Read the guide: Why does my washing machine shake?
How to measure floor vibration from your washer
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Step 1: Start a spin cycle with a normal load and wait until the drum reaches full speed.
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Step 2: Place your phone flat, screen up, on bare floor about 3 feet (1 m) from the washer. Rugs and carpet soften the reading, so use hard flooring if you can.
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Step 3: Tap Start (on iPhone, tap Allow). Then stand still or step out of the room. Your own footsteps show up as vibration too.
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Step 4: Let it run for the full 30 seconds.
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Step 5: Measure again where the shaking bothers you, like the middle of the next room or the room below an upstairs laundry. Floors usually move most in the middle, away from walls.
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Step 6: Save an image of each reading. Compare them after each fix, like pads, leveling or a lower spin speed.
What your result means
Your result lands on one of four levels. This page uses the people and buildings scale, which is based on peak velocity in millimeters per second (mm/s).
| Level | Range (peak velocity) | What to do |
|---|---|---|
| Barely noticeable | Under 0.25 mm/s under 0.010 in/s | Most people won't feel this. Very little of your washer's shake reaches this spot. |
| Noticeable | 0.25 to 1.0 mm/s 0.010 to 0.039 in/s | You may feel a light hum when you're sitting or lying still. This is common for a laundry on a wood-framed upper floor. |
| Strong | 1.0 to 2.5 mm/s 0.039 to 0.098 in/s | Clearly felt, and things on shelves may buzz or rattle. Worth trying the fixes below and testing again. |
| Very strong | 2.5 mm/s or more 0.098 in/s or more | Hard to ignore. Check the washer itself first: balance, feet and shipping bolts. If the floor also feels springy or sags, ask a contractor or structural engineer to look at it. |
Why washing machine floor vibration happens
Washing machine floor vibration depends as much on the floor as on the washer. The same machine can feel calm on a concrete slab and rattle a whole room on a wood-framed upper floor. The washer pushes on the floor through its four feet, and a springy floor passes that push along.
Floors have a natural bounce, like a diving board. AISC Design Guide 11, a standard reference on floor vibration, treats floors with a natural frequency below about 9 Hz as “low-frequency floors” that need checking for walking vibration. Very bouncy floors are often in the 4 to 8 Hz range. A washer drum passes through those speeds each time it speeds up and slows down, which is often when the shaking feels worst.
At full spin, a front-loader often turns at about 17 to 23 Hz (1,000 to 1,400 RPM). That’s usually faster than the floor’s bounce, so the floor responds less.
Is the shaking bad for your house?
Feeling a shake isn’t the same as damaging a building. Caltrans guidance lists continuous vibration damage guidelines of 0.3 in/s (about 7.6 mm/s) for older homes and 0.5 in/s (about 12.7 mm/s) for new homes. The top label on this page, Very strong, starts at 2.5 mm/s. So even a reading that’s hard to ignore is usually well below those guidelines.
Watch for signs that don’t need a phone: a sagging floor, cracked tile or grout near the washer, or doors that start to stick. Those are worth a professional look, whatever the reading. The construction vibration limits page shows the full tables from Caltrans and other sources. The original is in the Caltrans vibration guidance manual.
Common causes and fixes
The washer itself
An unbalanced load or a washer that rocks on one foot shakes the floor far more than a balanced, level one. Run the washing machine test first. Level the washer, lock the feet, and spread each load evenly.
Anti-vibration pads or a mat
Rubber pads under the feet stop walking and can soften what reaches the floor. They work best on a washer that’s already level. Test before and after in the same spot.
A lower spin speed
A slower spin puts less force into the floor. Dropping from, say, 1,400 to 1,000 RPM often helps. Your clothes will come out a little wetter.
Where the washer sits
Floors move least near load-bearing walls and over beams. If you’re moving the laundry or remodeling, put the washer there instead of in the middle of a room.
Stiffening the floor
Blocking between joists, adding joists alongside the old ones, or a post under a beam can make a floor much less bouncy. This is structural work. Ask a contractor, or a structural engineer if the floor sags.
Renters and neighbors
If you rent or share a building, save an image of each reading with the date. For shaking that comes and goes over hours, the house vibration logger keeps a record while you do other things.
What this tool can’t measure
- Sound. The thumps and hum you hear travel through the air as well as the floor. The phone only measures the shaking.
- Floor strength. It can’t tell whether joists are damaged, undersized or rotting.
- Very slow sway. Movement below about 1 Hz is too slow to read well.
- Certified numbers. Phone sensors vary, and a rug under the phone lowers the reading. Use the result as a good guide, not a certified measurement.
Frequently asked questions
Why does my washing machine shake the floor so much?
The washer's shake travels through its feet into the floor. Wood-framed floors flex, especially upstairs and in the middle of a long span, so they pass the shake along to the whole room. An unbalanced load or a washer that isn't level makes it much worse.
Is washing machine vibration upstairs normal?
Some is. A washer on an upper wood floor almost always shakes the floor more than one on a concrete slab. A reading of Noticeable is common, but Strong or Very strong means it's worth fixing the washer and looking at the floor.
Can a washing machine damage my floor?
The shaking from a washer is usually far below the levels linked to building damage in Caltrans guidance. Damage is more often from a leak or from years of a heavy machine on a weak spot. Sagging, cracked tile or a soft spot near the washer are worth getting checked.
Do anti-vibration pads work on a wood floor?
They often help, because they stop the washer from walking and soften what passes into the floor. Results vary with the pad and the floor. Measure in the same spot before and after so you know whether they made a difference.
Why does the floor shake most at the start and end of the spin?
Every floor has a natural bounce speed. As the drum speeds up and slows down, it passes through that speed for a few seconds and the floor responds strongly. At full spin, the drum usually turns faster than the floor's bounce, so it settles down.
Should I measure on the washer or on the floor?
Both, if you can. The washing machine vibration test measures the washer itself, and this page measures what reaches the floor. A calm washer with a shaking floor points to the floor; a rough washer points to the machine.
Last updated .