Ask This Old House (2002)

S6E16 Skylight; 3-Way Light Switch

General contractor Tom Silva assists a homeowner in replacing a skylight that's been leaking water into the kitchen below. Following this, Tom, along with host Kevin O'Connor, plumbing and heating specialist Richard Trethewey, and landscape contractor Roger Cook, delve into the question, "What is it?" Later, electrician Peg Preble teaches Kevin how to diagnose and fix a malfunctioning 3-way light switch.