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Robot vacuum docks, explained
Much of the price difference between robot vacuums is now in the dock: a base station that empties, washes, dries and refills so you touch the robot less. Here's what each dock feature does, and what it adds to your running costs.
The short answer
- Self-emptying is the feature that saves the most hands-on time. Most bases use disposable bags, which are a recurring cost.
- Mop washing and drying matter only if you mop. Hot water helps with greasy floors; drying matters for smell.
- Auto refill and drain connects the dock to your plumbing. It's often a separate model or regional option, and it needs installation.
- Mop lifting decides whether wet pads drag across your rugs. Check the height in millimeters, not the marketing name.
Self-emptying
After each run the dock sucks the robot's small onboard bin into a larger container in the base. You empty the base every few weeks instead of the robot every day.
- How long between emptying: Narwal says most bagged bases hold dust for 30 to 60 days. Roborock rates its Qrevo Curv at up to 7 weeks, depending on use. These are maker estimates; homes with pets or carpet fill faster.
- Bagged vs bagless: most bases use disposable bags, which keep dust contained when you empty them. Bagless bases, such as Shark's, avoid buying bags but you tip the dust out yourself, which matters if anyone in the house is sensitive to dust.
Mop washing, hot water and drying
Mop docks rinse the robot's pads in a tray between rooms or after a run, using a clean-water tank and collecting the dirty water in a second tank you empty by hand.
- Hot water: premium docks heat the wash water. Roborock lists 75°C (167°F) for the Qrevo Curv and settings from 50 to 80°C for the Saros 10; Dreame says up to 80°C for the X50 Ultra. Hot water helps lift kitchen grease. Some budget docks wash in room-temperature water.
- Drying: after washing, warm air dries the pads so they don't sit damp. Roborock lists 45°C air for the Qrevo Curv and up to 60°C for the Saros 10. Damp pads are a common cause of a smelly dock.
- Detergent: some docks dose floor cleaner automatically. Roborock's Qrevo Curv has a 600 ml detergent tank. Check your manual for which cleaners the maker allows before pouring in your own.
Auto refill and drain
A plumbed dock connects to a water supply and a drain, so you never carry tanks. Roborock sells the Saros 10 in a separate refill-and-drainage version and says the Qrevo Curv's version is only available in certain regions. Dreame's installation page for Singapore asks owners to finish any plumbing, wiring and carpentry before its technician visits. Treat it as a small plumbing job: you need a water line and drain near where the dock will sit.
Mop lifting and rugs
When the robot reaches a rug, it can lift its pads so they don't drag wet across it. Heights vary a lot: Roborock lists 10 mm for the Qrevo Curv, and our floor-cleaning guide lists the lift height for every mopping model we cover, from 10.5 mm to 17 mm. If you have thick rugs, a higher lift matters more than almost anything else on the box. Some robots detach their pads in the dock before vacuuming carpet instead.
Docks on the robots we cover
| Robot | What its dock does | Mop lift |
|---|---|---|
| Roborock Q7 M5+ | Empties into a 2.7 L bag (up to 7 weeks); no mop washing or drying | None (single pad) |
| MOVA P10 Pro Ultra | Empties into a 3.2 L bag (up to 75 days); hot-washes and hot-air dries the mops | 10.5 mm |
| Dreame L40 Ultra Gen 2 | Empties into a 3.2 L bag (up to 100 days); washes mops in room-temperature water; hot-air dries; refills water | 10.5 mm |
| Narwal Freo Z10 Turbo | Empties into a 2.5 L bag (up to 120 days); hot-washes and dries mops; refills water | 12 mm |
| Roborock Qrevo CurvX | Empties; washes mops at up to 80°C; dries with warm air; refills water | Up to 17 mm |
| MOVA P70 Pro Ultra | Empties; washes mops at up to 100°C; dries at 70°C; refills solution | 10.5 mm |
| Dreame X50 Ultra | Empties into a 3.2 L bag; washes mops in 80°C water; hot-air dries | 10.5 mm |
From the figures recorded in our floor-cleaning guide, with prices and 3-year costs there. Bag-life figures are maker estimates; the Narwal dock details come from an independent review, as noted on its card.
What each feature adds to running costs
| Feature | What you keep buying | Example official prices (Oct 12, 2026) |
|---|---|---|
| Self-empty (bagged) | Dust bags | Roborock dust bags, 6-pack: $25.59 |
| Self-empty (any) | Filters, brushes | Roborock washable filter, 2-pack: $32.99; main brush: $22.99. iRobot j/i refill kit (bags, filters, brushes): $86.98 |
| Mop washing | Pads, floor cleaner | Roborock floor cleaning solution, 200 ml: $14.99 on sale ($18.99 regular) |
| Hot water and drying | Electricity | Not published by makers |
Prices from each maker's own US store on October 12, 2026; they change often. Our upkeep table turns these into a yearly estimate for each robot we cover.
Which dock do you actually need?
- Mostly carpet, no mopping: a self-emptying base is enough. A mop dock adds cost and upkeep you won't use.
- Hard floors, daily mopping: mop washing plus hot-air drying. Hot water if your kitchen floor gets greasy.
- Mixed floors with rugs: a high mop lift, or pads that detach in the dock.
- You never want to carry water: a plumbed refill-and-drain version, if your dock spot has a water line and drain.
The System Builder matches these needs to a complete system, and the worth-it calculator weighs the 3-year cost against your time.
Related: how robot vacuums navigate · robot batteries.
Sources
- Narwal: self-emptying robot vacuums (June 2024)
- Roborock Qrevo Curv product page
- Roborock Saros 10 product page
- Dreame X50 Ultra product page
- Dreame water hookup installation page (Singapore)
- Shark AI Ultra with bagless self-empty base
- Roborock US accessories store
- iRobot j/i series refill kit
All sources read October 12, 2026. Capacities and temperatures are the makers' own figures.
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