Change of use: why a building application can be required although nothing is being built
The commonest misconception in short-term letting: that anyone who does not renovate needs no permit. Building law sees it differently.
What is a change of use?
A change of use occurs when a building or part of a building is used differently from what was permitted — living instead of commerce, or the reverse. It requires a building permit even where no construction work is involved. For the change to permanent commercial short-term letting, the City of Zurich expressly requires a building application and a declaration of the type of residential use.
Why it applies without a building site
A building permit allows not merely a building but a particular use of that building. Change the use and you depart from the permit — even if no tradesman turns up. Building law attaches to the type of use, not to construction activity.
The reason is obvious once you have seen it: a different use has different effects on the surroundings. Traffic, hours of noise, parking demand, number of people. The zoning ordinance regulates precisely those effects — and it can only do so if a change in the type of use becomes visible at all.
What the City of Zurich requires
The city names two duties expressly. First, a duty to report permanent commercial uses. Second, a building application for changes of use — and that also where no construction work is involved. Once the rules take legal effect, applicants must declare the type of residential use in the building application.
Where the line runs between occasional letting and permanent commercial use is a question of the individual case. It cannot be read off a number of nights, and no platform answers it. The municipal building authority is responsible, and the answer costs nothing.
Frequently asked questions
- Do I need a building application if I am not renovating?
- For a change of use to permanent commercial short-term letting, yes — according to the City of Zurich even where no construction work is involved. Building law attaches to the type of use, not to construction activity. For the individual case the building authority is the body to ask.
- From when does letting count as a change of use?
- When living turns into permanent commercial use. There is no fixed number of nights for it; what counts is permanence and commercial character in the individual case. Anyone letting their own flat while away does not change the type of use — anyone letting it year-round to changing guests very much does.
- What happens if I do not report the change of use?
- It remains a departure from the building permit, and that does not lapse merely because it goes unnoticed. If it does come to light — through a neighbour's complaint, an inspection or a later building application — the authority can require restoration of the lawful state. Asking beforehand is cheaper than being told afterwards.
Your question is not answered?
Send it to us — we answer from practice, in writing, within one working day.