Robot vacuums that can climb your door sills

Best overallMova Z60 Ultra Roller Complete

Think about the worst sill in your house, the sliding-door track out to the deck or the lip into the sunroom, because that’s the one a robot has to beat. The Z60 climbs a single step of 4.8 cm. Nothing else in our list goes that high. It costs between $1,000 and $1,800, which is one price band below our dearest robots.

Suction is 28,000 Pa, with two anti-tangle brushes underneath and a side brush that extends outward and lifts 10 mm. The mop is a 25.6 cm roller that slides out a further 4.1 cm along walls. On carpet the roller lifts 14 mm and a cover comes down over it, so a wet mop isn’t dragged across the rug in the room it has just climbed into. A front camera helps it steer around clutter.

The dock empties the bin into a 3.2-litre bag, washes the roller in water heated up to 80°C, dries it with hot air, refills the robot from a 4-litre tank and adds the detergent. The robot’s own bin is 210 ml, the second-smallest in our list, so it leans on that dock to keep going.

With its laser turret lowered the robot is 9.6 cm tall, so check that against your couch. The battery is 6,400 mAh, as big as any in our list, and a full charge takes about 4.5 hours.

The catch is the dock. It measures 46 by 39 by 55 cm, and it has to live on the side of the sill where the robot does most of its work, so pick the spot and measure it before you order.

If your sills stop at 4 cm and you don’t want a mop, the Dyson climbs them from a band lower. And if they’re 2.2 cm or under, you don’t need a climber at all, so buy the Tapo and stay in our under-$500 band.

Best vacuum onlyDyson R1 Nurovi Dry

Some houses have no use for a mop. If yours is mostly carpet, a mopping robot is carrying a water tank and a roller it will hardly use, and you’re paying for a dock that washes them. The R1 Nurovi Dry leaves all that out and still climbs a single step of 4 cm. Among the robots in our two bands under $1,000, no other gives a figure above 2.2 cm.

Suction is 21,000 Pa. An ultrasonic sensor tells carpet from hard floor, and in Auto mode a second sensor counts the dust coming in and raises suction where there’s more of it. The brush bar is silicone with a chevron pattern, and the side sweeper reaches out 27 mm into edges and corners on bristles meant to shed hair. It spots obstacles with line lasers.

The dock empties the robot and charges it, and it’s bagless, so there are no bags to buy. The robot is 9.6 cm tall, the same as the Mova with its turret down, and it weighs 3.4 kg. You set no-go zones and do-not-disturb times in the MyDyson app, which is also where you edit the map.

The catch is how long it runs. The R1 goes for 70 minutes and a full charge takes 6.5 hours, so in a large house one clean could be spread across the day.

So we’d pick it for a carpeted home of modest size with sills up to 4 cm. If you have tiles or timber you’d like mopped, or a sill over 4 cm, the Mova does both jobs from one band up. And a 2 cm sill doesn’t need this much robot, because the Tapo crosses it for under $500.

Best budgetTapo RV20 Max Plus

Before you pay for a climbing robot, go and measure, because the sill that looks like a wall from the couch may only be 2 cm high. The RV20 Max Plus climbs 2.2 cm. That’s a hair more than the 2 cm that most robots giving a figure manage, and no robot in our under-$500 band states a higher one.

It’s also 8.3 cm tall, the lowest of our three picks by more than a centimetre, so it’s the one to send under a low couch.

The dock empties the 300 ml bin into a 3-litre bag and measures 23 by 16 by 33 cm. The robot runs for up to 180 minutes, and its quiet mode is 52 dB. It stores up to four maps, which is handy in a split-level house where the real stairs mean carrying it between floors. There’s a flat mop pad with a 300 ml tank and three water levels for a light wipe, and the robot keeps off carpet while it’s mopping.

The catch is the vacuum. Suction is 5,300 Pa, against 21,000 on the Dyson and 28,000 on the Mova, so it suits hard floors and flat rugs far better than thick carpet, though it does raise suction when it’s on carpet. It relies on its mapping laser alone to spot obstacles, so pick up cables and socks before it runs. The battery is 2,600 mAh, and a full charge takes four hours.

If one sill in your house is over 2.2 cm, this robot will treat it as a wall and you’d be carrying it across. In that case the Dyson is the next step up for a carpeted house, and the Mova is the one that climbs highest and mops.