"We had a really bad tropical storm with winds up to 90 miles per hour. A big lightning storm came around 4 a.m. and hit the house," Branson said in a statement Monday.
The Oscar-winning actress, 35, was staying in an eight-bedroom house on Necker Island with 10-year-old daughter Mia, 7-year-old son Joe and boyfriend Louis Dowler. Branson's mother Eve, 90, and daughter Holly, 29, were also among the guests. Everyone safely escaped.
"We want to rebuild the house as soon as we can," Branson added. "There's a lot of damage and we won't be able to stick it back together again right away ... It was a beautiful house."
Branson, the billionaire boss of the Virgin Group conglomerate that includes airlines, was staying in a nearby house with his wife and son.