Measuring thresholds and furniture clearance

The two numbers and what the finder does with them

The robot vacuum finder compares your tallest threshold with the climb height each maker publishes. A robot passes when it climbs at least 2 mm (0.08 in) more than your threshold. It is tight when it climbs your threshold with less than that to spare, and it does not fit when its climb is lower than your threshold.

Furniture works the same way with a different margin. The finder adds 5 mm (0.2 in) to the published robot height, and the robot passes when that sum is at or below your gap. When a maker publishes no climb or no height, the model goes to needs a check. The finder never fills in the missing number.

How to measure a threshold

A threshold is any step the robot drives over: a door saddle, a strip where two floors meet, the lip of a balcony door or the edge of a thick rug.

1. Walk the route the robot will take and note every doorway and floor change on it, including rooms you may add later.
2. At each one, stand a ruler upright on the lower floor, against the highest point of the threshold. A steel ruler or a caliper reads to the millimeter; a tape measure will do for a first pass.
3. Read the height from the lower floor to the top. Where the two floors sit at different levels, the lower side gives the taller step, and the robot climbs it on the way back.
4. Measure rug edges the same way, from the bare floor to the top of the pile at the edge.
5. Enter the tallest figure you found. A single threshold the robot cannot cross cuts off every room behind it.

In inches, read to the nearest 1/16 in. The finder takes inches to two decimals: 1/2 in is 0.5 and 3/4 in is 0.75. The table at the end of this guide converts the common sizes.

Single steps, double steps and page claims

The climb height Botsize stores is the tallest single step the maker states. Several makers print a second, larger figure for two steps in a row, measured under their own conditions. The Dreame X60 Ultra is one example: 45 mm (1.77 in) for a single step and 88 mm for two steps together. The finder uses the single step, because a doorway is one step.

A few pages print one headline figure without saying what kind of step it means. For the Narwal Flow 2, the product page names 40 mm and the manual gives 30 mm (1.18 in) for a single step, so Botsize keeps the manual figure. For the Narwal Freo 20, the page names 40 mm (1.57 in) with a footnote that results vary, and the manual gives no single step figure, so the page figure stands. Each model page lists the sources behind its number.

31 of 42 vacuum records publish a climb height, from 15 mm (0.59 in) to 50 mm (1.97 in). 22 of them clear a 20 mm threshold with the margin and 15 clear 30 mm. The worked answers for 20 mm thresholds and 30 mm thresholds list them.

How to measure the gap under furniture

1. Choose the pieces the robot should clean under: sofas, beds, sideboards, a TV stand. Leave out the ones you are happy to skip.
2. Kneel and find the lowest point underneath. It may be a crossbar, a rail or the frame of a bed base rather than the front edge you see standing up.
3. Measure from the floor to that point. On a rug, measure from the top of the pile, since the robot drives on the pile.
4. Check both ends and the middle. A sagging base or an uneven floor can leave one spot lower than the rest.
5. Enter the lowest gap you found as the lowest furniture to clean under.

The robot height Botsize stores is the overall height, including any LiDAR turret at its lowest position. Some robots lower the turret into the body to pass under furniture, and for those the stored height is the lowered one.

37 of 42 records publish a robot height, from 79.5 mm (3.13 in) to 119 mm (4.69 in). 12 of them pass under a 95 mm gap. Of the 8 models under 85 mm, 7 either lower their turret or have none on top. The answer for a 90 mm gap under the furniture lists the ones that pass.

When the maker publishes no number

11 records publish no climb height and 5 publish no robot height. The finder lists those models under needs a check, with not published in the row. Check the manual or ask the maker before you count on one. The data page shows how complete each field is.

Inches and millimeters