New Zurich tree protection law: felling only with a permit from 1 meter trunk circumference

Zurich is becoming greener – at least if the city council has its way. With the partial revision of the building and zoning regulations (BZO), the city introduced a new regulation on tree preservation in spring 2025. In future, trees with a trunk circumference of more than one meter (measured at a height of one meter above the ground) may only be felled with express permission.

The provision applies to the entire settlement area, with the exception of woodland and predominantly roadside areas. Multi-stemmed trees also fall under the rule: if a trunk measures more than 80 centimetres or the two thickest trunks together have a circumference of more than 120 centimetres, a permit is also required.

A felling permit is only issued if certain conditions are met – for example, if the tree has reached its natural lifespan, there is a danger to people or buildings or the use of a property would be disproportionately restricted. As a rule, replacement planting must be carried out to compensate for the loss of the greenery.

The new regulation is already having an effect today: in accordance with Section 234 PBG, it already applies to current planning applications as part of the so-called “negative prior effect”. This means that developers and owners should adapt their plans to the new requirements at an early stage.

With this tightening, the city of Zurich aims to promote biodiversity, reduce heat pollution in densely built-up areas and improve the quality of life in the long term. For real estate development, this also means new framework conditions – and the opportunity to bring nature and building culture even more into harmony in the future. But there are also unknown, new dangers lurking for developers and construction projects.