Our 5th season kicks off with general contractor Tom Silva helping a homeowner repair an interior door that won't latch shut. Then Tom, along with landscaping contractor Roger Cook, plumbing and heating expert Richard Trethewey and host Kevin O'Connor ask, "What is it?" Then, Roger heads for "fabulous" Las Vegas, Nevada, where he helps a pair of homeowners select and plant a privacy screen using bamboo plants.

Plumbing and heating expert Richard Trethewey helps a homeowner replace a clogged aerator on his bathroom faucet. Then, up in the loft, landscaping contractor Roger Cook is joined by plant expert Carrie Kelly to learn about caring for houseplants. Then, general contractor Tom Silva helps a homeowner quiet a squeaky subfloor hidden underneath wall-to-wall carpeting using special "breakaway" screws.

Plumbing and heating expert Richard Trethewey helps a homeowner begin to remodel his bathroom by installing a new acrylic shower base. Back in the loft, Tom demonstrates the proper way to install backerboard and tile around a new shower base. Then, landscaping contractor Roger Cook helps a homeowner save water by installing a rain barrel to catch rainwater from the roof.

General contractor Tom Silva heads to Las Vegas to help a young homeowner organize her garage by installing new cabinets designed especially for garages. Then, in the "What is it?" segment, host Kevin O'Connor and landscaper Roger Cook test a new type of vacuum-assisted post hole digger. Afterward, electrician John Barros visits a homeowner who needs help installing a new ceiling fan. Then, up in the loft, John shows Kevin a few other ways of installing fan-rated electrical boxes.

Landscaping contractor Roger Cook and host Kevin O'Connor plant flower bulbs outside the barn. Then, up in the loft, general contractor Tom Silva shows Kevin how to makes straight rip cuts with a circular saw using a customized jig. Then Tom, Kevin, Roger and plumbing and heating expert Richard Trethewey ask, "What is it?" Afterward, Richard helps a homeowner eliminate the water hammer noise from his pipes by installing shock suppressors.

General contractor Tom Silva helps a homeowner with a large carpentry project: rebuilding a small exterior deck. They start by removing the existing deck, which has rotted and become unstable. Together, they build a new deck, including stairs and handrails, using pressure-treated lumber and composite deck boards.

Host Kevin O'Connor and energy efficiency expert Bruce Torrey conduct an energy audit of a house. Using an infra-red camera, they locate areas where weather-stripping and insulation can be improved. Then Kevin, along with plumbing and heating expert Richard Trethewey, landscaping contractor Roger Cook, and general contractor Tom Silva ask, "What is it?" Afterward, Richard demonstrates how to remove an old toilet seat that has corroded bolts.

Up in the loft, stone countertop expert Jason Keefe shows host Kevin O'Connor how to maintain stone countertops and prevent stains. Then Kevin, along with landscaping contractor Roger Cook, plumbing and heating expert Richard Trethewey, and general contractor Tom Silva ask, "What is it?" Afterward, Roger and fence contractor Mike McLaughlin help a homeowner install a chain link fence.

Host Kevin O'Connor and child safety expert Jeff Baril visit a homeowner to "childproof" her home. Then Kevin, along with general contractor Tom Silva, landscaping contractor Roger Cook, and plumbing and heating expert Richard Trethewey ask, "What is it?" Afterward, Richard helps a homeowner install a back-up sump pump that is powered by municipal water pressure instead of electricity.

Tile contractor Joe Ferrante helps a homeowner install a brand new kitchen backsplash using glass tile. Then, landscaping contractor Roger Cook helps a homeowner replace a damaged section of lawn using sod.

General contractor Tom Silva shows host Kevin O'Connor how to replace damaged cedar clapboards on the exterior of a house. Then Kevin and Tom, along with landscaping contractor Roger Cook and plumbing and heating expert Richard Trethewey ask, "What is it?" Then, Roger and chainsaw expert Tim Ard show a homeowner how to fell trees safely using a chainsaw.

Plumbing and heating expert Richard Trethewey heads to San Francisco to help a homeowner repair an old shower mixing valve. Then Richard, along with host Kevin O'Connor, landscaping contractor Roger Cook, and general contractor Tom Silva ask, "What is it?" Then, up in the loft, Kevin and Tom are joined by battery expert Tim Pugh to discuss battery technology in cordless tools and proper recycling of batteries.

Landscaping contractor Roger Cook takes a homeowner shopping for mulch and shows her how to re-mulch and edge her garden beds. Then, general contractor Tom Silva shows a homeowner how to replace broken sash balancers in his double-hung windows.

Landscaping contractor Roger Cook and arborist Matt Foti help a homeowner properly prune his overgrown willow tree. Then, plumbing and heating expert Richard Trethewey heads to Denver to fix a hot water heating system that doesn't provide enough heat to a newly-built addition.

Up in the loft, plumbing and heating expert Richard Trethewey shows host Kevin O'Connor different methods for clearing clogged drains. Then Richard and Kevin, along with landscaping contractor Roger Cook and general contractor Tom Silva ask, "What is it?" Afterward, Tom helps a homeowner install new kitchen cabinets.

Kevin O'Connor helps a homeowner select wall-to-wall carpet and install it properly with the assistance of a professional installer. Back in the Ask This Old House loft, Kevin, Tom Silva, Richard Trethewey, and Roger Cook examine an unfamiliar object and try to guess how it is used. Then Tom teaches Kevin a few important lessons for using a tablesaw safely. He demonstrates a new type of emergency brake that helps to prevent tablesaw injuries.

Tom travels to Sacramento to help homeowners repair a damaged section in the vinyl flooring in their kitchen. In the Ask This Old House loft, Tom, Richard, Roger and Kevin examine an unfamiliar object and try to guess how it is used. Then Roger goes to Las Vegas to help a homeowner repair his leaking in-ground sprinkler system.

Richard Trethewey helps a homeowner refinish her cast iron radiators. They remove the radiators and take them to a restoration specialist, who sandblasts the peeling paint and applies a new finish and makes them look new. Afterward, Kevin O'Connor travels to St. Louis to help a homeowner install a standby generator who lives an area with frequent power outages that last for several days.

Landscape contractor Roger Cook shows a homeowner how the brick stairs in front of his house have created a blistering "micro-climate," causing damage to an adjacent shrub. Together, they remove the ailing shrub and replace it with a heat-tolerant yew. Then Roger, along with host Kevin O'Connor, general contractor Tom Silva, and plumbing and heating expert Richard Trethewey ask, "What is it?" Afterward, Tom improves the ventilation in an attic by installing a solar-powered roof fan

General contractor Tom Silva removes the cracked and warped boards on an old deck and installs new composite decking using hidden fasteners. Afterward, plumbing and heating expert Richard Trethewey quiets down a noisy steam heating system

Richard assists a homeowner in replacing a corroded shut-off valve with a new one without using soldering. In the Ask This Old House loft, Tom, Richard, Roger and Kevin examine an unfamiliar object and try to guess how it is used. Then Roger helps a homeowner with her rose bushes so they will climb a two-rail fence.

Richard Trethewey assists a homeowner install a new bathroom radiator that will double as a towel warmer. In the Ask This Old House loft, Tom Silva shows Kevin O’Connor how to shape wood by using hand planes. Roger Cook helps a homeowner remove crabgrass from his lawn and prevent it from returning.

Roger Cook helps a homeowner replace a mailbox that had been damaged by snowplows. Tom Silva travels to St. Louis to help a a young couple repoint the failing mortar on the brick foundation of their home.

Roger shows two young homeowners the proper methods for mowing and edging their front lawn. In the Ask This Old House loft, Tom, Richard, Roger and Kevin examine an unfamiliar object and try to guess how it is used. Richard shows Kevin how to repair and maintain electric water heaters. Tom helps a homeowner repair a broken stair tread using a new type of wooden dowel.

In the Ask This Old House loft, Tom Silva shows host Kevin O'Connor how to build a simple workbench. Roger, Kevin O'Connor, Richard Trethewey and Tom Silva examine an unfamiliar object and try to guess how it is used. Roger then gives Kevin tips on how to tune-up a gas-powered lawn mower. Then Richard silences a whistling forced-air heating system by installing a bypass duct.