Workers razed the house in East Haven after their company obtained permits and the site was tested for environmental hazards, Mayor Joseph Maturo Jr. said.
The house was empty when a 10-seat plane crashed Aug. 9 while approaching Tweed New Haven Airport. The cause remains under investigation.
A 13-year-old girl, Sade Brantley, and her 1-year-old sister, Madisyn Mitchell, died in the house next door. Two people on the plane also died: the pilot - former Microsoft executive Bill Henningsgaard of Medina, Wash. - and his 17-year-old son, Maxwell, who were visiting colleges on the East Coast. The girls' mother survived.
The cause of the crash remains under investigation. The National Transportation Safety Board issued a preliminary report Tuesday saying a witness saw the aircraft traveling upside-down as it sped nose-first toward the ground.
The house where the girls lived also will be torn down, but demolition is being held up by environmental concerns over jet fuel, Maturo said.
Maturo said in a statement that if the insurance company for the home where the girls died does not act quickly to have it razed, town officials will take action.
"As painful as it is for the homeowners to watch their homes come down, the raising of these homes is a difficult but important step in the healing process for these families and for the neighborhood," the mayor said.