(Recasts with house burning down)
By Jon Herskovitz
AUSTIN, Texas June 13 (Reuters) - Demolition crews on Friday burned down a luxury house that had been left dangling 75 feet (23 meters) above a lake when a decaying cliff gave out underneath the abandoned structure.
After a planned burn where crews set fuel-soaked bales of hay at strategic points throughout the house, most of the structure was reduced to ashes or plunged to the lake's coast within an hour of the fire being lit.
TV news helicopters circled over the house, that once had an estimated value of $800,000, for live broadcasts of the blaze, which took place on Lake Whitney, about 75 miles (120 km) southwest of Dallas.
The owner of the teetering mansion decided burning it down was the best way to safely demolish a structure left dangling when a large section of ground collapsed under its foundation on Tuesday, officials said.
The land started to give way around the house in February, and since then about 50 yards (metres) of land that separated it from the water's edge has eroded, said Mark Wilson, the chief deputy for the Hill County Sheriff's Department.
"There is quite a bit of land that got pulled into the lake," he said.
Owner Rob Webb, who spent his retirement savings on the house, has abandoned the property. He told Dallas television station WFAA he had trouble recognizing the structure from news reports.
"You're like, 'Good grief, that is my home,'" Webb told WFAA.
The house was built in 2007 and inspected before purchase. Webb is likely to be billed for the cost of its destruction and removal, local media said. (Reporting by Jon Herskovitz; Additional reporting by Jana J. Pruet in Dallas; Editing by Eric Beech and Sandra Maler)