Flames tore through the attic where lightning hit Monday morning in the Copperfield area.
The Cy-Fair fire chief told ABC13's Courtney Fischer that the homeowner was sleeping when he heard some sort of "loud boom and explosion." His dog started barking and his alarm went off.
A neighbor saw smoke and flames coming from the roof and warned the homeowner.
The homeowner and his cat came out of the fire safely.
The National Weather Service reports more than 6,000 lightning strikes in the past hour.