Plans, building permit: what price?
As a general rule, carrying out important works such as the construction of a house, its extension, or the transformation of its use, are subject to a request for a building permit. If a building permit application is, in itself, free, this is generally accompanied by costs linked to the intervention of professionals, and involves the payment of local taxes.
Since the creation of a building permit file is particularly long and tedious, it is common to use the services of an architect or a building designer to be accompanied in this task. Note, moreover, that the use of an architect becomes compulsory as soon as the planned construction exceeds 150 m² or when the enlargement to be carried out carries the total surface of the building beyond 150 m².
Go through an architect for his building permit
When you want help with your building permit application, the first reflex is usually to turn to an architect. The price to consider for the management of your building permit file then depends on the complexity of the mission that you will entrust to it:
- mission limited to the design of the project and the realization of the building permit file: count around 50 € HT / m², with a minimum price of 1,500 € HT
- complete mission, from the design of the project (including the building permit) to its delivery, including the monitoring of works: from 8 to 15% of the total amount HT of the works.
More info: Prize for an architect’s mission
Call on an independent designer
If the floor area created by your construction is less than 150 m² or the surface of the building after enlargement remains less than 150 m², it is quite possible to have recourse to a designer in building or architecture. This will be responsible in particular for carrying out the plans to be attached to your building permit application. For the complete assembly of a building permit file, the designer will generally charge you either a package between 1,000 and 2,000 € HT, or a percentage on the total amount of the work (in general, around 3.5% ).
You will have understood it: unlike the mission of an architect, which involves real support and expert advice, that of a building designer is generally limited to drawing up the plans for the future work.
Costs related to the compulsory thermal study
Your building permit file must include a certificate to take into account the thermal regulations in force. To obtain this document, it is necessary to call on a thermal studies office, which will rely on the plans and technical characteristics of your project to calculate the Bbio coefficient (bioclimatic need) of the thermal surface concerned. The spreadsheet will then be sent to the competent authorities, who will return the certificate necessary for your building permit application.
The price of a thermal study is generally between 50 and 750 € TTC. The price of the study depends in particular on the area concerned by it and the services included in the package. Note that this document is systematically included in the price of the building permit when the file is made up of an architect.
When determining the cost of a building permit, it is necessary to take into account the local taxes induced by the issuance of such an authorization.
Thus, any construction, reconstruction, development, extension, or change of destination of a building is subject to the payment of the development tax, as soon as the area concerned is greater than 5 m² and has a ceiling height of at least 1.80 m.
The amount of the development tax is calculated as follows:
Taxable area x Lump sum value per m² x Rate in force in the local authority
If the rate varies according to local authorities, the standard value is defined by decree and updated each year. In 2020, the value per m² of the development tax amounted to € 860 / m² in Ile-de-France, and to € 759 / m² in the provinces.
Note that certain facilities or equipment are subject to a flat-rate development tax: € 200 / m² for a swimming pool, € 3,000 per wind turbine of more than 12 m, or € 10 / m² for photovoltaic panels fixed to the ground.
In addition, know that the new area created will have to be declared to the tax administration, which will result in the annual settlement of:
- property tax, by the owner of the building
- the housing tax (or its revision, if you are already affected by this tax), by the person who occupies the accommodation (the tenant, if the accommodation is rented).