In which case must you hire an architect in France?

23 October 2017

You have a project for the construction, renovation or expansion of your property in France. When are you required to hire an architect? What are the advantages and disadvantages ? Let’s do a check in.

Since March 1, 2017, you must contact an architect as soon as the threshold of 150 m² floor area is crossed. Using a professional is also a guarantee that the project will be adapted to your needs, your budget and the environment of the property.

Before 2013, the threshold was of 170m. The new measure equally applies on works of expansion if they drive the floor area or the footprint to exceed 150 m².

In which case do you have to call on an architect in France

Floor surface area or footprint …

The term “floor surface” means the closed and covered surfaces after deduction in particular of the thickness of the walls and surfaces of a height less than or equal to 1.80 m. As for the right of way on the ground, it is the projection of the shadow on the ground of the housing when the sun is vertical.

Warning ! If the project is envisaged by a legal entity such as a real estate civil society (SCI), for example, it must obligatorily, whatever the surface of the building, to approach an architect. Moreover, if you build in a classified site or if you renovate a historic building, the opinion of the architect of the buildings of France (ABF) is imperative and compulsory.

How to find a performant professional?

For any building larger than 150 m2, you must use a state-certified architect or a government-certified architect (DPLG: diploma issued before 2007), registered with the order of architects.

To choose a professional, apart from word-of-mouth, you can consult the site, created by the order. Depending on the project (new construction or renovation) and the location of it, the site offers you a list of professionals and architectural firms near you with, in support, visuals of their achievements.

It is equally possible to have some free advice with the council of architecture, urbanism and environment of your departement ( or the Maisons de l’architecture, in most regions (

What budget is needed for a consultation?

The fees of architects are free and depend mainly on the fixed price or the percentage of the cost of the works. Package remuneration is often used for a floor area of less than 150 m2 and for tight budgets. But tariffs per square meter can also be practiced for small spaces.

Remuneration as a percentage of the amount of work is the formula used in other cases. In general, it is the overall cost that serves as a basis, but a modulation of the rate per tranche is possible.


  • From 30.000 to 100.000 € HT :15 % of fees
  • From 100.000 to 150.000 € HT : 13 % of fees
  • From 150.000 to 250.000 € HT : 10% of fees
  • Beyond 250.000 € HT : 7% of fees.

Finally, the architect applies a fee to the shift for short missions, such as advice or expertise. In any case, the agreement you sign with him must mention his method of remuneration and fees.

It should be noted that the architect’s tariffs depend on his reputation, his region of practice, the financial cost of the operation, the extent and difficulty of the assignment you entrust to him.

In any case, it is difficult to know the final cost of a construction as long as the companies consulted have not yet provided their estimates.

It is therefore advisable to provide for a specific clause within the contract specifying that the remuneration of the architect initially foreseen will be reduced if the total cost of the work exceeds a “tolerance” margin (10%, for example, between the estimated price and the actual price).

Keep in mind, however, that the cost of an architect is partly offset by the savings it makes you realize, namely lower building rates through competition between several companies, saving energy due to the design of high-performance technical solutions, etc. Besides saving time!

Cabinet Roche & Cie, English speaking accountant in Lyon, France.
Specialist in Real-Estate and Non-resident taxation.

The Team Roche & Cie

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