A boulder the size of a car came crashing through a home in Vista Tuesday.The incident happened around 11 a.m. in the 1500 block of Brengle Way, according to authorities."I'm not good at guesstimating, but six tons or so," Vista Fire Capt. Jay Ackerman said of the boulder.Ackerman showed 10News pictures of the destruction his crew saw when they responded to a 911 call that a boulder had struck a house."We found that it not only struck the wall but it had gone all the way through and embedded itself into the floor," said Ackerman.The boulder created a gaping hole in the back wall of the house and smashed furniture inside. The homeowner, who was in the next room, told authorities he thought he heard thunder. However, a few seconds later the homeowner said it felt like the whole house had exploded.The boulder came from an outcropping of rocks that sat just above the property. Firefighters said they believe rain and gravity caused the mess."I think just over time, with the storm, with the wet ground, things giving away in front of it, it was just allowed to roll out," said Ackerman.A building inspector was called in and later determined the house was safe.