Ask This Old House - Season 15

In the premiere of the 15th season, Tom replaces sash balancers on an antique window. Roger and Kevin check out the benefits of a robotic lawnmower. And Richard talks about treating water with lead.

Kevin visits Chicago to explore the dangers of home fires and ways to stay safe. Scott shows off a portable generator that doesn't run on gas. The guys ask, "What is it?" And Richard finds a rusted sink strainer in the kitchen.

Tom and Kevin use store-bought stair treads to create a bookshelf in Build It. And landscape designer Jenn Nawada transforms the look of a home's foundation by using existing plants.

Roger helps plant a home orchard using apple and pear trees. Tom shows Kevin how to choose and use a circular saw. Richard installs a new tank water heater and discusses new regulations on them.

Tom repairs a broken board on a front porch. Richard analyzes a homeowner's green-stained shower. Scott brings more power to a bedroom and is able to conceal the wiring with crown molding.

Richard learns about a way to heat and cool a house using a new room-by-room ventilation system. The guys ask, "What is it?" And Tom explains the best ways to patch a small hole in the wall.

Ross Trethewey helps build a robotic wall that could be the key to tight spaces in urban living. Tom and Kevin use reclaimed pine heart wood to create a bench with a historic theme in Build It.

Richard travels to Seattle to help a couple choose and install laundry appliances. Tom shows Kevin new table saw technology. And Scott repairs a three-way switch.

Kevin install a home elevator. Jenn Nawada investigates how to grow microgreens. Tom explains the best way to match historic moldings. And Richard diagnoses a problem with well water.

Tom heads to Chicago to transform a one-car garage into a carpentry workshop. Scott installs a wireless light switch. Richard gives a history lesson on antique bath fixtures.

Roger rips up an old, dangerous walkway to replace it with bluestone. Scott explains the best wire nuts to use for each project. Kevin gets a lesson on making mead.

Jenn shares an environmentally safe way to keep walkways safe. Tom gives a tutorial on hand saws. Richard diagnoses a hot water radiator problem. The guys ask "What is it?" Scott installs LED lights.

Jenn learns about rooftop and small space gardens. Tom explains best practices to remove stains from plaster and dry wall. Scott powers a shed by running electricity underground from the house.

Kevin heads to LA to meet up with Nick Offerman. Ross Trethewey looks at a new device to track home energy usage. And Richard shows what happens when you use the wrong soap in the dishwasher.

Tom creates wainscoting out of base cap molding. NASA astronaut Mike Foreman visits to show off a few space tools. Richard helps a homeowner to get enough hot water for his children's bath time.

Tom and Kevin use scrap to create an end grain cutting board. Scott installs surface-mounted downlights. The guys ask, "What is it?" And Roger discusses the best ways to keep mice out of your house.

Scott helps a homeowner raise and lower a light with a motorized lift. Tom shows Kevin the best uses for jigsaw and how to choose blades. Roger visits Kentucky to help a homeowner repair his lawn.

Tom installs a door knob passage set on a closet. Richard gives a history lesson about plumbing and shows off new toilet technology. Jenn uses a historic design as inspiration to revive a backyard.

Richard revisits a homeowner to repair a water heater. Tom installs a storm door with a dog in mind. And home technology expert Ross Trethewey looks at voice-activated smart devices.

Richard describes the dangers of CO2. Tom and Kevin build a home message center. The guys ask "What Is It?" Scott replaces track lighting. Jenn walks through inspiration for a landscape design.

Richard helps a homeowner improve her drinking water with a whole house filter. Jenn creates a backyard sanctuary with a patio and fire pit. Tom explains the differences between soft and hard wood.

Scott heads to Alaska to hook up a portable generator powering an entire house. Tom repairs a poorly installed piece of wood floor nosing. Richard gives an inside look at dishwasher cycles.

Richard uses cameras to locate a drain problem. Scott warms up a chilly bathroom, installing an electric convection heater. Mauro demonstrates a masking primer that leaves clean lines on a window.

Tom and Kevin create a planter box in Build It. Ross Trethewey features a tablet attachment that makes 3D scans of home interiors in Future House. Scott explains the need for surge protection.

Jenn plants a rain garden to keep runoff and waste out of marshlands. Scott brightens up a bedroom with new overhead lighting. Tom gives tips on installing cabinets accurately and consistently.

Tom learns how to create a unique keepsake box from island materials in Build It. Richard looks at a new way to store solar energy. Roger helps a family grow an organic garden.