Building zone and non-building zone: the differences
The building zone
The Spatial Planning Act (art. 15) defines the building zone as land suitable for construction that is already largely built up, or whose need for the next fifteen years is demonstrated, and which will be serviced within that period. A plot classified in the building zone can in principle be built on in accordance with the use provided for by the municipal zoning plan (residential, business, mixed).
Outside the building zone
A plot located outside the building zone (agricultural zone, forest zone, protected zone) is in principle not buildable, as the Spatial Planning Act aims to limit urban sprawl and preserve agricultural land and natural areas from scattered construction.
Possible exceptions
Art. 24 SPA exceptionally allows, under strict conditions, an exceptional authorisation for construction outside the building zone whose location is required by its purpose (such as certain agricultural buildings) and which does not conflict with any overriding interest. These exceptions are interpreted restrictively by authorities and courts.
The impact on the value and use of a plot
A plot's zoning (buildable or not) has a decisive impact on its value and the concrete possibilities for using it: before any project or purchase, it is essential to precisely check the applicable regime with the cantonal or municipal spatial planning department, with the municipal zoning plan being authoritative.
Frequently asked questions
Can I build on a plot classified outside the building zone?
In principle no, except for an exceptional authorisation under art. 24 SPA, reserved for construction whose location is required by its purpose and which does not conflict with any overriding interest.
How do I find out if my plot is in the building zone?
By consulting the zoning plan of the municipality where the plot is located, available from the municipal or cantonal spatial planning department.
Can a building zone be changed later?
Yes, zoning plans can be revised by the competent municipal and cantonal authorities, in compliance with the federal principles of the Spatial Planning Act, which can change a plot's buildable status over time.