Parc fermé
Parc fermé (French for "closed park") is the set of rules that stops teams changing their cars between qualifying and the race. Once a car goes out in qualifying, its set-up is frozen. Teams can carry out routine jobs, but they can't swap parts or change how the car is set up. A team that breaks parc fermé has to start its driver from the pit lane.
The phrase also refers to the fenced-off area where cars are taken after qualifying and the race for checks.
When it starts and ends
On a normal weekend, each car goes into parc fermé the moment it first leaves the pit lane in qualifying, and stays there until the start of the race. If a car doesn't go out in qualifying at all, it's treated as being in parc fermé from the end of Q1.
Before that first run, teams have to give the FIA a sheet recording the car's suspension set-up, so there's a record to check against.
On a sprint weekend there are two separate periods:
- From the first run in sprint qualifying until the start of the sprint.
- From the first run in Grand Prix qualifying until the start of the Grand Prix.
Between the start of the sprint and Grand Prix qualifying, teams can change the set-up again. This window was added in 2024. Before then, a sprint weekend car was locked from Friday onwards, giving teams just one hour of practice to get it right.
What teams can and can't do
The general rule is that no part can be replaced or modified, and no set-up or configuration changes are allowed. The FIA publishes a list of exceptions, which covers routine work such as:
- adding fuel and changing tyres
- bleeding the brakes and checking the brake pads
- adjusting the angle of the front wing flaps
- cleaning the car and repairing small bits of damaged bodywork by patching them up
- changes for the driver's comfort, like moving the pedals or mirrors
Anything else needs permission from the FIA technical delegate. If a part is damaged, it can usually be replaced with an identical one. The team has to show it really is the same design and close in weight and function to the original, and the damaged part is handed to the FIA.
In 2026 teams can also ask, a limited number of times per season, to replace a damaged wing, floor or other bodywork with a different version, as long as that version has been raced before.
When the weather changes
If the forecast for the race is very different from qualifying conditions, the FIA can announce a "change in climatic conditions". Teams are then allowed to adjust cooling, such as opening up bodywork around the engine or changing the driver's cooling scoop. They still can't touch the suspension or aerodynamic set-up.
How it's policed
An FIA scrutineer is assigned to each car to watch what the mechanics do. Each team also has to fit a camera above each car in the garage, looking down on the whole car, which has to stay switched on through the weekend.
Overnight, the cars are covered and sealed. Any parts swapped with the FIA's approval are published before the race so everyone can see what changed.
Why it matters for strategy
Parc fermé forces teams to make a compromise. A car set up purely for one fast lap in qualifying might be poor over a long race, so most teams choose something in between.
Weather makes it harder. A team expecting rain on Sunday might add more downforce, which costs them on a dry Saturday. If they guess wrong, they're stuck with it.
That's why teams sometimes choose to break parc fermé on purpose. A driver who qualified at the back can switch to a better race set-up and start from the pit lane, giving up very little.
After the session
At the end of qualifying and the race, cars go to the parc fermé area at the circuit. Only a few team members per car are allowed in, to fit cooling fans and help with checks. The FIA picks cars for technical inspections, and the drivers are weighed with their helmets and gear on. Results only become final once these checks are done, and failing one can lead to disqualification.