Construction of a terrace: do I need to apply for a work or a permit?

Do you want to enjoy the outside of your home and set up a terrace? But do you know if you are required to apply for a building permit? Do you just need to declare your future work? Or do you not need to start an administrative process? The construction of a terrace is subject to formalities. Depending on the surface of your future terrace and its footprint, you may be asked for a prior declaration, a building permit or nothing at all.

What type of patio are you considering?

  • An uncovered single-storey terrace
  • A single storey terrace with awning
  • A raised terrace in relation to your land
  • A terrace overlooking the ground floor of your house
  • A roof terrace
  • Etc.

The SHON and the SHOB replaced by the footprint and the floor area

About ten years ago, there was talk of SHON or Surface Hors d’Oeuvre Nette and SHOB Surface Hors d’Oeuvre Brute. These have been removed in favor of two new measures: the footprint and the floor area. The footprint is the vertical projection of the volume of the construction while the floor area is the sum of the areas of all the levels built. These are the two measures to be taken and calculated for the application for a building permit or a prior declaration of work.

What type of terrace does not require prior authorization?

Three types of terraces are not subject to authorization. These are the smallest, those that are less than five square meters. Then those which are carried out under an existing awning. Finally, those which are on one level and do not require any elevation: these are the most common. If you are not very familiar with what an elevation is, consult the town planning department of your municipality before starting your work.

What type of terraces are subject to authorization?

On the other hand, terraces requiring an elevation require a prior declaration or a building permit depending on the surface. The raised terraces of more than 60 centimeters are subjected either to prior declaration or to building permit according to their surface.

Terraces subject to prior declaration

If your patio is scheduled to not exceed 20 square meters of floor space or footprint, then you will need to make a prior declaration.
What steps should be taken for a prior declaration? The work declaration is a file to be completed and submitted to the town hall of your municipality. This must know if you are preparing to respect the current town planning rules in order to be able to validate your project. You will have to look at the Local Urban Plan of your city in order to locate your land there and to see the regulations which are related to it. Then, you will need to complete a form with information about your patio project. The eight mandatory documents are as follows:

  • The situation plan
  • The ground plan
  • The cutting plane
  • The facade and roof plan
  • A representation of your terrace
  • The graphic document
  • Close up photos
  • Pictures from afar

Terraces subject to building permits

If your patio is to exceed 20 square meters of floor space or footprint, then you will need to apply for a building permit.
What approach to take for a building permit? Here again, before obtaining a building permit, it is imperative to refer to the Local Urban Planning Plan of your municipality and then inquire about the requirements requested. Check in particular that you are not in a specific area such as those near a historic building. As with the prior declaration of work, a file of several documents will be requested. You will need to present:

  • A situation plan
  • A ground plan
  • A cutting plane
  • A descriptive notice
  • A plan of facades and roofs
  • A graphic document
  • A photo in a close environment
  • A photo in a distant environment

Additional documents may be added to your file depending on the characteristics and location of your project.

A complex assessment

It is sometimes difficult to know in which framework your project fits. This is why it may be wise to contact the town hall of your municipality so that they can tell you more about the subject. Because some circulars can be made much more opaque to decipher than expected. And the footprint is not necessarily the most obvious to calculate. Get information or advice from experts or professionals in the field.