Watch Ask This Old House Season 9 Episode 18 Online

Up in the workshop, expert painter Mark O'Lalor shows host Kevin O'Connor a few tricks and techniques for painting an interior wall. Then Kevin, along with landscaping contractor Roger Cook, general contractor Tom Silva, and plumbing and heating expert Richard Trethewey ask, "What is it?" Afterward, Richard helps a homeowner install a new water heater with an electronic valve that prevents floods due to water leaks.