Parc fermé

What it means in practice

When a car enters parc fermé conditions (typically when it leaves the garage for the first qualifying session), the team loses the right to make most setup changes. Adjustments still permitted include^[1]:

• Front wing flap angle (within a defined range)
• Brake bias
• Tyre pressures within Pirelli's allowed range
• Some power unit settings used for fuel and energy management

Changes outside that allowed list require either:

• A penalty (pit lane start for the race)
• Or a documented force majeure event (component failure) approved by the stewards

Why the rule exists

Parc fermé was introduced to prevent the long-standing practice of teams running a "qualifying setup" (low fuel, fragile aero) on Saturday and then completely rebuilding the car for the race overnight. The rule forces a single setup decision that must work across both conditions^[2].

The strategic effect is significant. Teams cannot afford a pure one-lap qualifying configuration if it produces a car that cannot finish the race; they cannot afford a pure race configuration if it leaves them outside the top ten on the grid. The setup is always a compromise.

When teams break parc fermé deliberately

A small number of strategic situations make a parc fermé break worth the penalty:

• The car suffers crash damage in qualifying that requires a parts change beyond the allowed list.
• Weather forecast for the race shifts dramatically (e.g., from dry to wet) and the setup is materially wrong.
• A driver has qualified poorly and the race-from-pit-lane outcome is no worse than the predicted race finish from the grid position earned.

In those cases, teams will use the race overnight to make substantive changes, accept the pit lane start, and try to recover through strategy rather than pace.

Related

• Tyre degradation
• 107% rule