Ask This Old House - Season 7 Episode 22
Heating & Cooling System Controller; Re-Grout Tile Floor

Plumbing and heating expert Richard Trethewey helps a California homeowner install a new type of "zoning" control for her forced-air heating and cooling system. Then Richard, along with landscaping contractor Roger Cook, host Kevin OConnor and general contractor Tom Silva ask, "What is it?" Next, Tom helps a homeowner re-grout the tile floor in her master bathroom.