Fire gutted the Lotus hospitality suite at the Malaysian Grand Prix and caused smoke and soot damage to Kimi Raikkonen and Romain Grosjean's race gear, officials said on Saturday.
No one was hurt in the overnight blaze, believed to have been started by a faulty fridge, which forced the abandonment of the two-storey temporary suite being used for this weekend's grand prix at Sepang.
But equipment belonging to ex-world champion Raikkonen and Grosjean was being hurriedly cleaned for Saturday's qualifying session after being coated with soot. Raikkonen's spare helmet "perished in the blaze", a statement said.
The hiccup adds to a bumpy week so far for Lotus, whose main driver Raikkonen has been penalised five grid places for Sunday's race after fitting a new gearbox.
Raikkonen, the 2007 champion who spent the last two years in rallying, started 18th on the grid at last weekend's season-opener in Australia, although he fought through the field to finish the race seventh.
"The team asks for forgiveness for certain personnel who have entered the fire-damaged facility as they will be rather smoke-fragranced today," a Lotus statement said.