"I'm just a bit of a dick, sir," Christopher Ryan Clifton told a judge. "I just do dumb stuff."
He had just pleaded guilty to wilful damage after drunkenly throwing two rocks through his neighbour's window on October 25.
Clifton told police he was aiming at something on the roof.
"It was nothing personal, it was an error in judgment," he told Whanganui District Court on Tuesday.
Judge Dugald Matheson said Clifton had "a bit of a history of being an idiot".
He convicted Clifton and remanded him to December 9 for sentencing so a restorative justice conference could be held.