Ask This Old House S24E20: Top-Down Shades for a Barking Dog, a Toilet Tank Autopsy, and a Steep Yard That Needed a Swale

Season 24, episode 20 of Ask This Old House stacks three house calls that share almost nothing: a window treatment, a plumbing history lecture delivered from inside a bathroom, and a front yard trying to leave for the street. Watch them back to back and a theme still surfaces. Every job is about where something goes. Daylight into a living room. A measured 1.6 gallons through a bowl. Stormwater down a slope, ideally not across the sidewalk.

Top-Down Cellular Shades for a Dog Who Takes the Perimeter Seriously

Nathan Gilbert meets homeowner Lianne and Cece, a small dog with a large territorial streak. The existing shades lower from the top only, which is exactly the wrong direction for a dog whose whole hobby is watching the street. Nathan's fix is a cellular shade that runs both ways: top down to block the sightline at window height, bottom up when you want the light and the view back.

Before any of that matters, there's a mounting decision. Inside mount sits the shade between the window casing; outside mount covers the casing and then some. Inside mount needs a minimum of 3/4 inch of depth to hold the brackets, and Lianne's windows measure 1-1/8 inch. Decision made.

Then the part that decides whether the shade fits or comes back. Nathan measures the width in three places, bottom, middle, and top, and orders to the smallest number. Here that's 33-1/8 inch at the bottom. Height gets the same treatment and comes back uniform at 51-1/2 inch. He sends those numbers to the factory, which takes roughly 1/8 inch off the width so the shade has room to snap into its brackets. Order a shade by the largest measurement and you're the person on the phone explaining why it doesn't fit.

Installation itself is almost anticlimactic. The brackets land 3 inches in from each side, inside the 2-to-4-inch range Nathan cites. He pre-drills with an 1/8-inch bit sized to the screw shank so the threads do the biting, not the shank, and each bracket needs only one screw in this case. Lianne drills and drives one side herself with Nathan coaching her to keep weight behind the drill. The shade hooks onto the brackets, a handle snaps onto the rail, and the whole thing lifts into the top-down position with two hands.

What the edit compresses is everything that happens before the van shows up: measuring each window in the house, placing the order, waiting, picking it up, then repeating the bracket layout and install window after window. The on-screen version runs a few minutes. The real version is an afternoon, and the measuring is the whole job. The shade installation is the easy part, roughly the same rhythm Nathan used hanging a porch swing with a helper in S24E16, minus the structural math and with a smaller apprentice.

Richard Trethewey Opens a Toilet Tank and Finds 150 Years of Engineering

Kevin finds Richard in what Richard insists on calling his lavatory, standing next to a high-tank toilet from roughly 1880 or 1890. The tank is wood lined with copper and sat up on the wall, using nothing but the weight of water to move things along. It carried four components: a tank lever to start the flush, a flush valve to let water leave, a fill valve to put water back, and a copper tank ball that floated up to shut the incoming water off. The overflow, Richard notes, wasn't an overflow you wanted. If the water didn't stop, it went through the floor. Which is why these toilets often lived in the basement.

Those four parts exist in every toilet tank now, just reshaped. The middle era brings bronze and brass flush valves with stem wires and lift wires, all proprietary, all fussy, and a tank ball that had to drop into a perfect seal and mostly didn't. The flapper fixed that by hanging on two shanks built into the overflow tube so it landed in the same spot every time. The fill valve went from a plastic ball on a bendable rod, which was its own kind of adjustment, to a modern unit with the float built into the shank and a screwdriver slot for setting the water level.

Richard traces the water, which is the useful part for anyone standing over an open tank. The flush valve dumps water down into the rim, where small holes under the rim scour the sides of the bowl, and out through a siphon jet at the bottom to start the siphon that actually pulls the bowl clean. The refill tube then sends a little water down the overflow after the fact to bring the bowl back to the right level. That's why the bowl refills even though nobody touched it.

The numbers make the precision make sense. Toilets went from 4 to 5 gallons per flush to 3.5 by mandate and now to 1.6. There's no margin left for a flapper that hangs open or a float set too high, so Richard names the two adjustments he expects a homeowner to handle: the tank lever linkage travel, so the flapper gets the right amount of lift, and the float height, set with a Phillips screwdriver so the water sits about 3/4 inch below the top of the overflow tube. Start there before you start replacing parts.

Kevin spends the segment asking the questions a curious homeowner would ask and gets called a prospective toilet docent for his trouble. If you've been keeping a Kevin's Helper Scorecard through this season, that's a strong episode for questions and no tool time at all. Richard did the flushing.

The plumbing-diagnosis thread also runs through S24E17, where Richard sorted grease and hair clogs from the drain chemicals people pour at them. Same method here: understand the mechanism before you buy a fix for it.

Jenn Nawada Softens a Steep Front Slope and Gives the Water Somewhere to Go

Shannon and her husband just moved into a house with a front yard that runs between 10 and 12 feet down to the sidewalk. Too steep to mow, so it's been kept in check with a weed whacker. An old photo shows the previous owners had a mulched bed with bushes; somewhere along the way that disappeared, and the slope has been shedding grass seed ever since.

Jenn Nawada's plan is regrading first, planting second. Before anything moves, she calls 811, and it's a good thing, because there's a gas line in the work zone. Frank arrives with a mini excavator fitted with a clean-out bucket and a smooth-edge bucket for reshaping, and the gas line gets hand-dug around regardless. The machine works top down, shaving the hump and cutting a shelf into the slope with a swale to divert water before it heads for the sidewalk. Jenn and Shannon finish the sidewalk edge with flat-head shovels. Then the plants go in.

The planting list is doing two jobs at once, erosion control and curb appeal. The middle mass is Panicum virgatum, switchgrass, chosen for roots that spread and knit together underground and top growth that fills in as one stand, about 4 feet tall with movement in the wind. Little limelight hydrangeas, six of them split between both ends, go in at roughly 4 feet by 4 feet and bloom from July into the end of the season. Three endless summer hydrangeas sit on the shelf Frank carved, the blue ones, where the point is slowing water down. A Japanese threadleaf maple at the top spreads 8 to 12 feet. Full-size limelights at the far end reach 8 to 10 feet and screen the busy road.

Jenn's planting technique is worth copying closely. She digs the holes small at first because plants roll downhill on a slope. Compost and a handful of starter fertilizer go in and get mixed with the existing soil. Root balls get broken up and teased apart, because roots circling in a pot will keep circling in the ground. Plants go in slightly high, since mulch will bury the crown a bit anyway. Leaf mulch goes on 2 to 3 inches deep, then gets pulled back off the base of each plant by hand.

Maintenance Timing, Which Is Where Nice Yards Fall Apart

Grasses and limelight hydrangeas get pruned at the same time, February or March, before new growth starts. Limelights bloom on new wood, which is why cutting them back then is safe. Grasses get cut to 2 to 3 inches high. Endless summer hydrangeas bloom on both new and old wood, so they get deadheaded at the end of the season instead. The maple gets left alone. Watering continues through the end of the season, with drip irrigation planned for the shrubs and tree and spray for the grasses, and an inch of leaf mulch as top dressing next year.

Slope work keeps showing up this season. The granite steps in S24E17 were about getting a person up a hill safely, and the lawn regrade in S24E8 was about a lumpy yard with moss and drainage trouble. This one is water first, footing second.

What the edit skips: utility locating takes days, not minutes. Hand-digging around a gas line is slow, deliberate work. And new plantings need establishment watering for a full season, which the maintenance list compresses into a sentence.

DIY Confidence Scale

Shades: 4/5. Measuring in three spots and ordering to the smallest width is the entire skill. Bracket layout, pre-drilling, and hanging are well within reach of anyone who owns a drill and a pencil.

Toilet tank: 3/5. The two adjustments Richard names, linkage travel and float height, are genuinely homeowner-level. Diagnosing which part is failing is the harder half, and a cracked flapper or a scaled valve seat isn't fixed by turning a screw. Watch the whole segment before opening the tank lid.

Steep slope regrade: 1/5 for the excavation, 3/5 for the planting. A mini excavator, a gas line in the work zone, and a slope that sheds water toward a public sidewalk are three good reasons to hire this half out. Planting the bed once it's shaped is a weekend job with a shovel and a lot of watering.

Additional Resources

• Watch the full episode on PBS
• Official This Old House episode page

Two numbers from this episode are worth writing down before you touch anything: the smallest of the three width measurements, and the water level sitting about 3/4 inch under the top of the overflow tube. Both jobs go sideways when someone rounds up.