.
Free and non-binding · no unsolicited calls
Rather talk directly? +41 78 615 90 58
What roof and planning dictate
#The trigger is the roof membrane, not the label “renovation”: section 16a(7) EnerV describes a comprehensive roof renovation as the large-scale replacement or repair of the roof membrane. Minor repairs and maintenance work on roof areas are expressly outside this rule.
The size threshold is set out in section 26h(1) EnerV: the rule applies from an attributable building area of 300 m² and to roof areas with at least 85% global irradiation under Annex 7. The 300 m² is not a blanket module or roof-area figure; it must be assessed for the specific building.
For a building with an energy reference area, section 26h(2)(1) EnerV requires at least 30 W of solar-electricity capacity per m² of energy reference area. This affects module area, inverter design and the roof quote; a rough estimate based on living area does not replace the project-specific reference area.
If a building has no energy reference area, section 26h(2)(2) EnerV requires at least 60% of the roof area to be covered. Areas used for solar thermal hot-water production count, so the technical choice between solar electricity and solar thermal must be visible in the roof design.
The duty is not automatically tied to a building permit: section 2(2) EnerV requires the energy provisions to be met even when the measure does not require a building permit. A notification procedure or permit exemption therefore does not prove that section 26h is irrelevant.
Protection status changes the route: for solar systems on cultural or natural monuments of cantonal or national importance, the Schaffhausen planning guide refers to Art. 18a(3) RPG and Art. 32b RPV; Art. 54(4) BauG requires a building permit there. The geoportal procedure map and the Energy and Design specialist team should be involved before detailed planning.
The process in six steps
#Tick off for your project
Classify the project
describe whether the roof membrane will be replaced or repaired on a large scale, and record the distinction from repair and maintenance work under section 16a(7) EnerV. The actual measure matters, not the label used in the quote.
Check building and roof area
determine the attributable building area of 300 m² under section 26h EnerV and identify suitable roof areas with at least 85% global irradiation under Annex 7. Roof plans, rooftop structures and shading belong in the same preliminary assessment.
Calculate the minimum size
where an energy reference area exists, dimension the system to at least 30 W/m² of EFA. Without an energy reference area, plan for at least 60% roof coverage; solar thermal may be counted under section 26h(2)(2) EnerV.
Plan roof and system together
translate the 30 W/m² or 60% requirement into a module and mounting concept before the roof membrane is ordered or opened. This keeps the structure, penetrations, cable routes and solar-thermal/PV decision under section 26h consistent.
Check the procedure
use the Schaffhausen geoportal procedure map for the property and compare its protection status with Art. 54(4) BauG, Art. 18a(3) RPG and the planning guide. For a protected object or protection zone, clarify the building permit before construction.
Secure documents and responsibility
keep the roof layout, building area, global irradiation, EFA or area calculation and protection status together with the quote. The Energy and Design specialist team is available through the Schaffhausen energy office for the cantonal assessment; the binding decision is made for the specific property.
Checked for your roof, not just read up on
New build: size the system right
For solar obligations what counts is output per area. With your address or postcode we size output, yield and cost for your new build.
Free and non-binding · no unsolicited calls
Rather talk directly? +41 78 615 90 58
Frequently asked questions
#Sources
#The responsible authorities are decisive. Always verify binding details – amounts, deadlines and conditions – for your specific property against the current status of the respective authority.