Ask This Old House Season 22

The International Rose Test Garden; replacing damaged bathroom tiles; reviewing comments from viewers.

IAQ testing; restoring a Victorian firebox; transitioning landscapes from spring to summer; organizing a tool storage cabinet.

Ross Trethewey helps a homeowner install a smart thermostat after discovering he's missing a common wire; Mauro Henrique shares deck staining tips, what stain options are available, and the level of maintenance required for each type of stain; Mark McCullough helps a homeowner revive his bluestone patio by showing how to use the appropriate tools and materials to clean it.

Lee Gilliam helps a homeowner improve the soil conditions of her garden bed before installing new plantings; a New Hampshire painter and business owner shares her journey in the trade; Heath Eastman helps a homeowner mitigate bathroom moisture by installing a remote bath vent and timer switch but runs into some trouble when he finds old wiring in the wall.

Mauro Henrique shows a homeowner how to brighten up her basement apartment by painting with various paint concentrations; Richard Trethewey and Mark McCullough explain a variety of culprits and solutions for basements that are struggling with water issues; In Build It, Kevin O'Connor and Tom Silva show how to construct a bat house.

Jenn helps a couple rethink their front yard after two removed trees changed the shade pattern of the space; Richard talks about the mentors who helped him become a passionate teacher on This Old House; Richard gives Kevin a tour of the building he and his son, Evan Trethewey, have renovated to bring a new experience of mechanical equipment to contractors

Jenn Nawada and Nathan Gilbert travel to Tulsa to learn about the city's rain barrel and stormwater management initiatives and help a homeowner install one in her own garden; Mark McCullough helps a homeowner redirect pooling water on her patio with a weep hole drilled into the stone wall; the team goes through a few new additions to their tool bag that they've enjoyed having on hand lately.

Richard Trethewey shares his appreciation for modern plumbing, then helps a homeowner with an all-electric heating system retrofit a radiant floor system under their bathroom; Nathan Gilbert shares connection options and maintenance for cable railings; Jenn Nawada shares changes to the USDA Plant Hardiness Zone map and how to use the information to select the best plants for a landscape.

Lee Gilliam helps a homeowner figure out why grass doesn't grow in his backyard before installing a shade-tolerant species of sod; Ross Trethewey talks through converting houses' heating and cooling systems to heat pumps; Kevin O'Connor meets maker Sarah Nadarajah, the creator of Rocky Canyon Rustic, to learn about her content before building a replica high-end side table.

Nathan Gilbert helps a homeowner add shade to a pool area using a shade sail and unique anchor points; Ask This Old House spotlights the brothers of Jordan's Legacy Landscaping, a fourth-generation landscaping company in the Atlanta area; Mark McCullough helps a landlord make a cost-effective repair to her tenant's concrete walkway.

The Ask This Old House team head to California to explore a variety of ways that homeowners can protect their houses against wildfires. Jenn Nawada learns about local flora and helps firescape a front yard, Tom Silva learns how to fire harden a home's exterior, and Richard Trethewey learns a unique weeding technique that helps to mitigate the risk of fire spreading.

Lee Gilliam helps a homeowner clean up his backyard by removing a diseased tree and shows how to remove and maintain invasive plants; Mark McCullough discusses the function of chimney caps, options available, and how homeowners can know if they need to install one; Richard Trethewwey installs a toilet with a built-in bidet for a homeowner and shares the variety of options available.

Mauro Henrique discusses how he sees color, and shares some of his favorite colors to use for projects; Then, he updates a homeowner's office by painting over dated wood paneling with the perfect dark blue; Lee Gilliam discusses various shrub pruning tools; Nathan Gilbert heads to Portland, Oregon to help a homeowner build a sensory mud kitchen for her at-home daycare.

Heath Eastman shares his tips and tools homeowners can use to identify and label home circuit breakers; Tom Silva discusses his hobby of lathe turning, why he enjoys it, and shares some of his favorite pieces he's created. Then, in Build It, he shows how to turn a segmented bowl, which is comprised of multiple pieces of wood glued together and turned, creating a unique visual effect.

Richard Trethewey helps a homeowner troubleshoot why her upstairs shower runs out of hot water so quickly and helps her install a heat pump water heater; Kevin O'Connor returns to maker Jimmy DiResta's workshop in Upstate New York to get a lesson in leatherworking as they hand stitch a leather tote bag.

Nathan Gilbert shares his love of flea markets, what items he's found, and what he recommends looking for; Mauro Henrique teaches a homeowner how to paint over old garage graffiti and which primer is right for the job; Ross Trethewey shares how radon tests can detect harmful levels of radon in homes; Nathan helps a homeowner ready her nursery for a second baby by installing closet shelving.

Nathan Gilbert helps a homeowner create a backyard entrance by converting a window into a backdoor; The team discusses what they look for in houses for sale that could be considered deal breakers for homeowners not looking to undertake major repairs or renovations.

Heath Eastman shares what factors to consider when selecting a generator, such as fuel or electrical load, and the options that are available; Jenn Nawada shares how to build a worm farm, what foods to incorporate and exclude when feeding the worms, and the many benefits of worm composted soil; Mauro Henrique refreshes a homeowner's vintage front door with a fresh coat of paint.

Lee Gilliam shares the key tools and products to include in a winter weather kit to prepare for winter; Mark McCullough shares his favorite homeowner-friendly masonry tools and how to use them for entry level projects; Tom Silva and Kevin O'Connor upgrade the workspace by building a new mobile miter saw station, featuring two work benches and cabinets for extra storage.

Jenn Nawada teams up with a water conservation expert in Portland, Oregon to help two homeowners install a rain garden; Ross Trethewey shares how moisture meters can detect unseen water damage; Mark McCullough helps a homeowner increase the safety of their concrete steps by installing a wrought iron railing and showcases how railings are made at an iron fabrication facility.

Mauro Henrique shares the importance of prep work for any painting project, and why homeowners shouldn't skip it. Then, Mauro and Kevin O'Connor team up to refinish an antique outdoor bench with a whitewash stain; With a glass expert's help, Tom Silva learns how double pane glass is made while helping a homeowner repair a broken window.

Heath Eastman assists a homeowner who wants to hook up a generator to their home by installing a transfer switch to the circuit board; Environmental contractor, Ron Peik demystifies asbestos and shares options for mitigation; Mark McCullough fixes a faulty brick lintel repair on an 1833 home, discusses the difference between Flemish and American bond, and how to match existing mortar and joints.

Nathan Gilbert heads to Tulsa, Oklahoma to build a replacement utility cover. Ross Trethewey discusses low-level carbon monoxide exposure, symptoms, and differences in CO detectors and low-level monitors. Mark McCullough helps a homeowner clean out creosote build-up in their kitchen fireplace and explains the dangers of creosote build-up, options for removal, and the safety preparation involved.

Ask This Old House welcomes landscape contractor, Lee Gilliam to the cast and shines a spotlight on his 30 years of experience; Richard Trethewey helps a homeowner repair a leaking 3-valve shower while retaining the bathrooms original 1930's tile; Lee and Jenn Nawada work together to refresh a homeowner's eroding sloped yard; removing excess mulch, and installing boulders and ground cover plants.

Heath Eastman helps a homeowner install outdoor-grade remote-controlled patio string lights over their backyard patio; Mauro Henrique color matches a homeowners retro aqua kitchen cabinet and repaints it to match the rest of the vintage kitchen; Mauro takes a sample of the aqua-colored kitchen cabinet and heads to Home Depot to demonstrate the color matching process.

Nathan Gilbert shares his own experience as a Boy Scout and introduces his niece's Girl Scout troop and the project they need help with; Tom Silva and Kevin O'Connor create a two-layered hexagonal herb planter for the garden; Jenn Nawada and Nathan pick up materials to build a garden bed and then team up to help the Girl Scout troop rebuild and replant their community garden beds.