First showing in 2002, Ask This Old House is a spin-off of the popular home improvement series. In this show, the team from "This Old House" goes from door-to-door across America to help people with home improvement tips. The same guys from This Old House appear, master carpenter Tom Silva, plumber Richard Trethewey, and landscaper Roger Cook. The series was hosted by Steve Thomas in its first year but was later taken over by Kevin O'Conner along with sister show This Old House.

Each episode typically features two or three home visits along with a series of regular segments. In "What is it?" the guys have to guess the proper use of a strange tool or object before finding out it's actual use. In "Tom's Tips", Tom Silva gives the viewer various tips on using tools, and in "Viewer Mail", different viewers give their own advice or send in questions of their own.

This Old House and Ask This Old House play on most PBS channels together as "The This Old House Hour".