Partners   

How to consult a building permit: a practical guide

Published at September 15, 2025 by Bernard
Share
How to consult a building permit: a practical guide

A building site sign has just appeared in your street and you're wondering what's going to be built? Whether you're a curious neighbour or someone directly affected by the project, everyone has the right to consult a planning application. But how do you actually access the file, understand the key information and find out what steps to take if you're not happy with the project? We'll explain it all step by step!

Understanding planning permission and why is it public?

What exactly are we talking about?

Planning permission is an authorisation issued by the town hall. It is compulsory for any new construction or major alteration to an existing building. This authorisation ensures that the project complies with the town's planning regulations. The law makes these documents public in order to guarantee transparency, promote local democracy and enable citizens to monitor development projects.

There are a number of reasons why you might want to consult a planning permission online or at your local town hall:

  • Check that the construction complies with planning regulations;
  • Anticipate the potential impact on your property;
  • Satisfy your curiosity about the development of your neighbourhood.

What valuable information does the file contain?

A planning permission application brings together a number of important documents. The Cerfa form tells you who the applicant is and outlines the project, while the notice describes the nature of the work in more detail. The plans are the most interesting part.

Certain technical data are crucial: the floor area, the height of the building, its footprint, and the materials planned for the walls and roof give you a clear idea of the visual and environmental impact of the future building.

Who can consult a file and how?

Access to planning permission is universal: anyone can apply for it, whether you are a direct neighbour, a local resident or even someone from outside the municipality. It's an application of the right of access to administrative documents, a pillar of our democracy.

Our advice: take advantage of this freedom because you don't have to justify your request or explain your reasons to the town planning department. To analyse the project in more detail, you can request copies of the relevant documents, for a fee set by the town hall.

The practical guide to accessing the file

Consulting the permit at the town hall: the classic method

The first step is to go directly to the planning department of the town hall where the project site is located. This department is generally open at the same times as the town hall, but it is advisable to call ahead to check availability.

Once you are there, formulate your request as clearly as possible, specifying the address of the project or, better still, the permit number. This reference will help officials at the town hall to find the file quickly. To sum up, here are the steps to follow:

  • Go to the town hall planning department;
  • Specify the precise address or permit number;
  • Consult all the documents in the file on site;
  • Ask for photocopies or take authorised photos.

Don't hesitate to take the time to study the documents, particularly the plans, which will give you a clear idea of the project.

Online consultation: more modern, but not always complete

Secondly, you should be aware that the planning process is becoming increasingly digital. Since January 2022, local authorities with more than 3,500 inhabitants have been offering a digital service for submitting and monitoring planning applications. To search for planning permission online, visit the local authority's website or dedicated portals. Some town halls also offer search engines that allow you to filter by address, date or file number.

However, not all files are online, especially older ones. What's more, Internet access sometimes only shows part of the file, so you will have to go to the town hall to obtain all the information.

How do you find the initial information on the ground?

On the other hand, the notice board on the worksite is a valuable and easily accessible source of information. By law, it must be installed as soon as planning permission is granted, and must remain visible throughout the works.

Look at it carefully: it must show the number and date of the permit, the name of the owner, the nature of the project, the surface area of the plot and the authorised floor area. This information will give you a good idea of the scale of the project. Remember to make a note of the permit number displayed on the sign, as this reference will be very useful when requesting the file from the town hall or when you need to find it online without making a mistake.