Anyone wishing to install solar panels on their own roof should familiarise themselves with the legal framework at an early stage. When is it sufficient to simply notify the local council – and when is planning permission actually required?
First, Clarify: Is the Plot of Land Within the Building Zone?
As with any building project, the first step is to clarify whether the plot of land on which the solar installation is to be built is within or outside the building zone. This distinction is crucial, as stricter regulations apply outside building zones and a formal planning permission process is more often required.
Federal Law: When Solar Installations Are Exempt From Planning Permission
The key provisions at national level are set out in the Spatial Planning Act (RPG) and the Spatial Planning Ordinance (RPV). As a general rule, solar installations on roofs in building and agricultural zones do not require planning permission if they are sufficiently integrated into the surroundings. In such cases, a notification to the relevant authority is sufficient.
Article 32a of the Spatial Planning Ordinance (RPV) defines the conditions under which solar installations on roofs are considered ‘sufficiently integrated’ within the meaning of Article 18a of the Spatial Planning Act (RPG) and are therefore subject to notification but do not require planning permission. This is particularly the case where the installations protrude only slightly above the roof surface, do not extend beyond the roof surface when viewed from above, are designed to minimise reflection and are arranged compactly.
Solar installations on flat roofs are also considered sufficiently adapted if they protrude no more than one metre above the upper edge of the roof, are set back sufficiently from the roof edge so that they are not visible from below at a viewing angle of 45 degrees, and are also designed to minimise reflection in accordance with the state of the art.
Specific Provisions in the Canton of Lucerne
In addition to federal law, the Canton of Lucerne applies additional provisions set out in the Planning and Building Ordinance (PBV). In particular, the size of the installation is a decisive factor.
Solar installations with an area of less than 20 m² are, in principle, neither subject to notification nor requiring authorisation in building and agricultural zones, provided they are sufficiently adapted to the building envelope and the surrounding area. However, this does not apply in areas subject to townscape protection or in the case of listed buildings worthy of protection.
Systems with an area of more than 20 m² are subject to notification, provided the requirements under federal law are met. The notification must be submitted to the relevant local authority at least 20 days before work commences.
If the requirements under federal law are not met, or if there are conflicting public or private interests, a standard building permit procedure is required. Under certain conditions, however, the application may be assessed and approved via a simplified procedure.
Special Rules for Listed Buildings
If a building is listed or subject to townscape protection, stricter requirements apply. In such cases, a standard planning permission is usually required. The local planning authority will assess, in particular, whether the solar installation would adversely affect the appearance of the building or its surroundings, and will seek the approval of the cantonal heritage conservation authority. If the building or installation is located outside the building zone, approval from the Department of Spatial Planning and Economic Affairs is also required.
Should you have any questions regarding building law or planning permission procedures, the attorneys-at-law at Pilatushof AG will be happy to assist you.
